first commit

.gitignore

@@ -0,0 +1,9 @@
+# docker image build
+.dockerignore
+
+# user defined files
+.env
+docker-compose.override.yml
+mongo_data/
+redis_data/
+sharelatex_data/

CONTRIBUTING.md

@@ -0,0 +1,43 @@
+Contributing to Overleaf
+==========================
+
+Thank you for reading this! If you'd like to report a bug or join in the development
+of Overleaf, then here are some notes on how to do that.
+
+Reporting bugs and opening issues
+---------------------------------
+
+If you'd like to report a bug or open an issue, please **[check if there is an existing issue](https://github.com/overleaf/overleaf/issues).**
+If there is then please add any more information that you have, or give it a 👍.
+
+When submitting an issue please describe the issue as clearly as possible, including how to
+reproduce the bug, which situations it appears in, what you expected to happen, and what actually happens.
+If you can include a screenshot for front end issues that is very helpful.
+
+**Note**: If you are using [www.overleaf.com](www.overleaf.com) and have a problem, or if you would like to request a new feature, please contact the Support team at support@overleaf.com. Raise an issue here only to report bugs in the Community Edition release of Overleaf.
+
+Pull Requests
+-------------
+
+See [our wiki](https://github.com/overleaf/overleaf/wiki)
+for how to manage the Overleaf development environment and for our developer guidelines.
+
+We love pull requests, so be bold with them! Don't be afraid of going ahead
+and changing something, or adding a new feature. We're very happy to work with you
+to get your changes merged into Overleaf.
+
+If you're looking for something to work on, have a look at the [open issues](https://github.com/overleaf/overleaf/issues).
+
+Security
+--------
+
+Please see [our security policy](https://github.com/overleaf/overleaf/security/policy) if you would like to report a potential security vulnerability.
+
+Contributor License Agreement
+-----------------------------
+
+Before we can accept any contributions of code, we need you to agree to our
+[Contributor License Agreement](https://docs.google.com/forms/d/e/1FAIpQLSef79XH3mb7yIiMzZw-yALEegS-wyFetvjTiNBfZvf_IHD2KA/viewform?usp=sf_link).
+This is to ensure that you own the copyright of your contribution, and that you
+agree to give us a license to use it in both the open source version, and the version
+of Overleaf running at www.overleaf.com, which may have additional changes.

LICENSE

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
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+
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+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the work with which it is combined will remain governed by version
+3 of the GNU General Public License.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU Affero General Public License from time to time.  Such new versions
+will be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU Affero General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU Affero General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU Affero General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.

README.md

@@ -0,0 +1,76 @@
+<h1 align="center">
+  <br>
+  <a href="https://www.overleaf.com"><img src="doc/logo.png" alt="Overleaf" width="300"></a>
+</h1>
+
+<h4 align="center">An open-source online real-time collaborative LaTeX editor.</h4>
+
+<p align="center">
+  <a href="https://github.com/overleaf/overleaf/wiki">Wiki</a> •
+  <a href="https://www.overleaf.com/for/enterprises">Server Pro</a> •
+  <a href="#contributing">Contributing</a> •
+  <a href="https://mailchi.mp/overleaf.com/community-edition-and-server-pro">Mailing List</a> •
+  <a href="#authors">Authors</a> •
+  <a href="#license">License</a>
+</p>
+
+<img src="doc/screenshot.png" alt="A screenshot of a project being edited in Overleaf Community Edition">
+<p align="center">
+  Figure 1: A screenshot of a project being edited in Overleaf Community Edition.
+</p>
+
+## Community Edition
+
+[Overleaf](https://www.overleaf.com) is an open-source online real-time collaborative LaTeX editor. We run a hosted version at [www.overleaf.com](https://www.overleaf.com), but you can also run your own local version, and contribute to the development of Overleaf.
+
+## Enterprise
+
+If you want help installing and maintaining Overleaf in your lab or workplace, we offer an officially supported version called [Overleaf Server Pro](https://www.overleaf.com/for/enterprises). It also includes more features for security (SSO with LDAP or SAML), administration and collaboration (e.g. tracked changes). [Find out more!](https://www.overleaf.com/for/enterprises)
+
+## Keeping up to date
+
+Sign up to the [mailing list](https://mailchi.mp/overleaf.com/community-edition-and-server-pro) to get updates on Overleaf releases and development.
+
+## Installation
+
+We have detailed installation instructions in the [Overleaf Toolkit](https://github.com/overleaf/toolkit/).
+
+## Upgrading
+
+If you are upgrading from a previous version of Overleaf, please see the [Release Notes section on the Wiki](https://github.com/overleaf/overleaf/wiki#release-notes) for all of the versions between your current version and the version you are upgrading to.
+
+## Overleaf Docker Image
+
+This repo contains two dockerfiles, [`Dockerfile-base`](server-ce/Dockerfile-base), which builds the
+`sharelatex/sharelatex-base` image, and [`Dockerfile`](server-ce/Dockerfile) which builds the
+`sharelatex/sharelatex` (or "community") image.
+
+The Base image generally contains the basic dependencies like `wget`, plus `texlive`.
+We split this out because it's a pretty heavy set of
+dependencies, and it's nice to not have to rebuild all of that every time.
+
+The `sharelatex/sharelatex` image extends the base image and adds the actual Overleaf code
+and services.
+
+Use `make build-base` and `make build-community` from `server-ce/` to build these images.
+
+We use the [Phusion base-image](https://github.com/phusion/baseimage-docker)
+(which is extended by our `base` image) to provide us with a VM-like container
+in which to run the Overleaf services. Baseimage uses the `runit` service
+manager to manage services, and we add our init-scripts from the `server-ce/runit`
+folder.
+
+
+## Contributing
+
+Please see the [CONTRIBUTING](CONTRIBUTING.md) file for information on contributing to the development of Overleaf.
+
+## Authors
+
+[The Overleaf Team](https://www.overleaf.com/about)
+
+## License
+
+The code in this repository is released under the GNU AFFERO GENERAL PUBLIC LICENSE, version 3. A copy can be found in the [`LICENSE`](LICENSE) file.
+
+Copyright (c) Overleaf, 2014-2025.

bin/shared/mongodb-init-replica-set.js

@@ -0,0 +1,3 @@
+/* eslint-disable no-undef */
+
+rs.initiate({ _id: 'overleaf', members: [{ _id: 0, host: 'mongo:27017' }] })

develop/.gitignore

@@ -0,0 +1,3 @@
+/compiles/*
+!.gitkeep
+.env

develop/README.md

@@ -0,0 +1,89 @@
+# Overleaf Community Edition, development environment
+
+## Building and running
+
+In this `develop` directory, build the services:
+
+```shell
+bin/build
+```
+
+> [!NOTE]
+> If Docker is running out of RAM while building the services in parallel, create a `.env` file in this directory containing `COMPOSE_PARALLEL_LIMIT=1`.
+
+Then start the services:
+
+```shell
+bin/up
+```
+
+Once the services are running, open <http://localhost/launchpad> to create the first admin account.
+
+## TeX Live
+
+Compiling a PDF requires building a TeX Live image to handle the compilation inside Docker:
+
+```shell
+docker build texlive -t texlive-full
+```
+
+> [!NOTE]
+> To compile on a macOS host, you may need to override the path to the Docker socket by creating a `.env` file in this directory, containing
+> `DOCKER_SOCKET_PATH=/var/run/docker.sock.raw`
+
+## Development
+
+To avoid running `bin/build && bin/up` after every code change, you can run Overleaf
+Community Edition in _development mode_, where services will automatically update on code changes.
+
+To do this, use the included `bin/dev` script:
+
+```shell
+bin/dev
+```
+
+This will start all services using `nodemon`, which will automatically monitor the code and restart the services as necessary.
+
+To improve performance, you can start only a subset of the services in development mode by providing a space-separated list to the `bin/dev` script:
+
+```shell
+bin/dev [service1] [service2] ... [serviceN]
+```
+
+> [!NOTE]
+> Starting the `web` service in _development mode_ will only update the `web`
+> service when backend code changes. In order to automatically update frontend
+> code as well, make sure to start the `webpack` service in _development mode_
+> as well.
+
+If no services are named, all services will start in development mode.
+
+## Debugging
+
+When run in _development mode_ most services expose a debugging port to which
+you can attach a debugger such as
+[the inspector in Chrome's Dev Tools](chrome://inspect/) or one integrated into
+an IDE. The following table shows the port exposed on the **host machine** for
+each service:
+
+| Service            | Port |
+| ------------------ | ---- |
+| `web`              | 9229 |
+| `clsi`             | 9230 |
+| `chat`             | 9231 |
+| `contacts`         | 9232 |
+| `docstore`         | 9233 |
+| `document-updater` | 9234 |
+| `filestore`        | 9235 |
+| `notifications`    | 9236 |
+| `real-time`        | 9237 |
+| `history-v1`       | 9239 |
+| `project-history`  | 9240 |
+
+To attach to a service using Chrome's _remote debugging_, go to
+<chrome://inspect/> and make sure _Discover network targets_ is checked. Next
+click _Configure..._ and add an entry `localhost:[service port]` for each of the
+services you want to attach a debugger to.
+
+After adding an entry, the service will show up as a _Remote Target_ that you
+can inspect and debug.

develop/bin/build

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+docker compose build --pull "$@"

develop/bin/dev

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+docker-compose -f docker-compose.yml -f docker-compose.dev.yml up --no-deps --detach "$@"

develop/bin/down

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+docker compose down "$@"

develop/bin/logs

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+docker compose logs --follow --tail 10 --no-color "$@" \
+  | ggrep --line-buffered --invert-match "global.gc" \
+  | ggrep --line-buffered --invert-match "health.check" \
+  | ggrep --line-buffered --invert-match "slow event loop" \
+  | ggrep --line-buffered --invert-match "process.memoryUsage" \
+  | ggrep --line-buffered --only-matching "[{].*" \
+  | bunyan --output short

develop/bin/shell

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+docker compose exec -it "$@" /bin/bash

develop/bin/up

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+docker compose up --detach "$@"

develop/dev.env

@@ -0,0 +1,20 @@
+CHAT_HOST=chat
+CLSI_HOST=clsi
+CONTACTS_HOST=contacts
+DOCSTORE_HOST=docstore
+DOCUMENT_UPDATER_HOST=document-updater
+FILESTORE_HOST=filestore
+GRACEFUL_SHUTDOWN_DELAY_SECONDS=0
+HISTORY_V1_HOST=history-v1
+LISTEN_ADDRESS=0.0.0.0
+MONGO_HOST=mongo
+MONGO_URL=mongodb://mongo/sharelatex?directConnection=true
+NOTIFICATIONS_HOST=notifications
+PROJECT_HISTORY_HOST=project-history
+REALTIME_HOST=real-time
+REDIS_HOST=redis
+SESSION_SECRET=foo
+WEBPACK_HOST=webpack
+WEB_API_PASSWORD=overleaf
+WEB_API_USER=overleaf
+WEB_HOST=web

develop/docker-compose.dev.yml

@@ -0,0 +1,139 @@
+services:
+  clsi:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9230:9229"
+    volumes:
+      - ../services/clsi/app:/overleaf/services/clsi/app
+      - ../services/clsi/app.js:/overleaf/services/clsi/app.js
+      - ../services/clsi/config:/overleaf/services/clsi/config
+
+  chat:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9231:9229"
+    volumes:
+      - ../services/chat/app:/overleaf/services/chat/app
+      - ../services/chat/app.js:/overleaf/services/chat/app.js
+      - ../services/chat/config:/overleaf/services/chat/config
+
+  contacts:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9232:9229"
+    volumes:
+      - ../services/contacts/app:/overleaf/services/contacts/app
+      - ../services/contacts/app.js:/overleaf/services/contacts/app.js
+      - ../services/contacts/config:/overleaf/services/contacts/config
+
+  docstore:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9233:9229"
+    volumes:
+      - ../services/docstore/app:/overleaf/services/docstore/app
+      - ../services/docstore/app.js:/overleaf/services/docstore/app.js
+      - ../services/docstore/config:/overleaf/services/docstore/config
+
+  document-updater:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9234:9229"
+    volumes:
+      - ../services/document-updater/app:/overleaf/services/document-updater/app
+      - ../services/document-updater/app.js:/overleaf/services/document-updater/app.js
+      - ../services/document-updater/config:/overleaf/services/document-updater/config
+
+  filestore:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9235:9229"
+    volumes:
+      - ../services/filestore/app:/overleaf/services/filestore/app
+      - ../services/filestore/app.js:/overleaf/services/filestore/app.js
+      - ../services/filestore/config:/overleaf/services/filestore/config
+
+  history-v1:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9239:9229"
+    volumes:
+      - ../services/history-v1/api:/overleaf/services/history-v1/api
+      - ../services/history-v1/app.js:/overleaf/services/history-v1/app.js
+      - ../services/history-v1/config:/overleaf/services/history-v1/config
+      - ../services/history-v1/storage:/overleaf/services/history-v1/storage
+      - ../services/history-v1/knexfile.js:/overleaf/services/history-v1/knexfile.js
+      - ../services/history-v1/migrations:/overleaf/services/history-v1/migrations
+
+  notifications:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9236:9229"
+    volumes:
+      - ../services/notifications/app:/overleaf/services/notifications/app
+      - ../services/notifications/app.js:/overleaf/services/notifications/app.js
+      - ../services/notifications/config:/overleaf/services/notifications/config
+
+  project-history:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9240:9229"
+    volumes:
+      - ../services/project-history/app:/overleaf/services/project-history/app
+      - ../services/project-history/app.js:/overleaf/services/project-history/app.js
+      - ../services/project-history/config:/overleaf/services/project-history/config
+
+  real-time:
+    command: ["node", "--watch", "app.js"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9237:9229"
+    volumes:
+      - ../services/real-time/app:/overleaf/services/real-time/app
+      - ../services/real-time/app.js:/overleaf/services/real-time/app.js
+      - ../services/real-time/config:/overleaf/services/real-time/config
+
+  web:
+    command: ["node", "--watch", "app.js", "--watch-locales"]
+    environment:
+      - NODE_OPTIONS=--inspect=0.0.0.0:9229
+    ports:
+      - "127.0.0.1:9229:9229"
+    volumes:
+      - ../services/web/app:/overleaf/services/web/app
+      - ../services/web/app.mjs:/overleaf/services/web/app.mjs
+      - ../services/web/config:/overleaf/services/web/config
+      - ../services/web/locales:/overleaf/services/web/locales
+      - ../services/web/modules:/overleaf/services/web/modules
+      - ../services/web/public:/overleaf/services/web/public
+
+  webpack:
+    volumes:
+      - ../services/web/app:/overleaf/services/web/app
+      - ../services/web/config:/overleaf/services/web/config
+      - ../services/web/frontend:/overleaf/services/web/frontend
+      - ../services/web/locales:/overleaf/services/web/locales
+      - ../services/web/modules:/overleaf/services/web/modules
+      - ../services/web/public:/overleaf/services/web/public
+      - ../services/web/transform:/overleaf/services/web/transform
+      - ../services/web/types:/overleaf/services/web/types
+      - ../services/web/webpack-plugins:/overleaf/services/web/webpack-plugins

develop/docker-compose.yml

@@ -0,0 +1,175 @@
+volumes:
+  clsi-cache:
+  clsi-output:
+  filestore-public-files:
+  filestore-template-files:
+  filestore-uploads:
+  filestore-user-files:
+  mongo-data:
+  redis-data:
+  sharelatex-data:
+  web-data:
+  history-v1-buckets:
+
+services:
+  chat:
+    build:
+      context: ..
+      dockerfile: services/chat/Dockerfile
+    env_file:
+      - dev.env
+
+  clsi:
+    build:
+      context: ..
+      dockerfile: services/clsi/Dockerfile
+    env_file:
+      - dev.env
+    environment:
+      - DOCKER_RUNNER=true
+      - TEXLIVE_IMAGE=texlive-full # docker build texlive -t texlive-full
+      - COMPILES_HOST_DIR=${PWD}/compiles
+      - OUTPUT_HOST_DIR=${PWD}/output
+    user: root
+    volumes:
+      - ${PWD}/compiles:/overleaf/services/clsi/compiles
+      - ${DOCKER_SOCKET_PATH:-/var/run/docker.sock}:/var/run/docker.sock
+      - clsi-cache:/overleaf/services/clsi/cache
+      - clsi-output:/overleaf/services/clsi/output
+
+  contacts:
+    build:
+      context: ..
+      dockerfile: services/contacts/Dockerfile
+    env_file:
+      - dev.env
+
+  docstore:
+    build:
+      context: ..
+      dockerfile: services/docstore/Dockerfile
+    env_file:
+      - dev.env
+
+  document-updater:
+    build:
+      context: ..
+      dockerfile: services/document-updater/Dockerfile
+    env_file:
+      - dev.env
+
+  filestore:
+    build:
+      context: ..
+      dockerfile: services/filestore/Dockerfile
+    env_file:
+      - dev.env
+#    environment:
+#      - ENABLE_CONVERSIONS=true
+    volumes:
+      - filestore-public-files:/overleaf/services/filestore/public_files
+      - filestore-template-files:/overleaf/services/filestore/template_files
+      - filestore-uploads:/overleaf/services/filestore/uploads
+      - filestore-user-files:/overleaf/services/filestore/user_files
+
+  history-v1:
+    build:
+      context: ..
+      dockerfile: services/history-v1/Dockerfile
+    env_file:
+        - dev.env
+    environment:
+      OVERLEAF_EDITOR_ANALYTICS_BUCKET: "/buckets/analytics"
+      OVERLEAF_EDITOR_BLOBS_BUCKET: "/buckets/blobs"
+      OVERLEAF_EDITOR_CHUNKS_BUCKET: "/buckets/chunks"
+      OVERLEAF_EDITOR_PROJECT_BLOBS_BUCKET: "/buckets/project_blobs"
+      OVERLEAF_EDITOR_ZIPS_BUCKET: "/buckets/zips"
+      PERSISTOR_BACKEND: fs
+    volumes:
+        - history-v1-buckets:/buckets
+
+  mongo:
+    image: mongo:6.0
+    command: --replSet overleaf
+    ports:
+      - "127.0.0.1:27017:27017" # for debugging
+    volumes:
+      - mongo-data:/data/db
+      - ../bin/shared/mongodb-init-replica-set.js:/docker-entrypoint-initdb.d/mongodb-init-replica-set.js
+    environment:
+      MONGO_INITDB_DATABASE: sharelatex
+    extra_hosts:
+      # Required when using the automatic database setup for initializing the
+      # replica set. This override is not needed when running the setup after
+      # starting up mongo.
+      - mongo:127.0.0.1
+
+  notifications:
+    build:
+      context: ..
+      dockerfile: services/notifications/Dockerfile
+    env_file:
+      - dev.env
+
+  project-history:
+    build:
+      context: ..
+      dockerfile: services/project-history/Dockerfile
+    env_file:
+        - dev.env
+
+  real-time:
+    build:
+      context: ..
+      dockerfile: services/real-time/Dockerfile
+    env_file:
+      - dev.env
+
+  redis:
+    image: redis:5
+    ports:
+      - "127.0.0.1:6379:6379" # for debugging
+    volumes:
+      - redis-data:/data
+
+  web:
+    build:
+      context: ..
+      dockerfile: services/web/Dockerfile
+      target: dev
+    env_file:
+      - dev.env
+    environment:
+      - APP_NAME=Overleaf Community Edition
+      - ENABLED_LINKED_FILE_TYPES=project_file,project_output_file
+      - EMAIL_CONFIRMATION_DISABLED=true
+      - NODE_ENV=development
+      - OVERLEAF_ALLOW_PUBLIC_ACCESS=true
+    command: ["node", "app.mjs"]
+    volumes:
+      - sharelatex-data:/var/lib/overleaf
+      - web-data:/overleaf/services/web/data
+    depends_on:
+      - mongo
+      - redis
+      - chat
+      - clsi
+      - contacts
+      - docstore
+      - document-updater
+      - filestore
+      - history-v1
+      - notifications
+      - project-history
+      - real-time
+
+  webpack:
+    build:
+      context: ..
+      dockerfile: services/web/Dockerfile
+      target: webpack
+    command: ["npx", "webpack", "serve", "--config", "webpack.config.dev-env.js"]
+    ports:
+      - "127.0.0.1:80:3808"
+    volumes:
+      - ./webpack.config.dev-env.js:/overleaf/services/web/webpack.config.dev-env.js

develop/texlive/Dockerfile

@@ -0,0 +1,8 @@
+FROM debian:testing-slim
+
+RUN apt-get update
+RUN apt-cache depends texlive-full | grep "Depends: " | grep -v -- "-doc" | grep -v -- "-lang-" | sed 's/Depends: //' | xargs apt-get install -y --no-install-recommends
+RUN apt-get install -y --no-install-recommends fontconfig inkscape pandoc python3-pygments
+
+RUN useradd tex
+USER tex

develop/webpack.config.dev-env.js

@@ -0,0 +1,23 @@
+const { merge } = require('webpack-merge')
+
+const base = require('./webpack.config.dev')
+
+module.exports = merge(base, {
+  devServer: {
+    allowedHosts: 'auto',
+    devMiddleware: {
+      index: false,
+    },
+    proxy: [
+      {
+        context: '/socket.io/**',
+        target: 'http://real-time:3026',
+        ws: true,
+      },
+      {
+        context: ['!**/*.js', '!**/*.css', '!**/*.json'],
+        target: 'http://web:3000',
+      },
+    ],
+  },
+})

docker-compose.debug.yml

@@ -0,0 +1,23 @@
+version: '2.2'
+services:
+    sharelatex:
+        ports:
+            - 30000:30000
+            - 30150:30150
+            - 30120:30120
+            - 30050:30050
+            - 30420:30420
+            - 30030:30030
+            - 30160:30160
+            - 30360:30360
+            - 30130:30130
+            - 30100:30100
+            - 30540:30540
+            - 30640:30640
+            - 40000:40000
+
+            # Server Pro
+            - 30070:30070
+            - 30400:30400
+        environment:
+            DEBUG_NODE: 'true'

docker-compose.yml

@@ -0,0 +1,146 @@
+services:
+    sharelatex:
+        restart: always
+        # Server Pro users:
+        # image: quay.io/sharelatex/sharelatex-pro
+        image: sharelatex/sharelatex:arm64
+        container_name: sharelatex
+        depends_on:
+            mongo:
+                condition: service_healthy
+            redis:
+                condition: service_started
+        ports:
+            - 80:80
+        stop_grace_period: 60s
+        volumes:
+            - ~/overleaf/sharelatex_data:/var/lib/overleaf
+            # - /opt/homebrew/Cellar/texlive:/usr/local/texlive
+            ########################################################################
+            ####  Server Pro: Uncomment the following line to mount the docker  ####
+            ####             socket, required for Sibling Containers to work    ####
+            ########################################################################
+            # - /var/run/docker.sock:/var/run/docker.sock
+        environment:
+
+            OVERLEAF_APP_NAME: Overleaf Community Edition
+
+            OVERLEAF_MONGO_URL: mongodb://mongo/sharelatex
+
+            # Same property, unfortunately with different names in
+            # different locations
+            OVERLEAF_REDIS_HOST: redis
+            REDIS_HOST: redis
+
+            ENABLED_LINKED_FILE_TYPES: 'project_file,project_output_file'
+
+            # Enables Thumbnail generation using ImageMagick
+            ENABLE_CONVERSIONS: 'true'
+
+            # Disables email confirmation requirement
+            EMAIL_CONFIRMATION_DISABLED: 'true'
+
+            ## Set for SSL via nginx-proxy
+            #VIRTUAL_HOST: 103.112.212.22
+
+            # OVERLEAF_SITE_URL: http://overleaf.example.com
+            # OVERLEAF_NAV_TITLE: Overleaf Community Edition
+            # OVERLEAF_HEADER_IMAGE_URL: http://example.com/mylogo.png
+            # OVERLEAF_ADMIN_EMAIL: support@it.com
+
+            # OVERLEAF_LEFT_FOOTER: '[{"text": "Another page I want to link to can be found <a href=\"here\">here</a>"} ]'
+            # OVERLEAF_RIGHT_FOOTER: '[{"text": "Hello I am on the Right"} ]'
+
+            # OVERLEAF_EMAIL_FROM_ADDRESS: "hello@example.com"
+
+            # OVERLEAF_EMAIL_AWS_SES_ACCESS_KEY_ID:
+            # OVERLEAF_EMAIL_AWS_SES_SECRET_KEY:
+
+            # OVERLEAF_EMAIL_SMTP_HOST: smtp.example.com
+            # OVERLEAF_EMAIL_SMTP_PORT: 587
+            # OVERLEAF_EMAIL_SMTP_SECURE: false
+            # OVERLEAF_EMAIL_SMTP_USER:
+            # OVERLEAF_EMAIL_SMTP_PASS:
+            # OVERLEAF_EMAIL_SMTP_TLS_REJECT_UNAUTH: true
+            # OVERLEAF_EMAIL_SMTP_IGNORE_TLS: false
+            # OVERLEAF_EMAIL_SMTP_NAME: '127.0.0.1'
+            # OVERLEAF_EMAIL_SMTP_LOGGER: true
+            # OVERLEAF_CUSTOM_EMAIL_FOOTER: "This system is run by department x"
+
+            # ENABLE_CRON_RESOURCE_DELETION: true
+
+            ################
+            ## Server Pro ##
+            ################
+
+            ## Sandboxed Compiles: https://github.com/overleaf/overleaf/wiki/Server-Pro:-Sandboxed-Compiles
+            # SANDBOXED_COMPILES: 'true'
+            # SANDBOXED_COMPILES_SIBLING_CONTAINERS: 'true'
+            ### Bind-mount source for /var/lib/overleaf/data/compiles inside the container.
+            # SANDBOXED_COMPILES_HOST_DIR_COMPILES: '/home/user/sharelatex_data/data/compiles'
+            ### Bind-mount source for /var/lib/overleaf/data/output inside the container.
+            # SANDBOXED_COMPILES_HOST_DIR_OUTPUT: '/home/user/sharelatex_data/data/output'
+
+            ## Works with test LDAP server shown at bottom of docker compose
+            # OVERLEAF_LDAP_URL: 'ldap://ldap:389'
+            # OVERLEAF_LDAP_SEARCH_BASE: 'ou=people,dc=planetexpress,dc=com'
+            # OVERLEAF_LDAP_SEARCH_FILTER: '(uid={{username}})'
+            # OVERLEAF_LDAP_BIND_DN: 'cn=admin,dc=planetexpress,dc=com'
+            # OVERLEAF_LDAP_BIND_CREDENTIALS: 'GoodNewsEveryone'
+            # OVERLEAF_LDAP_EMAIL_ATT: 'mail'
+            # OVERLEAF_LDAP_NAME_ATT: 'cn'
+            # OVERLEAF_LDAP_LAST_NAME_ATT: 'sn'
+            # OVERLEAF_LDAP_UPDATE_USER_DETAILS_ON_LOGIN: 'true'
+
+            # OVERLEAF_TEMPLATES_USER_ID: "578773160210479700917ee5"
+            # OVERLEAF_NEW_PROJECT_TEMPLATE_LINKS: '[ {"name":"All Templates","url":"/templates/all"}]'
+
+
+            # OVERLEAF_PROXY_LEARN: "true"
+
+    mongo:
+        restart: always
+        image: mongo:6.0
+        container_name: mongo
+        command: '--replSet overleaf'
+        volumes:
+            - ~/overleaf/mongo_data:/data/db
+            - ./bin/shared/mongodb-init-replica-set.js:/docker-entrypoint-initdb.d/mongodb-init-replica-set.js
+        environment:
+          MONGO_INITDB_DATABASE: sharelatex
+        extra_hosts:
+          # Required when using the automatic database setup for initializing the replica set.
+          # This override is not needed when running the setup after starting up mongo.
+          - mongo:127.0.0.1
+        healthcheck:
+            test: echo 'db.stats().ok' | mongosh localhost:27017/test --quiet
+            interval: 10s
+            timeout: 10s
+            retries: 5
+
+    redis:
+        restart: always
+        image: redis:6.2
+        container_name: redis
+        volumes:
+            - ~/overleaf/redis_data:/data
+
+    # ldap:
+    #    restart: always
+    #    image: rroemhild/test-openldap
+    #    container_name: ldap
+
+    # See https://github.com/jwilder/nginx-proxy for documentation on how to configure the nginx-proxy container,
+    # and https://github.com/overleaf/overleaf/wiki/HTTPS-reverse-proxy-using-Nginx for an example of some recommended
+    # settings. We recommend using a properly managed nginx instance outside of the Overleaf Server Pro setup,
+    # but the example here can be used if you'd prefer to run everything with docker-compose
+
+    # nginx-proxy:
+    #     image: jwilder/nginx-proxy
+    #     container_name: nginx-proxy
+    #     ports:
+    #       - "80:80"
+    #       - "443:443"
+    #     volumes:
+    #       - /var/run/docker.sock:/tmp/docker.sock:ro
+    #       - /home/overleaf/tmp:/etc/nginx/certs

libraries/access-token-encryptor/.gitignore

@@ -0,0 +1,46 @@
+compileFolder
+
+Compiled source #
+###################
+*.com
+*.class
+*.dll
+*.exe
+*.o
+*.so
+
+# Packages #
+############
+# it's better to unpack these files and commit the raw source
+# git has its own built in compression methods
+*.7z
+*.dmg
+*.gz
+*.iso
+*.jar
+*.rar
+*.tar
+*.zip
+
+# Logs and databases #
+######################
+*.log
+*.sql
+*.sqlite
+
+# OS generated files #
+######################
+.DS_Store?
+ehthumbs.db
+Icon?
+Thumbs.db
+
+/node_modules/*
+data/*/*
+
+**.swp
+
+/log.json
+hash_folder
+
+.npmrc

libraries/access-token-encryptor/.mocharc.json

@@ -0,0 +1,6 @@
+{
+  "ui": "bdd",
+  "recursive": "true",
+  "reporter": "spec",
+  "require": "test/setup.js"
+}

libraries/access-token-encryptor/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/access-token-encryptor/LICENSE

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  Developers that use our General Public Licenses protect your rights
+with two steps: (1) assert copyright on the software, and (2) offer
+you this License which gives you legal permission to copy, distribute
+and/or modify the software.
+
+  A secondary benefit of defending all users' freedom is that
+improvements made in alternate versions of the program, if they
+receive widespread use, become available for other developers to
+incorporate.  Many developers of free software are heartened and
+encouraged by the resulting cooperation.  However, in the case of
+software used on network servers, this result may fail to come about.
+The GNU General Public License permits making a modified version and
+letting the public access it on a server without ever releasing its
+source code to the public.
+
+  The GNU Affero General Public License is designed specifically to
+ensure that, in such cases, the modified source code becomes available
+to the community.  It requires the operator of a network server to
+provide the source code of the modified version running there to the
+users of that server.  Therefore, public use of a modified version, on
+a publicly accessible server, gives the public access to the source
+code of the modified version.
+
+  An older license, called the Affero General Public License and
+published by Affero, was designed to accomplish similar goals.  This is
+a different license, not a version of the Affero GPL, but Affero has
+released a new version of the Affero GPL which permits relicensing under
+this license.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU Affero General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
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+"recipients" may be individuals or organizations.
+
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+  A "covered work" means either the unmodified Program or a work based
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+  You may convey verbatim copies of the Program's source code as you
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+keep intact all notices of the absence of any warranty; and give all
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libraries/access-token-encryptor/README.md

@@ -0,0 +1,3 @@
+# Access Token Encryptor
+
+Used in third-party-references, to encrypt access tokens

libraries/access-token-encryptor/buildscript.txt

@@ -0,0 +1,10 @@
+access-token-encryptor
+--dependencies=None
+--docker-repos=gcr.io/overleaf-ops
+--env-add=
+--env-pass-through=
+--esmock-loader=False
+--is-library=True
+--node-version=20.18.2
+--public-repo=False
+--script-version=4.7.0

libraries/access-token-encryptor/index.js

@@ -0,0 +1 @@
+module.exports = require('./lib/js/AccessTokenEncryptor')

libraries/access-token-encryptor/lib/js/AccessTokenEncryptor.js

@@ -0,0 +1,164 @@
+const { promisify } = require('node:util')
+const crypto = require('node:crypto')
+
+const ALGORITHM = 'aes-256-ctr'
+
+const cryptoHkdf = promisify(crypto.hkdf)
+const cryptoRandomBytes = promisify(crypto.randomBytes)
+
+class AbstractAccessTokenScheme {
+  constructor(cipherLabel, cipherPassword) {
+    this.cipherLabel = cipherLabel
+    this.cipherPassword = cipherPassword
+  }
+
+  /**
+   * @param {Object} json
+   * @return {Promise<string>}
+   */
+  async encryptJson(json) {
+    throw new Error('encryptJson is not implemented')
+  }
+
+  /**
+   * @param {string} encryptedJson
+   * @return {Promise<Object>}
+   */
+  async decryptToJson(encryptedJson) {
+    throw new Error('decryptToJson is not implemented')
+  }
+}
+
+class AccessTokenSchemeWithGenericKeyFn extends AbstractAccessTokenScheme {
+  /**
+   * @param {Buffer} salt
+   * @return {Promise<Buffer>}
+   */
+  async keyFn(salt) {
+    throw new Error('keyFn is not implemented')
+  }
+
+  async encryptJson(json) {
+    const plainText = JSON.stringify(json)
+
+    const bytes = await cryptoRandomBytes(32)
+    const salt = bytes.slice(0, 16)
+    const iv = bytes.slice(16, 32)
+    const key = await this.keyFn(salt)
+
+    const cipher = crypto.createCipheriv(ALGORITHM, key, iv)
+    const cipherText =
+      cipher.update(plainText, 'utf8', 'base64') + cipher.final('base64')
+
+    return [
+      this.cipherLabel,
+      salt.toString('hex'),
+      cipherText,
+      iv.toString('hex'),
+    ].join(':')
+  }
+
+  async decryptToJson(encryptedJson) {
+    const [, salt, cipherText, iv] = encryptedJson.split(':', 4)
+    const key = await this.keyFn(Buffer.from(salt, 'hex'))
+
+    const decipher = crypto.createDecipheriv(
+      ALGORITHM,
+      key,
+      Buffer.from(iv, 'hex')
+    )
+    const plainText =
+      decipher.update(cipherText, 'base64', 'utf8') + decipher.final('utf8')
+    try {
+      return JSON.parse(plainText)
+    } catch (e) {
+      throw new Error('error decrypting token')
+    }
+  }
+}
+
+class AccessTokenSchemeV3 extends AccessTokenSchemeWithGenericKeyFn {
+  async keyFn(salt) {
+    const optionalInfo = ''
+    return await cryptoHkdf(
+      'sha512',
+      this.cipherPassword,
+      salt,
+      optionalInfo,
+      32
+    )
+  }
+}
+
+class AccessTokenEncryptor {
+  constructor(settings) {
+    /**
+     * @type {Map<string, AbstractAccessTokenScheme>}
+     */
+    this.schemeByCipherLabel = new Map()
+    for (const cipherLabel of Object.keys(settings.cipherPasswords)) {
+      if (!cipherLabel) {
+        throw new Error('cipherLabel cannot be empty')
+      }
+      if (cipherLabel.match(/:/)) {
+        throw new Error(
+          `cipherLabel must not contain a colon (:), got ${cipherLabel}`
+        )
+      }
+      const [, version] = cipherLabel.split('-')
+      if (!version) {
+        throw new Error(
+          `cipherLabel must contain version suffix (e.g. 2042.1-v42), got ${cipherLabel}`
+        )
+      }
+
+      const cipherPassword = settings.cipherPasswords[cipherLabel]
+      if (!cipherPassword) {
+        throw new Error(`cipherPasswords['${cipherLabel}'] is missing`)
+      }
+      if (cipherPassword.length < 16) {
+        throw new Error(`cipherPasswords['${cipherLabel}'] is too short`)
+      }
+
+      let scheme
+      switch (version) {
+        case 'v3':
+          scheme = new AccessTokenSchemeV3(cipherLabel, cipherPassword)
+          break
+        default:
+          throw new Error(`unknown version '${version}' for ${cipherLabel}`)
+      }
+      this.schemeByCipherLabel.set(cipherLabel, scheme)
+    }
+
+    /** @type {AbstractAccessTokenScheme} */
+    this.defaultScheme = this.schemeByCipherLabel.get(settings.cipherLabel)
+    if (!this.defaultScheme) {
+      throw new Error(`unknown default cipherLabel ${settings.cipherLabel}`)
+    }
+  }
+
+  promises = {
+    encryptJson: async json => await this.defaultScheme.encryptJson(json),
+    decryptToJson: async encryptedJson => {
+      const [label] = encryptedJson.split(':', 1)
+      const scheme = this.schemeByCipherLabel.get(label)
+      if (!scheme) {
+        throw new Error('unknown access-token-encryptor label ' + label)
+      }
+      return await scheme.decryptToJson(encryptedJson)
+    },
+  }
+
+  encryptJson(json, callback) {
+    this.promises.encryptJson(json).then(s => callback(null, s), callback)
+  }
+
+  decryptToJson(encryptedJson, callback) {
+    this.promises
+      .decryptToJson(encryptedJson)
+      .then(o => callback(null, o), callback)
+  }
+}
+
+module.exports = AccessTokenEncryptor

libraries/access-token-encryptor/package.json

@@ -0,0 +1,28 @@
+{
+  "name": "@overleaf/access-token-encryptor",
+  "version": "3.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "npm run lint && npm run format && npm run types:check && npm run test:unit",
+    "lint": "eslint --ext .js --ext .cjs --ext .ts --max-warnings 0 --format unix .",
+    "lint:fix": "eslint --fix --ext .js --ext .cjs --ext .ts .",
+    "format": "prettier --list-different $PWD/'**/*.{js,cjs,ts}'",
+    "format:fix": "prettier --write $PWD/'**/*.{js,cjs,ts}'",
+    "test:ci": "npm run test:unit",
+    "test:unit": "mocha --exit test/**/*.{js,cjs}",
+    "types:check": "tsc --noEmit"
+  },
+  "author": "",
+  "license": "AGPL-3.0-only",
+  "dependencies": {
+    "lodash": "^4.17.21"
+  },
+  "devDependencies": {
+    "chai": "^4.3.6",
+    "chai-as-promised": "^7.1.1",
+    "mocha": "^11.1.0",
+    "sandboxed-module": "^2.0.4",
+    "typescript": "^5.0.4"
+  }
+}

libraries/access-token-encryptor/scripts/helpers/format-usage-stats.js

@@ -0,0 +1,27 @@
+function formatTokenUsageStats(STATS) {
+  const prettyStats = []
+  const sortedStats = Object.entries(STATS).sort((a, b) =>
+    a[0] > b[0] ? 1 : -1
+  )
+  const totalByName = {}
+  for (const [key, n] of sortedStats) {
+    const [name, version, collectionName, path, label] = key.split(':')
+    totalByName[name] = (totalByName[name] || 0) + n
+    prettyStats.push({ name, version, collectionName, path, label, n })
+  }
+  for (const row of prettyStats) {
+    row.percentage = ((100 * row.n) / totalByName[row.name])
+      .toFixed(2)
+      .padStart(6)
+  }
+
+  if (prettyStats.length === 0) {
+    console.warn('---')
+    console.warn('Found 0 access tokens.')
+    console.warn('---')
+  } else {
+    console.table(prettyStats)
+  }
+}
+
+module.exports = { formatTokenUsageStats }

libraries/access-token-encryptor/scripts/helpers/re-encrypt-tokens.js

@@ -0,0 +1,108 @@
+const _ = require('lodash')
+const { formatTokenUsageStats } = require('./format-usage-stats')
+
+const LOG_EVERY_IN_S = parseInt(process.env.LOG_EVERY_IN_S || '5', 10)
+const DRY_RUN = !process.argv.includes('--dry-run=false')
+
+/**
+ * @param {AccessTokenEncryptor} accessTokenEncryptor
+ * @param {string} encryptedJson
+ * @return {Promise<string>}
+ */
+async function reEncryptTokens(accessTokenEncryptor, encryptedJson) {
+  return await new Promise((resolve, reject) => {
+    accessTokenEncryptor.decryptToJson(encryptedJson, (err, json) => {
+      if (err) return reject(err)
+      accessTokenEncryptor.encryptJson(json, (err, reEncryptedJson) => {
+        if (err) return reject(err)
+        resolve(reEncryptedJson)
+      })
+    })
+  })
+}
+
+/**
+ * @param {AccessTokenEncryptor} accessTokenEncryptor
+ * @param {Collection} collection
+ * @param {Object} paths
+ * @param {Object} queryOptions
+ * @return {Promise<{}>}
+ */
+async function reEncryptTokensInCollection({
+  accessTokenEncryptor,
+  collection,
+  paths,
+  queryOptions,
+}) {
+  const { collectionName } = collection
+  const stats = {}
+
+  let processed = 0
+  let updatedNUsers = 0
+  let lastLog = 0
+  const logProgress = () => {
+    if (DRY_RUN) {
+      console.warn(
+        `processed ${processed} | Would have updated ${updatedNUsers} users`
+      )
+    } else {
+      console.warn(`processed ${processed} | Updated ${updatedNUsers} users`)
+    }
+  }
+
+  const projection = { _id: 1 }
+  for (const path of Object.values(paths)) {
+    projection[path] = 1
+  }
+  const cursor = collection.find(
+    {},
+    {
+      ...queryOptions,
+      projection,
+    }
+  )
+
+  for await (const doc of cursor) {
+    processed++
+
+    let update = null
+    for (const [name, path] of Object.entries(paths)) {
+      const blob = _.get(doc, path)
+      if (!blob) continue
+      // Schema: LABEL-VERSION:SALT:CIPHERTEXT:IV
+      const [label] = blob.split(':')
+      let [, version] = label.split('-')
+      version = version || 'v2'
+
+      const key = [name, version, collectionName, path, label].join(':')
+      stats[key] = (stats[key] || 0) + 1
+
+      if (version === 'v2') {
+        update = update || {}
+        update[path] = await reEncryptTokens(accessTokenEncryptor, blob)
+      }
+    }
+
+    if (Date.now() - lastLog >= LOG_EVERY_IN_S * 1000) {
+      logProgress()
+      lastLog = Date.now()
+    }
+    if (update) {
+      updatedNUsers++
+
+      const { _id } = doc
+      if (DRY_RUN) {
+        console.log('Would upgrade tokens for user', _id, Object.keys(update))
+      } else {
+        console.log('Upgrading tokens for user', _id, Object.keys(update))
+        await collection.updateOne({ _id }, { $set: update })
+      }
+    }
+  }
+  logProgress()
+  formatTokenUsageStats(stats)
+}
+
+module.exports = {
+  reEncryptTokensInCollection,
+}

libraries/access-token-encryptor/test/setup.js

@@ -0,0 +1,13 @@
+const chai = require('chai')
+const chaiAsPromised = require('chai-as-promised')
+const SandboxedModule = require('sandboxed-module')
+
+chai.use(chaiAsPromised)
+
+SandboxedModule.configure({
+  sourceTransformers: {
+    removeNodePrefix: function (source) {
+      return source.replace(/require\(['"]node:/g, "require('")
+    },
+  },
+})

libraries/access-token-encryptor/test/unit/js/AccessTokenEncryptorTests.js

@@ -0,0 +1,305 @@
+const chai = require('chai')
+chai.should()
+const { expect } = chai
+const modulePath = '../../../index.js'
+const SandboxedModule = require('sandboxed-module')
+
+describe('AccessTokenEncryptor', function () {
+  beforeEach(function () {
+    this.testObject = { hello: 'world' }
+    this.encrypted2015 =
+      '2015.1:473a66fb5d816bc716f278ab819d88a5:+mTg7O9sgUND8pNQFG6h2GE='
+    this.encrypted2016 =
+      '2016.1:76a7d64a444ccee1a515b49c44844a69:m5YSkexUsLjcF4gLncm72+k='
+    this.encrypted2019 =
+      '2019.1:627143b2ab185a020c8720253a4c984e:7gnY6Ez3/Y3UWgLHLfBtJsE=:bf75cecb6aeea55b3c060e1122d2a82d'
+    this.encrypted2023 =
+      '2023.1-v3:a6dd3781dd6ce93a4134874b505a209c:9TdIDAc8V9SeR0ffSn63Jj4=:d8b2de0b733c81b949993dce229abb4c'
+    this.badLabel = 'xxxxxx:c7a39310056b694c:jQf+Uh5Den3JREtvc82GW5Q='
+    this.badKey = '2015.1:d7a39310056b694c:jQf+Uh5Den3JREtvc82GW5Q='
+    this.badCipherText = '2015.1:c7a39310056b694c:xQf+Uh5Den3JREtvc82GW5Q='
+    this.settings = {
+      cipherLabel: '2023.1-v3',
+      cipherPasswords: {
+        '2023.1-v3': '44444444444444444444444444444444444444',
+      },
+    }
+    this.AccessTokenEncryptor = SandboxedModule.require(modulePath, {
+      globals: {
+        Buffer,
+      },
+    })
+    this.encryptor = new this.AccessTokenEncryptor(this.settings)
+  })
+
+  describe('invalid settings', function () {
+    it('should flag missing label', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '',
+            cipherPasswords: { '': '' },
+          })
+      ).to.throw(/cipherLabel cannot be empty/)
+    })
+
+    it('should flag invalid label with colon', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023:1-v2',
+            cipherPasswords: { '2023:1-v2': '' },
+          })
+      ).to.throw(/colon/)
+    })
+
+    it('should flag missing password', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherPasswords: { '2023.1-v3': '' },
+            cipherVersions: { '2023.1-v3': 'v3' },
+          })
+      ).to.throw(/cipherPasswords.+ missing/)
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023.1-v3',
+            cipherPasswords: { '2023.1-v3': undefined },
+          })
+      ).to.throw(/cipherPasswords.+ missing/)
+    })
+
+    it('should flag short password', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023.1-v3',
+            cipherPasswords: { '2023.1-v3': 'foo' },
+          })
+      ).to.throw(/cipherPasswords.+ too short/)
+    })
+
+    it('should flag missing version', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023.1',
+            cipherPasswords: { 2023.1: '11111111111111111111111111111111' },
+          })
+      ).to.throw(/must contain version suffix/)
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023.1-',
+            cipherPasswords: { '2023.1-': '11111111111111111111111111111111' },
+          })
+      ).to.throw(/must contain version suffix/)
+    })
+
+    it('should flag invalid version', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2023.1-v0',
+            cipherPasswords: {
+              '2023.1-v0': '11111111111111111111111111111111',
+            },
+          })
+      ).to.throw(/unknown version/)
+    })
+
+    it('should flag unknown default scheme', function () {
+      expect(
+        () =>
+          new this.AccessTokenEncryptor({
+            cipherLabel: '2000.1-v3',
+            cipherPasswords: {
+              '2023.1-v3': '11111111111111111111111111111111',
+            },
+          })
+      ).to.throw(/unknown default cipherLabel/)
+    })
+  })
+
+  describe('sync', function () {
+    describe('encrypt', function () {
+      it('should encrypt the object', function (done) {
+        this.encryptor.encryptJson(this.testObject, (err, encrypted) => {
+          expect(err).to.be.null
+          encrypted.should.match(
+            /^2023.1-v3:[0-9a-f]{32}:[a-zA-Z0-9=+/]+:[0-9a-f]{32}$/
+          )
+          done()
+        })
+      })
+
+      it('should encrypt the object differently the next time', function (done) {
+        this.encryptor.encryptJson(this.testObject, (err, encrypted1) => {
+          expect(err).to.be.null
+          this.encryptor.encryptJson(this.testObject, (err, encrypted2) => {
+            expect(err).to.be.null
+            encrypted1.should.not.equal(encrypted2)
+            done()
+          })
+        })
+      })
+    })
+
+    describe('decrypt', function () {
+      it('should decrypt the string to get the same object', function (done) {
+        this.encryptor.encryptJson(this.testObject, (err, encrypted) => {
+          expect(err).to.be.null
+          this.encryptor.decryptToJson(encrypted, (err, decrypted) => {
+            expect(err).to.be.null
+            expect(decrypted).to.deep.equal(this.testObject)
+            done()
+          })
+        })
+      })
+
+      it('should not be able to decrypt 2015 string', function (done) {
+        this.encryptor.decryptToJson(this.encrypted2015, (err, decrypted) => {
+          expect(err).to.exist
+          expect(err.message).to.equal(
+            'unknown access-token-encryptor label 2015.1'
+          )
+          expect(decrypted).to.not.exist
+          done()
+        })
+      })
+
+      it('should not be able to decrypt a 2016 string', function (done) {
+        this.encryptor.decryptToJson(this.encrypted2016, (err, decrypted) => {
+          expect(err).to.exist
+          expect(err.message).to.equal(
+            'unknown access-token-encryptor label 2016.1'
+          )
+          expect(decrypted).to.not.exist
+          done()
+        })
+      })
+
+      it('should not be able to decrypt a 2019 string', function (done) {
+        this.encryptor.decryptToJson(this.encrypted2019, (err, decrypted) => {
+          expect(err).to.exist
+          expect(err.message).to.equal(
+            'unknown access-token-encryptor label 2019.1'
+          )
+          expect(decrypted).to.not.exist
+          done()
+        })
+      })
+
+      it('should decrypt an 2023 string to get the same object', function (done) {
+        this.encryptor.decryptToJson(this.encrypted2023, (err, decrypted) => {
+          expect(err).to.be.null
+          expect(decrypted).to.deep.equal(this.testObject)
+          done()
+        })
+      })
+
+      it('should return an error when decrypting an invalid label', function (done) {
+        this.encryptor.decryptToJson(this.badLabel, (err, decrypted) => {
+          expect(err).to.be.instanceof(Error)
+          expect(decrypted).to.be.undefined
+          done()
+        })
+      })
+
+      it('should return an error when decrypting an invalid key', function (done) {
+        this.encryptor.decryptToJson(this.badKey, (err, decrypted) => {
+          expect(err).to.be.instanceof(Error)
+          expect(decrypted).to.be.undefined
+          done()
+        })
+      })
+
+      it('should return an error when decrypting an invalid ciphertext', function (done) {
+        this.encryptor.decryptToJson(this.badCipherText, (err, decrypted) => {
+          expect(err).to.be.instanceof(Error)
+          expect(decrypted).to.be.undefined
+          done()
+        })
+      })
+    })
+  })
+
+  describe('async', function () {
+    describe('encrypt', function () {
+      it('should encrypt the object', async function () {
+        const encrypted = await this.encryptor.promises.encryptJson(
+          this.testObject
+        )
+        encrypted.should.match(
+          /^2023.1-v3:[0-9a-f]{32}:[a-zA-Z0-9=+/]+:[0-9a-f]{32}$/
+        )
+      })
+
+      it('should encrypt the object differently the next time', async function () {
+        const encrypted1 = await this.encryptor.promises.encryptJson(
+          this.testObject
+        )
+        const encrypted2 = await this.encryptor.promises.encryptJson(
+          this.testObject
+        )
+        encrypted1.should.not.equal(encrypted2)
+      })
+    })
+
+    describe('decrypt', function () {
+      it('should decrypt the string to get the same object', async function () {
+        const encrypted = await this.encryptor.promises.encryptJson(
+          this.testObject
+        )
+        const decrypted = await this.encryptor.promises.decryptToJson(encrypted)
+        expect(decrypted).to.deep.equal(this.testObject)
+      })
+
+      it('should not be able to decrypt 2015 string', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.encrypted2015)
+        ).to.eventually.be.rejectedWith(
+          'unknown access-token-encryptor label 2015.1'
+        )
+      })
+
+      it('should not be able to decrypt a 2016 string', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.encrypted2016)
+        ).to.be.rejectedWith('unknown access-token-encryptor label 2016.1')
+      })
+
+      it('should not be able to decrypt a 2019 string', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.encrypted2019)
+        ).to.be.rejectedWith('unknown access-token-encryptor label 2019.1')
+      })
+
+      it('should decrypt an 2023 string to get the same object', async function () {
+        const decrypted = await this.encryptor.promises.decryptToJson(
+          this.encrypted2023
+        )
+        expect(decrypted).to.deep.equal(this.testObject)
+      })
+
+      it('should return an error when decrypting an invalid label', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.badLabel)
+        ).to.be.rejectedWith('unknown access-token-encryptor label xxxxxx')
+      })
+
+      it('should return an error when decrypting an invalid key', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.badKey)
+        ).to.be.rejectedWith('unknown access-token-encryptor label 2015.1')
+      })
+
+      it('should return an error when decrypting an invalid ciphertext', async function () {
+        await expect(
+          this.encryptor.promises.decryptToJson(this.badCipherText)
+        ).to.be.rejectedWith('unknown access-token-encryptor label 2015.1')
+      })
+    })
+  })
+})

libraries/access-token-encryptor/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.backend.json",
+  "include": [
+    "**/*.js",
+    "**/*.cjs"
+  ]
+}

libraries/fetch-utils/.gitignore

@@ -0,0 +1,3 @@
+
+# managed by monorepo$ bin/update_build_scripts
+.npmrc

libraries/fetch-utils/.mocharc.json

@@ -0,0 +1,6 @@
+{
+  "ui": "bdd",
+  "recursive": "true",
+  "reporter": "spec",
+  "require": "test/setup.js"
+}

libraries/fetch-utils/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/fetch-utils/buildscript.txt

@@ -0,0 +1,10 @@
+fetch-utils
+--dependencies=None
+--docker-repos=gcr.io/overleaf-ops
+--env-add=
+--env-pass-through=
+--esmock-loader=False
+--is-library=True
+--node-version=20.18.2
+--public-repo=False
+--script-version=4.7.0

libraries/fetch-utils/index.js

@@ -0,0 +1,320 @@
+const _ = require('lodash')
+const { Readable } = require('node:stream')
+const OError = require('@overleaf/o-error')
+const fetch = require('node-fetch')
+const http = require('node:http')
+const https = require('node:https')
+
+/**
+ * @import { Response } from 'node-fetch'
+ */
+
+/**
+ * Make a request and return the parsed JSON response.
+ *
+ * @param {string | URL} url - request URL
+ * @param {any} [opts] - fetch options
+ * @return {Promise<any>} the parsed JSON response
+ * @throws {RequestFailedError} if the response has a failure status code
+ */
+async function fetchJson(url, opts = {}) {
+  const { json } = await fetchJsonWithResponse(url, opts)
+  return json
+}
+
+async function fetchJsonWithResponse(url, opts = {}) {
+  const { fetchOpts } = parseOpts(opts)
+  fetchOpts.headers = fetchOpts.headers ?? {}
+  fetchOpts.headers.Accept = fetchOpts.headers.Accept ?? 'application/json'
+
+  const response = await performRequest(url, fetchOpts)
+  if (!response.ok) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body)
+  }
+
+  const json = await response.json()
+  return { json, response }
+}
+
+/**
+ * Make a request and return a stream.
+ *
+ * If the response body is destroyed, the request is aborted.
+ *
+ * @param {string | URL} url - request URL
+ * @param {any} [opts] - fetch options
+ * @return {Promise<Readable>}
+ * @throws {RequestFailedError} if the response has a failure status code
+ */
+async function fetchStream(url, opts = {}) {
+  const { stream } = await fetchStreamWithResponse(url, opts)
+  return stream
+}
+
+async function fetchStreamWithResponse(url, opts = {}) {
+  const { fetchOpts, abortController } = parseOpts(opts)
+  const response = await performRequest(url, fetchOpts)
+
+  if (!response.ok) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body)
+  }
+
+  abortOnDestroyedResponse(abortController, response)
+
+  const stream = response.body
+  return { stream, response }
+}
+
+/**
+ * Make a request and discard the response.
+ *
+ * @param {string | URL} url - request URL
+ * @param {any} [opts] - fetch options
+ * @return {Promise<Response>}
+ * @throws {RequestFailedError} if the response has a failure status code
+ */
+async function fetchNothing(url, opts = {}) {
+  const { fetchOpts } = parseOpts(opts)
+  const response = await performRequest(url, fetchOpts)
+  if (!response.ok) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body)
+  }
+  await discardResponseBody(response)
+  return response
+}
+
+/**
+ * Make a request and extract the redirect from the response.
+ *
+ * @param {string | URL} url - request URL
+ * @param {any} [opts] - fetch options
+ * @return {Promise<string>}
+ * @throws {RequestFailedError} if the response has a non redirect status code or missing Location header
+ */
+async function fetchRedirect(url, opts = {}) {
+  const { location } = await fetchRedirectWithResponse(url, opts)
+  return location
+}
+
+/**
+ * Make a request and extract the redirect from the response.
+ *
+ * @param {string | URL} url - request URL
+ * @param {object} opts - fetch options
+ * @return {Promise<{location: string, response: Response}>}
+ * @throws {RequestFailedError} if the response has a non redirect status code or missing Location header
+ */
+async function fetchRedirectWithResponse(url, opts = {}) {
+  const { fetchOpts } = parseOpts(opts)
+  fetchOpts.redirect = 'manual'
+  const response = await performRequest(url, fetchOpts)
+  if (response.status < 300 || response.status >= 400) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body)
+  }
+  const location = response.headers.get('Location')
+  if (!location) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body).withCause(
+      new OError('missing Location response header on 3xx response', {
+        headers: Object.fromEntries(response.headers.entries()),
+      })
+    )
+  }
+  await discardResponseBody(response)
+  return { location, response }
+}
+
+/**
+ * Make a request and return a string.
+ *
+ * @param {string | URL} url - request URL
+ * @param {any} [opts] - fetch options
+ * @return {Promise<string>}
+ * @throws {RequestFailedError} if the response has a failure status code
+ */
+async function fetchString(url, opts = {}) {
+  const { body } = await fetchStringWithResponse(url, opts)
+  return body
+}
+
+async function fetchStringWithResponse(url, opts = {}) {
+  const { fetchOpts } = parseOpts(opts)
+  const response = await performRequest(url, fetchOpts)
+  if (!response.ok) {
+    const body = await maybeGetResponseBody(response)
+    throw new RequestFailedError(url, opts, response, body)
+  }
+  const body = await response.text()
+  return { body, response }
+}
+
+class RequestFailedError extends OError {
+  constructor(url, opts, response, body) {
+    super('request failed', {
+      url,
+      method: opts.method ?? 'GET',
+      status: response.status,
+    })
+
+    this.response = response
+    if (body != null) {
+      this.body = body
+    }
+  }
+}
+
+function parseOpts(opts) {
+  const fetchOpts = _.omit(opts, ['json', 'signal', 'basicAuth'])
+  if (opts.json) {
+    setupJsonBody(fetchOpts, opts.json)
+  }
+  if (opts.basicAuth) {
+    setupBasicAuth(fetchOpts, opts.basicAuth)
+  }
+
+  const abortController = new AbortController()
+  fetchOpts.signal = abortController.signal
+  if (opts.signal) {
+    abortOnSignal(abortController, opts.signal)
+  }
+  if (opts.body instanceof Readable) {
+    abortOnDestroyedRequest(abortController, fetchOpts.body)
+  }
+  return { fetchOpts, abortController }
+}
+
+function setupJsonBody(fetchOpts, json) {
+  fetchOpts.body = JSON.stringify(json)
+  fetchOpts.headers = fetchOpts.headers ?? {}
+  fetchOpts.headers['Content-Type'] = 'application/json'
+}
+
+function setupBasicAuth(fetchOpts, basicAuth) {
+  fetchOpts.headers = fetchOpts.headers ?? {}
+  fetchOpts.headers.Authorization =
+    'Basic ' +
+    Buffer.from(`${basicAuth.user}:${basicAuth.password}`).toString('base64')
+}
+
+function abortOnSignal(abortController, signal) {
+  const listener = () => {
+    abortController.abort(signal.reason)
+  }
+  if (signal.aborted) {
+    abortController.abort(signal.reason)
+  }
+  signal.addEventListener('abort', listener)
+}
+
+function abortOnDestroyedRequest(abortController, stream) {
+  stream.on('close', () => {
+    if (!stream.readableEnded) {
+      abortController.abort()
+    }
+  })
+}
+
+function abortOnDestroyedResponse(abortController, response) {
+  response.body.on('close', () => {
+    if (!response.bodyUsed) {
+      abortController.abort()
+    }
+  })
+}
+
+async function performRequest(url, fetchOpts) {
+  let response
+  try {
+    response = await fetch(url, fetchOpts)
+  } catch (err) {
+    if (fetchOpts.body instanceof Readable) {
+      fetchOpts.body.destroy()
+    }
+    throw OError.tag(err, err.message, {
+      url,
+      method: fetchOpts.method ?? 'GET',
+    })
+  }
+  if (fetchOpts.body instanceof Readable) {
+    response.body.on('close', () => {
+      if (!fetchOpts.body.readableEnded) {
+        fetchOpts.body.destroy()
+      }
+    })
+  }
+  return response
+}
+
+async function discardResponseBody(response) {
+  // eslint-disable-next-line no-unused-vars
+  for await (const chunk of response.body) {
+    // discard the body
+  }
+}
+
+/**
+ * @param {Response} response
+ */
+async function maybeGetResponseBody(response) {
+  try {
+    return await response.text()
+  } catch (err) {
+    return null
+  }
+}
+
+// Define custom http and https agents with support for connect timeouts
+
+class ConnectTimeoutError extends OError {
+  constructor(options) {
+    super('connect timeout', options)
+  }
+}
+
+function withTimeout(createConnection, options, callback) {
+  if (options.connectTimeout) {
+    // Wrap createConnection in a timeout
+    const timer = setTimeout(() => {
+      socket.destroy(new ConnectTimeoutError(options))
+    }, options.connectTimeout)
+    const socket = createConnection(options, (err, stream) => {
+      clearTimeout(timer)
+      callback(err, stream)
+    })
+    return socket
+  } else {
+    // Fallback to default createConnection
+    return createConnection(options, callback)
+  }
+}
+
+class CustomHttpAgent extends http.Agent {
+  createConnection(options, callback) {
+    return withTimeout(super.createConnection.bind(this), options, callback)
+  }
+}
+class CustomHttpsAgent extends https.Agent {
+  createConnection(options, callback) {
+    return withTimeout(super.createConnection.bind(this), options, callback)
+  }
+}
+
+module.exports = {
+  fetchJson,
+  fetchJsonWithResponse,
+  fetchStream,
+  fetchStreamWithResponse,
+  fetchNothing,
+  fetchRedirect,
+  fetchRedirectWithResponse,
+  fetchString,
+  fetchStringWithResponse,
+  RequestFailedError,
+  ConnectTimeoutError,
+  CustomHttpAgent,
+  CustomHttpsAgent,
+}

libraries/fetch-utils/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@overleaf/fetch-utils",
+  "version": "0.1.0",
+  "description": "utilities for node-fetch",
+  "main": "index.js",
+  "scripts": {
+    "test": "npm run lint && npm run format && npm run types:check && npm run test:unit",
+    "lint": "eslint --ext .js --ext .cjs --ext .ts --max-warnings 0 --format unix .",
+    "lint:fix": "eslint --fix --ext .js --ext .cjs --ext .ts .",
+    "format": "prettier --list-different $PWD/'**/*.{js,cjs,ts}'",
+    "format:fix": "prettier --write $PWD/'**/*.{js,cjs,ts}'",
+    "test:ci": "npm run test:unit",
+    "test:unit": "mocha --exit test/**/*.{js,cjs}",
+    "types:check": "tsc --noEmit"
+  },
+  "author": "Overleaf (https://www.overleaf.com)",
+  "license": "AGPL-3.0-only",
+  "devDependencies": {
+    "@types/node-fetch": "^2.6.11",
+    "body-parser": "^1.20.3",
+    "chai": "^4.3.6",
+    "chai-as-promised": "^7.1.1",
+    "express": "^4.21.2",
+    "mocha": "^11.1.0",
+    "typescript": "^5.0.4"
+  },
+  "dependencies": {
+    "@overleaf/o-error": "*",
+    "lodash": "^4.17.21",
+    "node-fetch": "^2.7.0",
+    "selfsigned": "^2.4.1"
+  }
+}

libraries/fetch-utils/test/setup.js

@@ -0,0 +1,4 @@
+const chai = require('chai')
+const chaiAsPromised = require('chai-as-promised')
+
+chai.use(chaiAsPromised)

libraries/fetch-utils/test/unit/FetchUtilsTests.js

@@ -0,0 +1,414 @@
+const { expect } = require('chai')
+const { FetchError, AbortError } = require('node-fetch')
+const { Readable } = require('node:stream')
+const { once } = require('node:events')
+const { TestServer } = require('./helpers/TestServer')
+const selfsigned = require('selfsigned')
+const {
+  fetchJson,
+  fetchStream,
+  fetchNothing,
+  fetchRedirect,
+  fetchString,
+  RequestFailedError,
+  CustomHttpAgent,
+  CustomHttpsAgent,
+} = require('../..')
+
+const HTTP_PORT = 30001
+const HTTPS_PORT = 30002
+
+const attrs = [{ name: 'commonName', value: 'example.com' }]
+const pems = selfsigned.generate(attrs, { days: 365 })
+
+const PRIVATE_KEY = pems.private
+const PUBLIC_CERT = pems.cert
+
+const dns = require('node:dns')
+const _originalLookup = dns.lookup
+// Custom DNS resolver function
+dns.lookup = (hostname, options, callback) => {
+  if (hostname === 'example.com') {
+    // If the hostname is our test case, return the ip address for the test server
+    if (options?.all) {
+      callback(null, [{ address: '127.0.0.1', family: 4 }])
+    } else {
+      callback(null, '127.0.0.1', 4)
+    }
+  } else {
+    // Otherwise, use the default lookup
+    _originalLookup(hostname, options, callback)
+  }
+}
+
+describe('fetch-utils', function () {
+  before(async function () {
+    this.server = new TestServer()
+    await this.server.start(HTTP_PORT, HTTPS_PORT, {
+      key: PRIVATE_KEY,
+      cert: PUBLIC_CERT,
+    })
+    this.url = path => `http://example.com:${HTTP_PORT}${path}`
+    this.httpsUrl = path => `https://example.com:${HTTPS_PORT}${path}`
+  })
+
+  beforeEach(function () {
+    this.server.lastReq = undefined
+  })
+
+  after(async function () {
+    await this.server.stop()
+  })
+
+  describe('fetchJson', function () {
+    it('parses a JSON response', async function () {
+      const json = await fetchJson(this.url('/json/hello'))
+      expect(json).to.deep.equal({ msg: 'hello' })
+    })
+
+    it('parses JSON in the request', async function () {
+      const json = await fetchJson(this.url('/json/add'), {
+        method: 'POST',
+        json: { a: 2, b: 3 },
+      })
+      expect(json).to.deep.equal({ sum: 5 })
+    })
+
+    it('accepts stringified JSON as body', async function () {
+      const json = await fetchJson(this.url('/json/add'), {
+        method: 'POST',
+        body: JSON.stringify({ a: 2, b: 3 }),
+        headers: { 'Content-Type': 'application/json' },
+      })
+      expect(json).to.deep.equal({ sum: 5 })
+    })
+
+    it('throws a FetchError when the payload is not JSON', async function () {
+      await expect(fetchJson(this.url('/hello'))).to.be.rejectedWith(FetchError)
+    })
+
+    it('aborts the request if JSON parsing fails', async function () {
+      await expect(fetchJson(this.url('/large'))).to.be.rejectedWith(FetchError)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('handles errors when the payload is JSON', async function () {
+      await expect(fetchJson(this.url('/json/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('handles errors when the payload is not JSON', async function () {
+      await expect(fetchJson(this.url('/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('supports abort signals', async function () {
+      await expect(
+        abortOnceReceived(
+          signal => fetchJson(this.url('/hang'), { signal }),
+          this.server
+        )
+      ).to.be.rejectedWith(AbortError)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('supports basic auth', async function () {
+      const json = await fetchJson(this.url('/json/basic-auth'), {
+        basicAuth: { user: 'user', password: 'pass' },
+      })
+      expect(json).to.deep.equal({ key: 'verysecret' })
+    })
+
+    it("destroys the request body if it doesn't get consumed", async function () {
+      const stream = Readable.from(infiniteIterator())
+      await fetchJson(this.url('/json/ignore-request'), {
+        method: 'POST',
+        body: stream,
+      })
+      expect(stream.destroyed).to.be.true
+    })
+  })
+
+  describe('fetchStream', function () {
+    it('returns a stream', async function () {
+      const stream = await fetchStream(this.url('/large'))
+      const text = await streamToString(stream)
+      expect(text).to.equal(this.server.largePayload)
+    })
+
+    it('aborts the request when the stream is destroyed', async function () {
+      const stream = await fetchStream(this.url('/large'))
+      stream.destroy()
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('aborts the request when the request body is destroyed before transfer', async function () {
+      const stream = Readable.from(infiniteIterator())
+      const promise = fetchStream(this.url('/hang'), {
+        method: 'POST',
+        body: stream,
+      })
+      stream.destroy()
+      await expect(promise).to.be.rejectedWith(AbortError)
+      await wait(80)
+      expect(this.server.lastReq).to.be.undefined
+    })
+
+    it('aborts the request when the request body is destroyed during transfer', async function () {
+      const stream = Readable.from(infiniteIterator())
+      // Note: this test won't work on `/hang`
+      const promise = fetchStream(this.url('/sink'), {
+        method: 'POST',
+        body: stream,
+      })
+      await once(this.server.events, 'request-received')
+      stream.destroy()
+      await expect(promise).to.be.rejectedWith(AbortError)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('handles errors', async function () {
+      await expect(fetchStream(this.url('/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('supports abort signals', async function () {
+      await expect(
+        abortOnceReceived(
+          signal => fetchStream(this.url('/hang'), { signal }),
+          this.server
+        )
+      ).to.be.rejectedWith(AbortError)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('destroys the request body when an error occurs', async function () {
+      const stream = Readable.from(infiniteIterator())
+      await expect(
+        abortOnceReceived(
+          signal =>
+            fetchStream(this.url('/hang'), {
+              method: 'POST',
+              body: stream,
+              signal,
+            }),
+          this.server
+        )
+      ).to.be.rejectedWith(AbortError)
+      expect(stream.destroyed).to.be.true
+    })
+  })
+
+  describe('fetchNothing', function () {
+    it('closes the connection', async function () {
+      await fetchNothing(this.url('/large'))
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('aborts the request when the request body is destroyed before transfer', async function () {
+      const stream = Readable.from(infiniteIterator())
+      const promise = fetchNothing(this.url('/hang'), {
+        method: 'POST',
+        body: stream,
+      })
+      stream.destroy()
+      await expect(promise).to.be.rejectedWith(AbortError)
+      expect(this.server.lastReq).to.be.undefined
+    })
+
+    it('aborts the request when the request body is destroyed during transfer', async function () {
+      const stream = Readable.from(infiniteIterator())
+      // Note: this test won't work on `/hang`
+      const promise = fetchNothing(this.url('/sink'), {
+        method: 'POST',
+        body: stream,
+      })
+      await once(this.server.events, 'request-received')
+      stream.destroy()
+      await expect(promise).to.be.rejectedWith(AbortError)
+      await wait(80)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it("doesn't abort the request if the request body ends normally", async function () {
+      const stream = Readable.from('hello there')
+      await fetchNothing(this.url('/sink'), { method: 'POST', body: stream })
+    })
+
+    it('handles errors', async function () {
+      await expect(fetchNothing(this.url('/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('supports abort signals', async function () {
+      await expect(
+        abortOnceReceived(
+          signal => fetchNothing(this.url('/hang'), { signal }),
+          this.server
+        )
+      ).to.be.rejectedWith(AbortError)
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('destroys the request body when an error occurs', async function () {
+      const stream = Readable.from(infiniteIterator())
+      await expect(
+        abortOnceReceived(
+          signal =>
+            fetchNothing(this.url('/hang'), {
+              method: 'POST',
+              body: stream,
+              signal,
+            }),
+          this.server
+        )
+      ).to.be.rejectedWith(AbortError)
+      expect(stream.destroyed).to.be.true
+    })
+  })
+
+  describe('fetchString', function () {
+    it('returns a string', async function () {
+      const body = await fetchString(this.url('/hello'))
+      expect(body).to.equal('hello')
+    })
+
+    it('handles errors', async function () {
+      await expect(fetchString(this.url('/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+  })
+
+  describe('fetchRedirect', function () {
+    it('returns the immediate redirect', async function () {
+      const body = await fetchRedirect(this.url('/redirect/1'))
+      expect(body).to.equal(this.url('/redirect/2'))
+    })
+
+    it('rejects status 200', async function () {
+      await expect(fetchRedirect(this.url('/hello'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('rejects empty redirect', async function () {
+      await expect(fetchRedirect(this.url('/redirect/empty-location')))
+        .to.be.rejectedWith(RequestFailedError)
+        .and.eventually.have.property('cause')
+        .and.to.have.property('message')
+        .to.equal('missing Location response header on 3xx response')
+      await expectRequestAborted(this.server.lastReq)
+    })
+
+    it('handles errors', async function () {
+      await expect(fetchRedirect(this.url('/500'))).to.be.rejectedWith(
+        RequestFailedError
+      )
+      await expectRequestAborted(this.server.lastReq)
+    })
+  })
+
+  describe('CustomHttpAgent', function () {
+    it('makes an http request successfully', async function () {
+      const agent = new CustomHttpAgent({ connectTimeout: 100 })
+      const body = await fetchString(this.url('/hello'), { agent })
+      expect(body).to.equal('hello')
+    })
+
+    it('times out when accessing a non-routable address', async function () {
+      const agent = new CustomHttpAgent({ connectTimeout: 10 })
+      await expect(fetchString('http://10.255.255.255/', { agent }))
+        .to.be.rejectedWith(FetchError)
+        .and.eventually.have.property('message')
+        .and.to.equal(
+          'request to http://10.255.255.255/ failed, reason: connect timeout'
+        )
+    })
+  })
+
+  describe('CustomHttpsAgent', function () {
+    it('makes an https request successfully', async function () {
+      const agent = new CustomHttpsAgent({
+        connectTimeout: 100,
+        ca: PUBLIC_CERT,
+      })
+      const body = await fetchString(this.httpsUrl('/hello'), { agent })
+      expect(body).to.equal('hello')
+    })
+
+    it('rejects an untrusted server', async function () {
+      const agent = new CustomHttpsAgent({
+        connectTimeout: 100,
+      })
+      await expect(fetchString(this.httpsUrl('/hello'), { agent }))
+        .to.be.rejectedWith(FetchError)
+        .and.eventually.have.property('code')
+        .and.to.equal('DEPTH_ZERO_SELF_SIGNED_CERT')
+    })
+
+    it('times out when accessing a non-routable address', async function () {
+      const agent = new CustomHttpsAgent({ connectTimeout: 10 })
+      await expect(fetchString('https://10.255.255.255/', { agent }))
+        .to.be.rejectedWith(FetchError)
+        .and.eventually.have.property('message')
+        .and.to.equal(
+          'request to https://10.255.255.255/ failed, reason: connect timeout'
+        )
+    })
+  })
+})
+
+async function streamToString(stream) {
+  let s = ''
+  for await (const chunk of stream) {
+    s += chunk
+  }
+  return s
+}
+
+async function* infiniteIterator() {
+  let i = 1
+  while (true) {
+    yield `chunk ${i++}\n`
+  }
+}
+
+/**
+ * @param {(signal: AbortSignal) => Promise<any>} func
+ * @param {TestServer} server
+ */
+async function abortOnceReceived(func, server) {
+  const controller = new AbortController()
+  const promise = func(controller.signal)
+  await once(server.events, 'request-received')
+  controller.abort()
+  return await promise
+}
+
+async function expectRequestAborted(req) {
+  if (!req.destroyed) {
+    try {
+      await once(req, 'close')
+    } catch (err) {
+      // `once` throws if req emits an 'error' event.
+      // We ignore `Error: aborted` when the request is aborted.
+      if (err.message !== 'aborted') {
+        throw err
+      }
+    }
+  }
+  expect(req.destroyed).to.be.true
+}
+
+const wait = ms => new Promise(resolve => setTimeout(resolve, ms))

libraries/fetch-utils/test/unit/helpers/TestServer.js

@@ -0,0 +1,130 @@
+const express = require('express')
+const bodyParser = require('body-parser')
+const { EventEmitter } = require('node:events')
+const http = require('node:http')
+const https = require('node:https')
+const { promisify } = require('node:util')
+
+class TestServer {
+  constructor() {
+    this.app = express()
+    this.events = new EventEmitter()
+
+    this.app.use(bodyParser.json())
+    this.app.use((req, res, next) => {
+      this.events.emit('request-received')
+      this.lastReq = req
+      next()
+    })
+
+    // Plain text endpoints
+
+    this.app.get('/hello', (req, res) => {
+      res.send('hello')
+    })
+
+    this.largePayload = 'x'.repeat(16 * 1024 * 1024)
+    this.app.get('/large', (req, res) => {
+      res.send(this.largePayload)
+    })
+
+    this.app.get('/204', (req, res) => {
+      res.status(204).end()
+    })
+
+    this.app.get('/empty', (req, res) => {
+      res.end()
+    })
+
+    this.app.get('/500', (req, res) => {
+      res.sendStatus(500)
+    })
+
+    this.app.post('/sink', (req, res) => {
+      req.on('data', () => {})
+      req.on('end', () => {
+        res.status(204).end()
+      })
+    })
+
+    // JSON endpoints
+
+    this.app.get('/json/hello', (req, res) => {
+      res.json({ msg: 'hello' })
+    })
+
+    this.app.post('/json/add', (req, res) => {
+      const { a, b } = req.body
+      res.json({ sum: a + b })
+    })
+
+    this.app.get('/json/500', (req, res) => {
+      res.status(500).json({ error: 'Internal server error' })
+    })
+
+    this.app.get('/json/basic-auth', (req, res) => {
+      const expectedAuth =
+        'Basic ' + Buffer.from('user:pass').toString('base64')
+      if (req.headers.authorization === expectedAuth) {
+        res.json({ key: 'verysecret' })
+      } else {
+        res.status(401).json({ error: 'unauthorized' })
+      }
+    })
+
+    this.app.post('/json/ignore-request', (req, res) => {
+      res.json({ msg: 'hello' })
+    })
+
+    // Never returns
+
+    this.app.get('/hang', (req, res) => {})
+    this.app.post('/hang', (req, res) => {})
+
+    // Redirect
+
+    this.app.get('/redirect/1', (req, res) => {
+      res.redirect('/redirect/2')
+    })
+    this.app.get('/redirect/2', (req, res) => {
+      res.send('body after redirect')
+    })
+    this.app.get('/redirect/empty-location', (req, res) => {
+      res.sendStatus(302)
+    })
+  }
+
+  start(port, httpsPort, httpsOptions) {
+    const startHttp = new Promise((resolve, reject) => {
+      this.server = http.createServer(this.app).listen(port, err => {
+        if (err) {
+          reject(err)
+        } else {
+          resolve()
+        }
+      })
+    })
+    const startHttps = new Promise((resolve, reject) => {
+      this.https_server = https
+        .createServer(httpsOptions, this.app)
+        .listen(httpsPort, err => {
+          if (err) {
+            reject(err)
+          } else {
+            resolve()
+          }
+        })
+    })
+    return Promise.all([startHttp, startHttps])
+  }
+
+  stop() {
+    const stopHttp = promisify(this.server.close).bind(this.server)
+    const stopHttps = promisify(this.https_server.close).bind(this.https_server)
+    this.server.closeAllConnections()
+    this.https_server.closeAllConnections()
+    return Promise.all([stopHttp(), stopHttps()])
+  }
+}
+
+module.exports = { TestServer }

libraries/fetch-utils/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.backend.json",
+  "include": [
+    "**/*.js",
+    "**/*.cjs"
+  ]
+}

libraries/logger/.gitignore

@@ -0,0 +1,3 @@
+node_modules
+
+.npmrc

libraries/logger/.mocharc.json

@@ -0,0 +1,3 @@
+{
+  "require": "test/setup.js"
+}

libraries/logger/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/logger/CHANGELOG.md

@@ -0,0 +1,10 @@
+## v3.1.1
+
+* Handle malformed requests in the req serializer
+
+## v3.0.0
+
+* Improve logging in Google Cloud Platform. Set environment variable `GCP_LOGGING=true` to enable.
+
+This version of the metrics module only works with versions of the `@overleaf/metrics` module greater than v4.0.0
+

libraries/logger/LICENSE.txt

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  Developers that use our General Public Licenses protect your rights
+with two steps: (1) assert copyright on the software, and (2) offer
+you this License which gives you legal permission to copy, distribute
+and/or modify the software.
+
+  A secondary benefit of defending all users' freedom is that
+improvements made in alternate versions of the program, if they
+receive widespread use, become available for other developers to
+incorporate.  Many developers of free software are heartened and
+encouraged by the resulting cooperation.  However, in the case of
+software used on network servers, this result may fail to come about.
+The GNU General Public License permits making a modified version and
+letting the public access it on a server without ever releasing its
+source code to the public.
+
+  The GNU Affero General Public License is designed specifically to
+ensure that, in such cases, the modified source code becomes available
+to the community.  It requires the operator of a network server to
+provide the source code of the modified version running there to the
+users of that server.  Therefore, public use of a modified version, on
+a publicly accessible server, gives the public access to the source
+code of the modified version.
+
+  An older license, called the Affero General Public License and
+published by Affero, was designed to accomplish similar goals.  This is
+a different license, not a version of the Affero GPL, but Affero has
+released a new version of the Affero GPL which permits relicensing under
+this license.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU Affero General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
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+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.

libraries/logger/buildscript.txt

@@ -0,0 +1,10 @@
+logger
+--dependencies=None
+--docker-repos=gcr.io/overleaf-ops
+--env-add=
+--env-pass-through=
+--esmock-loader=False
+--is-library=True
+--node-version=20.18.2
+--public-repo=False
+--script-version=4.7.0

libraries/logger/gcp-manager.js

@@ -0,0 +1,133 @@
+const bunyan = require('bunyan')
+
+/**
+ * When we copy log entry fields, omit some bunyan core fields that are not
+ * interesting, that have a special meaning in GCP, or that we will process
+ * separately.
+ */
+const ENTRY_FIELDS_TO_OMIT = [
+  'level',
+  'name',
+  'hostname',
+  'v',
+  'pid',
+  'msg',
+  'err',
+  'error',
+  'req',
+  'res',
+]
+
+/**
+ * Convert a bunyan log entry to a format that GCP understands
+ */
+function convertLogEntry(entry) {
+  const gcpEntry = omit(entry, ENTRY_FIELDS_TO_OMIT)
+
+  // Error information. In GCP, the stack trace goes in the message property.
+  // This enables the error reporting feature.
+  const err = entry.err || entry.error
+  if (err) {
+    if (err.info) {
+      Object.assign(gcpEntry, err.info)
+    }
+    if (err.code) {
+      gcpEntry.code = err.code
+    }
+    if (err.signal) {
+      gcpEntry.signal = err.signal
+    }
+    const stack = err.stack
+    if (stack && stack !== '(no stack)') {
+      gcpEntry.message = stack
+    } else if (err.message) {
+      gcpEntry.message = err.message
+    }
+    if (entry.name) {
+      gcpEntry.serviceContext = { service: entry.name }
+    }
+  }
+
+  // Log message
+  if (entry.msg) {
+    if (gcpEntry.message) {
+      // A message has already been extracted from the error. Keep the extra
+      // message in the msg property.
+      gcpEntry.msg = entry.msg
+    } else {
+      gcpEntry.message = entry.msg
+    }
+  }
+
+  // Severity
+  if (entry.level) {
+    gcpEntry.severity = bunyan.nameFromLevel[entry.level]
+  }
+
+  // HTTP request information
+  if (entry.req || entry.res || entry.responseTimeMs) {
+    const httpRequest = {}
+    if (entry.req) {
+      const req = entry.req
+      httpRequest.requestMethod = req.method
+      httpRequest.requestUrl = req.url
+      httpRequest.remoteIp = req.remoteAddress
+      if (req.headers) {
+        if (req.headers['content-length']) {
+          httpRequest.requestSize = parseInt(req.headers['content-length'], 10)
+        }
+        httpRequest.userAgent = req.headers['user-agent']
+        httpRequest.referer = req.headers.referer
+      }
+    }
+
+    if (entry.res) {
+      const res = entry.res
+      httpRequest.status = res.statusCode
+      if (res.headers && res.headers['content-length']) {
+        if (res.headers['content-length']) {
+          httpRequest.responseSize = parseInt(res.headers['content-length'], 10)
+        }
+      }
+    }
+
+    if (entry.responseTimeMs) {
+      const responseTimeSec = entry.responseTimeMs / 1000
+      httpRequest.latency = `${responseTimeSec}s`
+    }
+    gcpEntry.httpRequest = httpRequest
+  }
+
+  // Labels are indexed in GCP. We copy the project, doc and user ids to labels to enable fast filtering
+  const projectId =
+    gcpEntry.projectId ||
+    gcpEntry.project_id ||
+    (entry.req && entry.req.projectId)
+  const userId =
+    gcpEntry.userId || gcpEntry.user_id || (entry.req && entry.req.userId)
+  const docId =
+    gcpEntry.docId || gcpEntry.doc_id || (entry.req && entry.req.docId)
+  if (projectId || userId || docId) {
+    const labels = {}
+    if (projectId) {
+      labels.projectId = projectId
+    }
+    if (userId) {
+      labels.userId = userId
+    }
+    if (docId) {
+      labels.docId = docId
+    }
+    gcpEntry['logging.googleapis.com/labels'] = labels
+  }
+
+  return gcpEntry
+}
+
+function omit(obj, excludedFields) {
+  return Object.fromEntries(
+    Object.entries(obj).filter(([key]) => !excludedFields.includes(key))
+  )
+}
+
+module.exports = { convertLogEntry }

libraries/logger/index.js

@@ -0,0 +1 @@
+module.exports = require('./logging-manager.js')

libraries/logger/log-level-checker.js

@@ -0,0 +1,60 @@
+const { fetchString } = require('@overleaf/fetch-utils')
+const fs = require('node:fs')
+
+class LogLevelChecker {
+  constructor(logger, defaultLevel) {
+    this.logger = logger
+    this.defaultLevel = defaultLevel
+  }
+
+  start() {
+    // check for log level override on startup
+    this.checkLogLevel()
+    // re-check log level every minute
+    this.checkInterval = setInterval(this.checkLogLevel.bind(this), 1000 * 60)
+    this.checkInterval.unref()
+  }
+
+  stop() {
+    clearInterval(this.checkInterval)
+  }
+
+  async checkLogLevel() {
+    try {
+      const end = await this.getTracingEndTime()
+      if (end > Date.now()) {
+        this.logger.level('trace')
+      } else {
+        this.logger.level(this.defaultLevel)
+      }
+    } catch (e) {
+      this.logger.level(this.defaultLevel)
+    }
+  }
+
+  async getTracingEndTime() {
+    return 0
+  }
+}
+
+class FileLogLevelChecker extends LogLevelChecker {
+  async getTracingEndTime() {
+    const strEndTime = await fs.promises.readFile('/logging/tracingEndTime')
+    return parseInt(strEndTime, 10)
+  }
+}
+
+class GCEMetadataLogLevelChecker extends LogLevelChecker {
+  async getTracingEndTime() {
+    const options = {
+      headers: {
+        'Metadata-Flavor': 'Google',
+      },
+    }
+    const uri = `http://metadata.google.internal/computeMetadata/v1/project/attributes/${this.logger.fields.name}-setLogLevelEndTime`
+    const strEndTime = await fetchString(uri, options)
+    return parseInt(strEndTime, 10)
+  }
+}
+
+module.exports = { FileLogLevelChecker, GCEMetadataLogLevelChecker }

libraries/logger/logging-manager.js

@@ -0,0 +1,186 @@
+const Stream = require('node:stream')
+const bunyan = require('bunyan')
+const GCPManager = require('./gcp-manager')
+const Serializers = require('./serializers')
+const {
+  FileLogLevelChecker,
+  GCEMetadataLogLevelChecker,
+} = require('./log-level-checker')
+
+const LoggingManager = {
+  /**
+   * @param {string} name - The name of the logger
+   */
+  initialize(name) {
+    this.isProduction =
+      (process.env.NODE_ENV || '').toLowerCase() === 'production'
+    const isTest = (process.env.NODE_ENV || '').toLowerCase() === 'test'
+    this.defaultLevel =
+      process.env.LOG_LEVEL ||
+      (this.isProduction ? 'info' : isTest ? 'fatal' : 'debug')
+    this.loggerName = name
+    this.logger = bunyan.createLogger({
+      name,
+      serializers: {
+        err: Serializers.err,
+        error: Serializers.err,
+        req: Serializers.req,
+        res: Serializers.res,
+      },
+      streams: [this._getOutputStreamConfig()],
+    })
+    this._setupRingBuffer()
+    this._setupLogLevelChecker()
+    return this
+  },
+
+  /**
+   * @param {Record<string, any>|string} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message] - Optional message
+   * @signature `debug(attributes, message)`
+   * @signature `debug(message)`
+   */
+  debug(attributes, message, ...args) {
+    return this.logger.debug(attributes, message, ...args)
+  },
+
+  /**
+   * @param {Record<string, any>|string} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message]
+   * @signature `info(attributes, message)`
+   * @signature `info(message)`
+   */
+  info(attributes, message, ...args) {
+    return this.logger.info(attributes, message, ...args)
+  },
+
+  /**
+   * @param {Record<string, any>} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message]
+   */
+  error(attributes, message, ...args) {
+    if (this.ringBuffer !== null && Array.isArray(this.ringBuffer.records)) {
+      attributes.logBuffer = this.ringBuffer.records.filter(function (record) {
+        return record.level !== 50
+      })
+    }
+    this.logger.error(attributes, message, ...Array.from(args))
+  },
+
+  /**
+   * Alias to the error method.
+   * @param {Record<string, any>} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message]
+   */
+  err(attributes, message, ...args) {
+    return this.error(attributes, message, ...args)
+  },
+
+  /**
+   * @param {Record<string, any>|string} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message]
+   * @signature `warn(attributes, message)`
+   * @signature `warn(message)`
+   */
+  warn(attributes, message, ...args) {
+    return this.logger.warn(attributes, message, ...args)
+  },
+
+  /**
+   * @param {Record<string, any>} attributes - Attributes to log (nice serialization for err, req, res)
+   * @param {string} [message]
+   */
+  fatal(attributes, message) {
+    this.logger.fatal(attributes, message)
+  },
+
+  _getOutputStreamConfig() {
+    switch (process.env.LOGGING_FORMAT) {
+      case 'gke': {
+        const stream = new Stream.Writable({
+          objectMode: true,
+          write(entry, encoding, callback) {
+            const gcpEntry = GCPManager.convertLogEntry(entry)
+            // eslint-disable-next-line no-console
+            console.log(JSON.stringify(gcpEntry, bunyan.safeCycles()))
+            setImmediate(callback)
+          },
+        })
+        return { level: this.defaultLevel, type: 'raw', stream }
+      }
+      case 'gce': {
+        const { LoggingBunyan } = require('@google-cloud/logging-bunyan')
+        return new LoggingBunyan({
+          logName: this.loggerName,
+          serviceContext: { service: this.loggerName },
+        }).stream(this.defaultLevel)
+      }
+      default: {
+        return { level: this.defaultLevel, stream: process.stdout }
+      }
+    }
+  },
+
+  _setupRingBuffer() {
+    this.ringBufferSize = parseInt(process.env.LOG_RING_BUFFER_SIZE) || 0
+    if (this.ringBufferSize > 0) {
+      this.ringBuffer = new bunyan.RingBuffer({ limit: this.ringBufferSize })
+      this.logger.addStream({
+        level: 'trace',
+        type: 'raw',
+        stream: this.ringBuffer,
+      })
+    } else {
+      this.ringBuffer = null
+    }
+  },
+
+  _setupLogLevelChecker() {
+    const logLevelSource = (
+      process.env.LOG_LEVEL_SOURCE || 'file'
+    ).toLowerCase()
+
+    if (this.logLevelChecker) {
+      this.logLevelChecker.stop()
+      this.logLevelChecker = null
+    }
+
+    if (this.isProduction) {
+      switch (logLevelSource) {
+        case 'file':
+          this.logLevelChecker = new FileLogLevelChecker(
+            this.logger,
+            this.defaultLevel
+          )
+          break
+        case 'gce_metadata':
+          this.logLevelChecker = new GCEMetadataLogLevelChecker(
+            this.logger,
+            this.defaultLevel
+          )
+          break
+        case 'none':
+          break
+        default:
+          // eslint-disable-next-line no-console
+          console.log(`Unrecognised log level source: ${logLevelSource}`)
+      }
+      if (this.logLevelChecker) {
+        this.logLevelChecker.start()
+      }
+    }
+  },
+}
+
+LoggingManager.initialize('default')
+
+function handleWarning(err) {
+  LoggingManager.warn({ err }, 'Warning details')
+}
+
+process.on('warning', handleWarning)
+LoggingManager.removeWarningHandler = () => {
+  process.off('warning', handleWarning)
+}
+
+module.exports = LoggingManager

libraries/logger/package.json

@@ -0,0 +1,39 @@
+{
+  "name": "@overleaf/logger",
+  "homepage": "www.overleaf.com",
+  "description": "A centralised logging system for Overleaf",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/overleaf/overleaf"
+  },
+  "main": "index.js",
+  "license": "AGPL-3.0-only",
+  "version": "3.1.1",
+  "scripts": {
+    "test": "npm run lint && npm run format && npm run types:check && npm run test:unit",
+    "format": "prettier --list-different $PWD/'**/*.{js,cjs,ts}'",
+    "format:fix": "prettier --write $PWD/'**/*.{js,cjs,ts}'",
+    "lint": "eslint --ext .js --ext .cjs --ext .ts --max-warnings 0 --format unix .",
+    "lint:fix": "eslint --fix --ext .js --ext .cjs --ext .ts .",
+    "test:ci": "npm run test:unit",
+    "test:unit": "mocha --exit test/**/*.{js,cjs}",
+    "types:check": "tsc --noEmit"
+  },
+  "dependencies": {
+    "@google-cloud/logging-bunyan": "^5.1.0",
+    "@overleaf/fetch-utils": "*",
+    "@overleaf/o-error": "*",
+    "bunyan": "^1.8.14"
+  },
+  "devDependencies": {
+    "chai": "^4.3.6",
+    "mocha": "^11.1.0",
+    "sandboxed-module": "^2.0.4",
+    "sinon": "^9.2.4",
+    "sinon-chai": "^3.7.0",
+    "typescript": "^5.0.4"
+  },
+  "peerDependencies": {
+    "@overleaf/metrics": "*"
+  }
+}

libraries/logger/serializers.js

@@ -0,0 +1,83 @@
+const OError = require('@overleaf/o-error')
+
+function errSerializer(err) {
+  if (!err) {
+    return err
+  }
+  let message = err.message
+  if (err.path) {
+    // filter paths from the message to avoid duplicate errors with different path in message
+    // (e.g. errors from `fs` methods which have a path attribute)
+    message = message.replace(` '${err.path}'`, '')
+  }
+  return {
+    message,
+    name: err.name,
+    stack: OError.getFullStack(err),
+    info: OError.getFullInfo(err),
+    code: err.code,
+    signal: err.signal,
+    path: err.path,
+  }
+}
+
+function reqSerializer(req) {
+  if (!req) {
+    return req
+  }
+  const headers = req.headers || {}
+  const entry = {
+    method: req.method,
+    url: req.originalUrl || req.url,
+    remoteAddress: getRemoteIp(req),
+    headers: {
+      referer: headers.referer || headers.referrer,
+      'user-agent': headers['user-agent'],
+      'content-length': headers['content-length'],
+    },
+  }
+  if (req.params) {
+    const projectId =
+      req.params.projectId || req.params.project_id || req.params.Project_id
+    const userId = req.params.userId || req.params.user_id
+    const docId = req.params.docId || req.params.doc_id
+    if (projectId) {
+      entry.projectId = projectId
+    }
+    if (userId) {
+      entry.userId = userId
+    }
+    if (docId) {
+      entry.docId = docId
+    }
+  }
+  return entry
+}
+
+function resSerializer(res) {
+  if (!res) {
+    return res
+  }
+  return {
+    statusCode: res.statusCode,
+    headers: {
+      'content-length': res.getHeader && res.getHeader('content-length'),
+    },
+  }
+}
+
+function getRemoteIp(req) {
+  if (req.ip) {
+    return req.ip
+  }
+  if (req.socket) {
+    if (req.socket.socket && req.socket.socket.remoteAddress) {
+      return req.socket.socket.remoteAddress
+    } else if (req.socket.remoteAddress) {
+      return req.socket.remoteAddress
+    }
+  }
+  return null
+}
+
+module.exports = { err: errSerializer, req: reqSerializer, res: resSerializer }

libraries/logger/test/setup.js

@@ -0,0 +1,16 @@
+const chai = require('chai')
+const sinonChai = require('sinon-chai')
+const SandboxedModule = require('sandboxed-module')
+
+// Chai configuration
+chai.should()
+chai.use(sinonChai)
+
+SandboxedModule.configure({
+  globals: { Buffer, JSON, console, process },
+  sourceTransformers: {
+    removeNodePrefix: function (source) {
+      return source.replace(/require\(['"]node:/g, "require('")
+    },
+  },
+})

libraries/logger/test/unit/log-level-checker-tests.js

@@ -0,0 +1,186 @@
+const Path = require('node:path')
+const { promisify } = require('node:util')
+const SandboxedModule = require('sandboxed-module')
+const sinon = require('sinon')
+const { expect } = require('chai')
+
+const MODULE_PATH = Path.join(__dirname, '../../log-level-checker.js')
+const DEFAULT_LEVEL = 'warn'
+const TRACE_LEVEL = 'trace'
+const TRACING_END_TIME_FILE = '/logging/tracingEndTime'
+const NOW = 10000
+const PAST = NOW - 1000
+const FUTURE = NOW + 1000
+
+const delay = promisify(setTimeout)
+
+describe('LogLevelChecker', function () {
+  beforeEach(function () {
+    this.logger = {
+      level: sinon.stub(),
+      fields: { name: 'myapp' },
+    }
+    this.FetchUtils = {
+      fetchString: sinon.stub(),
+    }
+    this.fetchLogLevelEndTimeStub = this.FetchUtils.fetchString.withArgs(
+      'http://metadata.google.internal/computeMetadata/v1/project/attributes/myapp-setLogLevelEndTime',
+      { headers: { 'Metadata-Flavor': 'Google' } }
+    )
+    this.fetchLogLevelEndTimeStub.resolves('')
+
+    this.fs = {
+      promises: {
+        readFile: sinon.stub(),
+      },
+    }
+
+    this.clock = sinon.useFakeTimers(NOW)
+
+    this.module = SandboxedModule.require(MODULE_PATH, {
+      requires: {
+        '@overleaf/fetch-utils': this.FetchUtils,
+        fs: this.fs,
+      },
+    })
+  })
+
+  afterEach(function () {
+    this.clock.restore()
+  })
+
+  describe('FileLogLevelChecker', function () {
+    beforeEach(function () {
+      this.logLevelChecker = new this.module.FileLogLevelChecker(
+        this.logger,
+        DEFAULT_LEVEL
+      )
+    })
+
+    describe('when the file is empty', function () {
+      setupTracingEndTimeFile('')
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+
+    describe("when the file can't be read", function () {
+      beforeEach(async function () {
+        this.fs.promises.readFile.rejects(new Error('Read error!'))
+      })
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+
+    describe('when the file has a timestamp in the future', function () {
+      setupTracingEndTimeFile(FUTURE.toString())
+      checkLogLevel()
+      expectLevelSetTo(TRACE_LEVEL)
+    })
+
+    describe('when the file has a timestamp in the past', function () {
+      setupTracingEndTimeFile(PAST.toString())
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+
+    describe('interval checker', function () {
+      beforeEach(function () {
+        this.fs.promises.readFile.resolves('')
+        this.logLevelChecker.start()
+      })
+
+      afterEach(function () {
+        this.logLevelChecker.stop()
+      })
+
+      it('checks the file every minute', async function () {
+        this.clock.tick(1000)
+        // Yield to the event loop
+        await delay(0)
+        expect(this.logger.level).to.have.been.calledOnceWithExactly(
+          DEFAULT_LEVEL
+        )
+        this.logger.level.reset()
+
+        // Trace until 1.5 minutes in the future
+        const traceUntil = NOW + 90000
+        this.fs.promises.readFile.resolves(traceUntil.toString())
+
+        this.clock.tick(61000)
+        await delay(0)
+        expect(this.logger.level).to.have.been.calledOnceWithExactly(
+          TRACE_LEVEL
+        )
+        this.logger.level.reset()
+
+        this.clock.tick(60000)
+        await delay(0)
+        expect(this.logger.level).to.have.been.calledOnceWithExactly(
+          DEFAULT_LEVEL
+        )
+      })
+    })
+  })
+
+  describe('GCEMetadataLogLevelChecker', function () {
+    beforeEach(function () {
+      this.logLevelChecker = new this.module.GCEMetadataLogLevelChecker(
+        this.logger,
+        DEFAULT_LEVEL
+      )
+    })
+
+    describe('when the response is empty', function () {
+      setupTracingEndTimeGCE('')
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+
+    describe('when the request errors', function () {
+      beforeEach(async function () {
+        this.FetchUtils.fetchString.rejects(new Error('Read error!'))
+      })
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+
+    describe('when the response is a timestamp in the future', function () {
+      setupTracingEndTimeGCE(FUTURE.toString())
+      checkLogLevel()
+      expectLevelSetTo(TRACE_LEVEL)
+    })
+
+    describe('when the response is a timestamp in the past', function () {
+      setupTracingEndTimeGCE(PAST.toString())
+      checkLogLevel()
+      expectLevelSetTo(DEFAULT_LEVEL)
+    })
+  })
+})
+
+function setupTracingEndTimeFile(contents) {
+  beforeEach(`set tracing end time in file to ${contents}`, function () {
+    this.fs.promises.readFile.withArgs(TRACING_END_TIME_FILE).resolves(contents)
+  })
+}
+
+function setupTracingEndTimeGCE(contents) {
+  beforeEach(
+    `set tracing end time in GCE metadata to ${contents}`,
+    function () {
+      this.fetchLogLevelEndTimeStub.resolves(contents)
+    }
+  )
+}
+
+function checkLogLevel() {
+  beforeEach('Check log level', async function () {
+    await this.logLevelChecker.checkLogLevel()
+  })
+}
+
+function expectLevelSetTo(level) {
+  it(`sets the log level to ${level}`, function () {
+    expect(this.logger.level).to.have.been.calledWith(level)
+  })
+}

libraries/logger/test/unit/logging-manager-tests.js

@@ -0,0 +1,202 @@
+const SandboxedModule = require('sandboxed-module')
+const bunyan = require('bunyan')
+const { expect } = require('chai')
+const path = require('node:path')
+const sinon = require('sinon')
+
+const MODULE_PATH = path.join(__dirname, '../../logging-manager.js')
+
+describe('LoggingManager', function () {
+  beforeEach(function () {
+    this.start = Date.now()
+    this.bunyanLogger = {
+      addStream: sinon.stub(),
+      debug: sinon.stub(),
+      error: sinon.stub(),
+      fatal: sinon.stub(),
+      info: sinon.stub(),
+      level: sinon.stub(),
+      warn: sinon.stub(),
+    }
+    this.Bunyan = {
+      createLogger: sinon.stub().returns(this.bunyanLogger),
+      RingBuffer: bunyan.RingBuffer,
+    }
+    this.stackdriverStreamConfig = { stream: 'stackdriver' }
+    this.stackdriverClient = {
+      stream: sinon.stub().returns(this.stackdriverStreamConfig),
+    }
+    this.GCPLogging = {
+      LoggingBunyan: sinon.stub().returns(this.stackdriverClient),
+    }
+    this.FileLogLevelChecker = {
+      start: sinon.stub(),
+      stop: sinon.stub(),
+    }
+    this.GCEMetadataLogLevelChecker = {
+      start: sinon.stub(),
+      stop: sinon.stub(),
+    }
+    this.LogLevelChecker = {
+      FileLogLevelChecker: sinon.stub().returns(this.FileLogLevelChecker),
+      GCEMetadataLogLevelChecker: sinon
+        .stub()
+        .returns(this.GCEMetadataLogLevelChecker),
+    }
+    this.LoggingManager = SandboxedModule.require(MODULE_PATH, {
+      requires: {
+        bunyan: this.Bunyan,
+        './log-level-checker': this.LogLevelChecker,
+      },
+    })
+    this.loggerName = 'test'
+    this.logger = this.LoggingManager.initialize(this.loggerName)
+  })
+
+  afterEach(function () {
+    this.LoggingManager.removeWarningHandler()
+  })
+
+  describe('initialize', function () {
+    beforeEach(function () {
+      this.Bunyan.createLogger.reset()
+    })
+
+    describe('not in production', function () {
+      beforeEach(function () {
+        this.logger = this.LoggingManager.initialize(this.loggerName)
+      })
+
+      it('should default to log level debug', function () {
+        this.Bunyan.createLogger.firstCall.args[0].streams[0].level.should.equal(
+          'debug'
+        )
+      })
+
+      it('should not instantiate a log level checker', function () {
+        expect(this.LoggingManager.logLevelChecker).not.to.exist
+      })
+    })
+
+    describe('in production', function () {
+      beforeEach(function () {
+        process.env.NODE_ENV = 'production'
+        this.logger = this.LoggingManager.initialize(this.loggerName)
+      })
+
+      afterEach(function () {
+        delete process.env.NODE_ENV
+      })
+
+      it('should default to log level info', function () {
+        this.Bunyan.createLogger.firstCall.args[0].streams[0].level.should.equal(
+          'info'
+        )
+      })
+
+      it('should set up a file log level checker', function () {
+        expect(this.logger.logLevelChecker).to.equal(this.FileLogLevelChecker)
+        expect(this.FileLogLevelChecker.start).to.have.been.called
+      })
+    })
+
+    describe('when LOG_LEVEL set in env', function () {
+      beforeEach(function () {
+        process.env.LOG_LEVEL = 'trace'
+        this.LoggingManager.initialize()
+      })
+
+      afterEach(function () {
+        delete process.env.LOG_LEVEL
+      })
+
+      it('should use custom log level', function () {
+        this.Bunyan.createLogger.firstCall.args[0].streams[0].level.should.equal(
+          'trace'
+        )
+      })
+    })
+  })
+
+  describe('bunyan logging', function () {
+    beforeEach(function () {
+      this.logArgs = [{ foo: 'bar' }, 'foo', 'bar']
+    })
+
+    it('should log debug', function () {
+      this.logger.debug(this.logArgs)
+      this.bunyanLogger.debug.should.have.been.calledWith(this.logArgs)
+    })
+
+    it('should log error', function () {
+      this.logger.error(this.logArgs)
+      this.bunyanLogger.error.should.have.been.calledWith(this.logArgs)
+    })
+
+    it('should log fatal', function () {
+      this.logger.fatal(this.logArgs)
+      this.bunyanLogger.fatal.should.have.been.calledWith(this.logArgs)
+    })
+
+    it('should log info', function () {
+      this.logger.info(this.logArgs)
+      this.bunyanLogger.info.should.have.been.calledWith(this.logArgs)
+    })
+
+    it('should log warn', function () {
+      this.logger.warn(this.logArgs)
+      this.bunyanLogger.warn.should.have.been.calledWith(this.logArgs)
+    })
+
+    it('should log err', function () {
+      this.logger.err(this.logArgs)
+      this.bunyanLogger.error.should.have.been.calledWith(this.logArgs)
+    })
+  })
+
+  describe('ringbuffer', function () {
+    beforeEach(function () {
+      this.logBufferMock = [
+        { msg: 'log 1' },
+        { msg: 'log 2' },
+        { level: 50, msg: 'error' },
+      ]
+    })
+
+    describe('when ring buffer size is positive', function () {
+      beforeEach(function () {
+        process.env.LOG_RING_BUFFER_SIZE = '20'
+        this.logger = this.LoggingManager.initialize(this.loggerName)
+        this.logger.ringBuffer.records = this.logBufferMock
+        this.logger.error({}, 'error')
+      })
+
+      afterEach(function () {
+        process.env.LOG_RING_BUFFER_SIZE = undefined
+      })
+
+      it('should include buffered logs in error log and filter out error logs in buffer', function () {
+        this.bunyanLogger.error.lastCall.args[0].logBuffer.should.deep.equal([
+          { msg: 'log 1' },
+          { msg: 'log 2' },
+        ])
+      })
+    })
+
+    describe('when ring buffer size is zero', function () {
+      beforeEach(function () {
+        process.env.LOG_RING_BUFFER_SIZE = '0'
+        this.logger = this.LoggingManager.initialize(this.loggerName)
+        this.logger.error({}, 'error')
+      })
+
+      afterEach(function () {
+        process.env.LOG_RING_BUFFER_SIZE = undefined
+      })
+
+      it('should not include buffered logs in error log', function () {
+        expect(this.bunyanLogger.error.lastCall.args[0].logBuffer).be.undefined
+      })
+    })
+  })
+})

libraries/logger/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.backend.json",
+  "include": [
+    "**/*.js",
+    "**/*.cjs"
+  ]
+}

libraries/metrics/.gitignore

@@ -0,0 +1,3 @@
+node_modules
+
+.npmrc

libraries/metrics/.npmignore

@@ -0,0 +1,4 @@
+/.circleci
+/.eslintrc
+/.nvmrc
+/.prettierrc

libraries/metrics/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/metrics/CHANGELOG.md

@@ -0,0 +1,9 @@
+## v4.1.0
+
+* Allows skipping the `sampleRate` argument.
+
+## v4.0.0
+
+* Send unmodified request and response to logger.
+
+This version of the metrics module only works with versions of the `@overleaf/logger` module greater than v3.0.0

libraries/metrics/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2024 Overleaf
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

libraries/metrics/README.md

@@ -0,0 +1,33 @@
+# overleaf/metrics-module
+
+Wrappers the [prom-client](https://github.com/siimon/prom-client) npm module to provide [Prometheus](https://prometheus.io/) metrics at `/metrics`.
+
+Use:
+
+```
+// Metrics must be initialized before importing anything else
+require('@overleaf/metrics/initialize')
+
+const express = require('express')
+const metrics = require('@overleaf/metrics')
+const app = express()
+metrics.injectMetricsRoute(app)
+```
+
+Request logging can be enabled:
+
+```
+const logger = require('@overleaf/logger')
+...
+app.use(metrics.http.monitor(logger))
+```
+
+The metrics module can be configured through the following environment variables:
+
+- `DEBUG_METRICS` - enables display of debugging messages to the console.
+- `GCP_OPENTELEMETRY` - enables OpenTelemetry tracing for GCP
+- `JAEGER_OPENTELEMETRY` - enables OpenTelemetry tracing for Jaeger (in the dev environment)
+- `METRICS_APP_NAME` - the app label for metrics and spans
+- `METRICS_COMPRESSION_LEVEL` - sets the [compression level](https://www.npmjs.com/package/compression#level) for `/metrics`
+- `STACKDRIVER_LOGGING` - toggles the request logging format
+- `UV_THREADPOOL_SIZE` - sets the libuv [thread pool](http://docs.libuv.org/en/v1.x/threadpool.html) size

libraries/metrics/buildscript.txt

@@ -0,0 +1,10 @@
+metrics
+--dependencies=None
+--docker-repos=gcr.io/overleaf-ops
+--env-add=
+--env-pass-through=
+--esmock-loader=False
+--is-library=True
+--node-version=20.18.2
+--public-repo=False
+--script-version=4.7.0

libraries/metrics/event_loop.js

@@ -0,0 +1,34 @@
+/*
+ * decaffeinate suggestions:
+ * DS102: Remove unnecessary code created because of implicit returns
+ * DS207: Consider shorter variations of null checks
+ * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
+ */
+module.exports = {
+  monitor(logger, interval, logThreshold) {
+    if (interval == null) {
+      interval = 1000
+    }
+    if (logThreshold == null) {
+      logThreshold = 100
+    }
+    const Metrics = require('./index')
+    // check for logger on startup to avoid exceptions later if undefined
+    if (logger == null) {
+      throw new Error('logger is undefined')
+    }
+    // monitor delay in setInterval to detect event loop blocking
+    let previous = Date.now()
+    const intervalId = setInterval(function () {
+      const now = Date.now()
+      const offset = now - previous - interval
+      if (offset > logThreshold) {
+        logger.warn({ offset }, 'slow event loop')
+      }
+      previous = now
+      return Metrics.timing('event-loop-millsec', offset)
+    }, interval)
+
+    return Metrics.registerDestructor(() => clearInterval(intervalId))
+  },
+}

libraries/metrics/http.js

@@ -0,0 +1,78 @@
+const Metrics = require('./index')
+
+function monitor(logger, level = 'debug') {
+  return function (req, res, next) {
+    const startTime = Date.now()
+    req.logger = new RequestLogger(logger, level)
+    const { end } = res
+    res.end = function (...args) {
+      end.apply(this, args)
+      const responseTimeMs = Date.now() - startTime
+      const requestSize = parseInt(req.headers['content-length'], 10)
+      const routePath = getRoutePath(req)
+
+      if (routePath != null) {
+        Metrics.timing('http_request', responseTimeMs, null, {
+          method: req.method,
+          status_code: res.statusCode,
+          path: routePath,
+        })
+        if (requestSize) {
+          Metrics.summary('http_request_size_bytes', requestSize, {
+            method: req.method,
+            status_code: res.statusCode,
+            path: routePath,
+          })
+        }
+      }
+      req.logger.addFields({ responseTimeMs })
+      req.logger.emit(req, res)
+    }
+    next()
+  }
+}
+
+function getRoutePath(req) {
+  if (req.route && req.route.path != null) {
+    return req.route.path
+      .toString()
+      .replace(/\//g, '_')
+      .replace(/:/g, '')
+      .slice(1)
+  }
+  if (req.swagger && req.swagger.apiPath != null) {
+    return req.swagger.apiPath
+  }
+  return null
+}
+
+class RequestLogger {
+  constructor(logger, level) {
+    this._logger = logger
+    this._level = level
+    this._info = {}
+  }
+
+  addFields(fields) {
+    Object.assign(this._info, fields)
+  }
+
+  setLevel(level) {
+    this._level = level
+  }
+
+  disable() {
+    this._disabled = true
+  }
+
+  emit(req, res) {
+    if (this._disabled) {
+      return
+    }
+    this.addFields({ req, res })
+    const url = req.originalUrl || req.url
+    this._logger[this._level](this._info, '%s %s', req.method, url)
+  }
+}
+
+module.exports.monitor = monitor

libraries/metrics/index.js

@@ -0,0 +1,182 @@
+/* eslint-disable no-console */
+
+const ExpressCompression = require('compression')
+const promClient = require('prom-client')
+const promWrapper = require('./prom_wrapper')
+
+const destructors = []
+
+require('./uv_threadpool_size')
+
+function registerDestructor(func) {
+  destructors.push(func)
+}
+
+function injectMetricsRoute(app) {
+  app.get(
+    '/metrics',
+    ExpressCompression({
+      level: parseInt(process.env.METRICS_COMPRESSION_LEVEL || '1', 10),
+    }),
+    function (req, res, next) {
+      res.set('Content-Type', promWrapper.registry.contentType)
+      promWrapper.registry
+        .metrics()
+        .then(metrics => {
+          res.end(metrics)
+        })
+        .catch(err => {
+          next(err)
+        })
+    }
+  )
+}
+
+function buildPromKey(key) {
+  return key.replace(/[^a-zA-Z0-9]/g, '_')
+}
+
+function sanitizeValue(value) {
+  return parseFloat(value)
+}
+
+function set(key, value, sampleRate = 1) {
+  console.log('counts are not currently supported')
+}
+
+function inc(key, sampleRate = 1, labels = {}) {
+  if (arguments.length === 2 && typeof sampleRate === 'object') {
+    labels = sampleRate
+  }
+
+  key = buildPromKey(key)
+  promWrapper.metric('counter', key, labels).inc(labels)
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing inc', key, labels)
+  }
+}
+
+function count(key, count, sampleRate = 1, labels = {}) {
+  if (arguments.length === 3 && typeof sampleRate === 'object') {
+    labels = sampleRate
+  }
+
+  key = buildPromKey(key)
+  promWrapper.metric('counter', key, labels).inc(labels, count)
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing count/inc', key, labels)
+  }
+}
+
+function summary(key, value, labels = {}) {
+  key = buildPromKey(key)
+  promWrapper.metric('summary', key, labels).observe(labels, value)
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing summary', key, value, labels)
+  }
+}
+
+function timing(key, timeSpan, sampleRate = 1, labels = {}) {
+  if (arguments.length === 3 && typeof sampleRate === 'object') {
+    labels = sampleRate
+  }
+
+  key = buildPromKey('timer_' + key)
+  promWrapper.metric('summary', key, labels).observe(labels, timeSpan)
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing timing', key, labels)
+  }
+}
+
+function histogram(key, value, buckets, labels = {}) {
+  key = buildPromKey('histogram_' + key)
+  promWrapper.metric('histogram', key, labels, buckets).observe(labels, value)
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing histogram', key, buckets, labels)
+  }
+}
+
+class Timer {
+  constructor(key, sampleRate = 1, labels = {}, buckets = undefined) {
+    if (typeof sampleRate === 'object') {
+      // called with (key, labels, buckets)
+      if (arguments.length === 3) {
+        buckets = labels
+        labels = sampleRate
+      }
+
+      // called with (key, labels)
+      if (arguments.length === 2) {
+        labels = sampleRate
+      }
+
+      sampleRate = 1 // default value to pass to timing function
+    }
+
+    this.start = new Date()
+    key = buildPromKey(key)
+    this.key = key
+    this.sampleRate = sampleRate
+    this.labels = labels
+    this.buckets = buckets
+  }
+
+  // any labels passed into the done method override labels from constructor
+  done(labels = {}) {
+    const timeSpan = new Date() - this.start
+    if (this.buckets) {
+      histogram(this.key, timeSpan, this.buckets, { ...this.labels, ...labels })
+    } else {
+      timing(this.key, timeSpan, this.sampleRate, { ...this.labels, ...labels })
+    }
+    return timeSpan
+  }
+}
+
+function gauge(key, value, sampleRate = 1, labels = {}) {
+  if (arguments.length === 3 && typeof sampleRate === 'object') {
+    labels = sampleRate
+  }
+
+  key = buildPromKey(key)
+  promWrapper.metric('gauge', key, labels).set(labels, sanitizeValue(value))
+  if (process.env.DEBUG_METRICS) {
+    console.log('doing gauge', key, labels)
+  }
+}
+
+function globalGauge(key, value, sampleRate = 1, labels = {}) {
+  key = buildPromKey(key)
+  labels = { host: 'global', ...labels }
+  promWrapper.metric('gauge', key, labels).set(labels, sanitizeValue(value))
+}
+
+function close() {
+  for (const func of destructors) {
+    func()
+  }
+}
+
+module.exports.registerDestructor = registerDestructor
+module.exports.injectMetricsRoute = injectMetricsRoute
+module.exports.buildPromKey = buildPromKey
+module.exports.sanitizeValue = sanitizeValue
+module.exports.set = set
+module.exports.inc = inc
+module.exports.count = count
+module.exports.summary = summary
+module.exports.timing = timing
+module.exports.histogram = histogram
+module.exports.Timer = Timer
+module.exports.gauge = gauge
+module.exports.globalGauge = globalGauge
+module.exports.close = close
+module.exports.prom = promClient
+module.exports.register = promWrapper.registry
+
+module.exports.http = require('./http')
+module.exports.open_sockets = require('./open_sockets')
+module.exports.leaked_sockets = require('./leaked_sockets')
+module.exports.event_loop = require('./event_loop')
+module.exports.memory = require('./memory')
+module.exports.mongodb = require('./mongodb')

libraries/metrics/initialize.js

@@ -0,0 +1,105 @@
+/* eslint-disable no-console */
+
+/**
+ * This module initializes the metrics module. It should be imported once
+ * before any other module to support code instrumentation.
+ */
+
+const APP_NAME = process.env.METRICS_APP_NAME || 'unknown'
+const BUILD_VERSION = process.env.BUILD_VERSION
+const ENABLE_PROFILE_AGENT = process.env.ENABLE_PROFILE_AGENT === 'true'
+const GCP_OPENTELEMETRY = process.env.GCP_OPENTELEMETRY === 'true'
+const JAEGER_OPENTELEMETRY = process.env.JAEGER_OPENTELEMETRY === 'true'
+
+console.log('Initializing metrics')
+
+if (GCP_OPENTELEMETRY || JAEGER_OPENTELEMETRY) {
+  initializeOpenTelemetryInstrumentation()
+  initializeOpenTelemetryLogging()
+}
+
+if (ENABLE_PROFILE_AGENT) {
+  initializeProfileAgent()
+}
+
+initializePrometheus()
+initializePromWrapper()
+recordProcessStart()
+
+function initializeOpenTelemetryInstrumentation() {
+  console.log('Starting OpenTelemetry instrumentation')
+  const opentelemetry = require('@opentelemetry/sdk-node')
+  const {
+    getNodeAutoInstrumentations,
+  } = require('@opentelemetry/auto-instrumentations-node')
+  const { Resource } = require('@opentelemetry/resources')
+  const {
+    SemanticResourceAttributes,
+  } = require('@opentelemetry/semantic-conventions')
+
+  const resource = new Resource({
+    [SemanticResourceAttributes.SERVICE_NAME]: APP_NAME,
+    [SemanticResourceAttributes.SERVICE_NAMESPACE]: 'Overleaf',
+    'host.type': 'VM',
+  })
+
+  let exporter
+  if (GCP_OPENTELEMETRY) {
+    const GCP = require('@google-cloud/opentelemetry-cloud-trace-exporter')
+    exporter = new GCP.TraceExporter()
+  } else if (JAEGER_OPENTELEMETRY) {
+    const {
+      OTLPTraceExporter,
+    } = require('@opentelemetry/exporter-trace-otlp-http')
+    exporter = new OTLPTraceExporter({
+      url: `http://${process.env.JAEGER_HOST || 'jaeger'}:4318/v1/traces`,
+    })
+  } else {
+    return
+  }
+
+  const sdk = new opentelemetry.NodeSDK({
+    traceExporter: exporter,
+    logger: console,
+    instrumentations: [getNodeAutoInstrumentations()],
+    resource,
+  })
+  sdk.start()
+}
+
+function initializeOpenTelemetryLogging() {
+  const {
+    diag,
+    DiagConsoleLogger,
+    DiagLogLevel,
+  } = require('@opentelemetry/api')
+  diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.INFO)
+}
+
+function initializeProfileAgent() {
+  console.log('Starting Google Profile Agent')
+  const profiler = require('@google-cloud/profiler')
+  profiler.start({
+    serviceContext: {
+      service: APP_NAME,
+      version: BUILD_VERSION,
+    },
+  })
+}
+
+function initializePrometheus() {
+  const os = require('node:os')
+  const promClient = require('prom-client')
+  promClient.register.setDefaultLabels({ app: APP_NAME, host: os.hostname() })
+  promClient.collectDefaultMetrics({ timeout: 5000, prefix: '' })
+}
+
+function initializePromWrapper() {
+  const promWrapper = require('./prom_wrapper')
+  promWrapper.setupSweeping()
+}
+
+function recordProcessStart() {
+  const metrics = require('.')
+  metrics.inc('process_startup')
+}

libraries/metrics/leaked_sockets.js

@@ -0,0 +1,254 @@
+/**
+ * This file monitors HTTP connections in Node.js and logs any potential socket leaks.
+ * It uses the `diagnostics_channel` module to intercept requests and reponses in the
+ * `http` module and tracks the lifetime of each http socket. If a socket is open for
+ * longer than a specified time, it is considered a potential leak and its details are
+ * logged along with the corresponding information from /proc/net/tcp.
+ */
+
+const fs = require('node:fs')
+const diagnosticsChannel = require('node:diagnostics_channel')
+
+const SOCKET_MONITOR_INTERVAL = 60 * 1000
+// set the threshold for logging leaked sockets in minutes, defaults to 15
+const MIN_SOCKET_LEAK_TIME =
+  (parseInt(process.env.LEAKED_SOCKET_AGE_THRESHOLD, 10) || 15) * 60 * 1000
+
+// Record HTTP events using diagnostics_channel
+diagnosticsChannel.subscribe('http.client.request.start', handleRequest)
+diagnosticsChannel.subscribe('http.server.request.start', handleRequest)
+diagnosticsChannel.subscribe('http.client.response.finish', handleResponse)
+diagnosticsChannel.subscribe('http.server.response.finish', handleResponse)
+
+function handleRequest({ request: req }) {
+  const socket = req?.socket
+  if (socket) {
+    recordRequest(req, socket)
+  }
+}
+
+function recordRequest(req, socket) {
+  const { method, protocol, path, url, rawHeaders, _header } = req
+  socket._ol_debug = {
+    method,
+    protocol,
+    url: url ?? path,
+    request: { headers: rawHeaders ?? _header, ts: new Date() },
+  }
+}
+
+function handleResponse({ request: req, response: res }) {
+  const socket = req?.socket || res?.socket
+  if (!socket || !res) {
+    return
+  }
+  if (!socket._ol_debug) {
+    // I don't know if this will ever happen, but if we missed the request,
+    // record it here.
+    recordRequest(req, socket)
+  }
+  const { statusCode, statusMessage, headers, _header } = res
+  Object.assign(socket._ol_debug, {
+    response: {
+      statusCode,
+      statusMessage,
+      headers: headers ?? _header,
+      ts: new Date(),
+    },
+  })
+}
+
+// Additional functions to log request headers with sensitive information redacted
+
+function flattenHeaders(rawHeaders) {
+  // Headers can be an array [KEY, VALUE, KEY, VALUE, ..]
+  // an object {key:value, key:value, ...}
+  // or a string of the headers separated by \r\n
+  // Flatten the array and object headers into the string form.
+  if (Array.isArray(rawHeaders)) {
+    return rawHeaders
+      .map((item, index) => (index % 2 === 0 ? `${item}: ` : `${item}\r\n`))
+      .join('')
+  } else if (typeof rawHeaders === 'object') {
+    return Object.entries(rawHeaders)
+      .map(([key, value]) => `${key}: ${value}\r\n`)
+      .join('')
+  } else if (typeof rawHeaders === 'string') {
+    return rawHeaders
+  } else {
+    return JSON.stringify(rawHeaders)
+  }
+}
+
+const REDACT_REGEX = /^(Authorization|Set-Cookie|Cookie):.*?\r/gim
+
+function redactObject(obj) {
+  const result = {}
+  for (const [key, value] of Object.entries(obj)) {
+    if (value == null) {
+      result[key] = null
+    } else if (key === 'headers') {
+      // remove headers with sensitive information
+      result[key] = flattenHeaders(value).replace(
+        REDACT_REGEX,
+        `$1: REDACTED\r`
+      )
+    } else if (
+      typeof value === 'object' &&
+      ['request', 'response'].includes(key)
+    ) {
+      result[key] = redactObject(value)
+    } else {
+      result[key] = value
+    }
+  }
+  return result
+}
+
+// Check if an old socket has crossed the threshold for logging.
+// We log multiple times with an exponential backoff so we can
+// see how long a socket hangs around.
+
+function isOldSocket(handle) {
+  const now = new Date()
+  const created = handle._ol_debug.request.ts
+  const lastLoggedAt = handle._ol_debug.lastLoggedAt ?? created
+  const nextLogTime = new Date(
+    created.getTime() +
+      Math.max(2 * (lastLoggedAt - created), MIN_SOCKET_LEAK_TIME)
+  )
+  return now >= nextLogTime
+}
+
+function logOldSocket(logger, handle, tcpinfo) {
+  const now = new Date()
+  const info = Object.assign(
+    {
+      localAddress: handle.localAddress,
+      localPort: handle.localPort,
+      remoteAddress: handle.remoteAddress,
+      remotePort: handle.remotePort,
+      tcpinfo,
+      age: Math.floor((now - handle._ol_debug.request.ts) / (60 * 1000)), // age in minutes
+    },
+    redactObject(handle._ol_debug)
+  )
+  handle._ol_debug.lastLoggedAt = now
+  if (tcpinfo) {
+    logger.error(info, 'old socket handle - tcp socket')
+  } else {
+    logger.warn(info, 'stale socket handle - no entry in /proc/net/tcp')
+  }
+}
+
+// Correlate socket handles with /proc/net/tcp entries using a key based on the
+// local and remote addresses and ports. This will allow us to distinguish between
+// sockets that are still open and sockets that have been closed and removed from
+// the /proc/net/tcp table but are still present in the node active handles array.
+
+async function getOpenSockets() {
+  // get open sockets remote and local address:port from /proc/net/tcp
+  const procNetTcp = '/proc/net/tcp'
+  const openSockets = new Map()
+  const lines = await fs.promises.readFile(procNetTcp, 'utf8')
+  for (const line of lines.split('\n')) {
+    const socket = parseProcNetTcp(line)
+    if (socket) {
+      openSockets.set(socket, line)
+    }
+  }
+  return openSockets
+}
+
+function keyFromSocket(socket) {
+  return `${socket.localAddress}:${socket.localPort} -> ${socket.remoteAddress}:${socket.remotePort}`
+}
+
+function decodeHexIpAddress(hex) {
+  // decode hex ip address to dotted decimal notation
+  const ip = parseInt(hex, 16)
+  const a = ip & 0xff
+  const b = (ip >> 8) & 0xff
+  const c = (ip >> 16) & 0xff
+  const d = (ip >> 24) & 0xff
+  return `${a}.${b}.${c}.${d}`
+}
+
+function decodeHexPort(hex) {
+  // decode hex port to decimal
+  return parseInt(hex, 16)
+}
+
+// Regex for extracting the local and remote addresses and ports from the /proc/net/tcp output
+// Example line:
+// 16: AB02A8C0:D9E2 86941864:01BB 01 00000000:00000000 02:000004BE 00000000     0        0 36802 2 0000000000000000 28 4 26 10 -1
+//     ^^^^^^^^^^^^^ ^^^^^^^^^^^^^
+//     local          remote
+
+const TCP_STATE_REGEX =
+  /^\s*\d+:\s+(?<localHexAddress>[0-9A-F]{8}):(?<localHexPort>[0-9A-F]{4})\s+(?<remoteHexAddress>[0-9A-F]{8}):(?<remoteHexPort>[0-9A-F]{4})/i
+
+function parseProcNetTcp(line) {
+  const match = line.match(TCP_STATE_REGEX)
+  if (match) {
+    const { localHexAddress, localHexPort, remoteHexAddress, remoteHexPort } =
+      match.groups
+    return keyFromSocket({
+      localAddress: decodeHexIpAddress(localHexAddress),
+      localPort: decodeHexPort(localHexPort),
+      remoteAddress: decodeHexIpAddress(remoteHexAddress),
+      remotePort: decodeHexPort(remoteHexPort),
+    })
+  }
+}
+
+let LeakedSocketsMonitor
+
+// Export the monitor and scanSockets functions
+
+module.exports = LeakedSocketsMonitor = {
+  monitor(logger) {
+    const interval = setInterval(
+      () => LeakedSocketsMonitor.scanSockets(logger),
+      SOCKET_MONITOR_INTERVAL
+    )
+    const Metrics = require('./index')
+    return Metrics.registerDestructor(() => clearInterval(interval))
+  },
+  scanSockets(logger) {
+    const debugSockets = process._getActiveHandles().filter(handle => {
+      return handle._ol_debug
+    })
+
+    // Bail out if there are no sockets with the _ol_debug property
+    if (debugSockets.length === 0) {
+      return
+    }
+
+    const oldSockets = debugSockets.filter(isOldSocket)
+
+    // Bail out if there are no old sockets to log
+    if (oldSockets.length === 0) {
+      return
+    }
+
+    // If there old sockets to log, get the connections from /proc/net/tcp
+    // to distinguish between sockets that are still open and sockets that
+    // have been closed and removed from the /proc/net/tcp table.
+    getOpenSockets()
+      .then(openSockets => {
+        oldSockets.forEach(handle => {
+          try {
+            const key = keyFromSocket(handle)
+            const tcpinfo = openSockets.get(key)
+            logOldSocket(logger, handle, tcpinfo)
+          } catch (err) {
+            logger.error({ err }, 'error in scanSockets')
+          }
+        })
+      })
+      .catch(err => {
+        logger.error({ err }, 'error getting open sockets')
+      })
+  },
+}

libraries/metrics/memory.js

@@ -0,0 +1,113 @@
+/*
+ * decaffeinate suggestions:
+ * DS102: Remove unnecessary code created because of implicit returns
+ * DS207: Consider shorter variations of null checks
+ * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
+ */
+// record memory usage each minute and run a periodic gc(), keeping cpu
+// usage within allowable range of 1ms per minute. Also, dynamically
+// adjust the period between gc()'s to reach a target of the gc saving
+// 4 megabytes each time.
+
+let MemoryMonitor
+const oneMinute = 60 * 1000
+const oneMegaByte = 1024 * 1024
+
+let CpuTimeBucket = 100 // current cpu time allowance in milliseconds
+const CpuTimeBucketMax = 100 // maximum amount of cpu time allowed in bucket
+const CpuTimeBucketRate = 10 // add this many milliseconds per minute
+
+let gcInterval = 1 // how many minutes between gc (parameter is dynamically adjusted)
+let countSinceLastGc = 0 // how many minutes since last gc
+const MemoryChunkSize = 4 // how many megabytes we need to free to consider gc worth doing
+
+const readyToGc = function () {
+  // update allowed cpu time
+  CpuTimeBucket = CpuTimeBucket + CpuTimeBucketRate
+  CpuTimeBucket =
+    CpuTimeBucket < CpuTimeBucketMax ? CpuTimeBucket : CpuTimeBucketMax
+  // update counts since last gc
+  countSinceLastGc = countSinceLastGc + 1
+  // check there is enough time since last gc and we have enough cpu
+  return countSinceLastGc > gcInterval && CpuTimeBucket > 0
+}
+
+const executeAndTime = function (fn) {
+  // time the execution of fn() and subtract from cpu allowance
+  const t0 = process.hrtime()
+  fn()
+  const dt = process.hrtime(t0)
+  const timeTaken = (dt[0] + dt[1] * 1e-9) * 1e3 // in milliseconds
+  CpuTimeBucket -= Math.ceil(timeTaken)
+  return timeTaken
+}
+
+const inMegaBytes = function (obj) {
+  // convert process.memoryUsage hash {rss,heapTotal,heapFreed} into megabytes
+  const result = {}
+  for (const k in obj) {
+    const v = obj[k]
+    result[k] = (v / oneMegaByte).toFixed(2)
+  }
+  return result
+}
+
+const updateMemoryStats = function (oldMem, newMem) {
+  countSinceLastGc = 0
+  const delta = {}
+  for (const k in newMem) {
+    delta[k] = (newMem[k] - oldMem[k]).toFixed(2)
+  }
+  // take the max of all memory measures
+  const savedMemory = Math.max(-delta.rss, -delta.heapTotal, -delta.heapUsed)
+  delta.megabytesFreed = savedMemory
+  // did it do any good?
+  if (savedMemory < MemoryChunkSize) {
+    gcInterval = gcInterval + 1 // no, so wait longer next time
+  } else {
+    gcInterval = Math.max(gcInterval - 1, 1) // yes, wait less time
+  }
+  return delta
+}
+
+module.exports = MemoryMonitor = {
+  monitor(logger) {
+    const interval = setInterval(() => MemoryMonitor.Check(logger), oneMinute)
+    const Metrics = require('./index')
+    return Metrics.registerDestructor(() => clearInterval(interval))
+  },
+
+  Check(logger) {
+    let mem
+    const Metrics = require('./index')
+    const memBeforeGc = (mem = inMegaBytes(process.memoryUsage()))
+    Metrics.gauge('memory.rss', mem.rss)
+    Metrics.gauge('memory.heaptotal', mem.heapTotal)
+    Metrics.gauge('memory.heapused', mem.heapUsed)
+    Metrics.gauge('memory.gc-interval', gcInterval)
+    // Metrics.gauge("memory.cpu-time-bucket", CpuTimeBucket)
+
+    logger.debug(mem, 'process.memoryUsage()')
+
+    if (global.gc != null && readyToGc()) {
+      const gcTime = executeAndTime(global.gc).toFixed(2)
+      const memAfterGc = inMegaBytes(process.memoryUsage())
+      const deltaMem = updateMemoryStats(memBeforeGc, memAfterGc)
+      logger.debug(
+        {
+          gcTime,
+          memBeforeGc,
+          memAfterGc,
+          deltaMem,
+          gcInterval,
+          CpuTimeBucket,
+        },
+        'global.gc() forced'
+      )
+      // Metrics.timing("memory.gc-time", gcTime)
+      Metrics.gauge('memory.gc-rss-freed', -deltaMem.rss)
+      Metrics.gauge('memory.gc-heaptotal-freed', -deltaMem.heapTotal)
+      return Metrics.gauge('memory.gc-heapused-freed', -deltaMem.heapUsed)
+    }
+  },
+}

libraries/metrics/mongodb.js

@@ -0,0 +1,84 @@
+const { Gauge, Summary } = require('prom-client')
+
+function monitor(mongoClient) {
+  const labelNames = ['mongo_server']
+  const poolSize = new Gauge({
+    name: 'mongo_connection_pool_size',
+    help: 'number of connections in the connection pool',
+    labelNames,
+    // Use this one metric's collect() to set all metrics' values.
+    collect,
+  })
+  const availableConnections = new Gauge({
+    name: 'mongo_connection_pool_available',
+    help: 'number of connections that are not busy',
+    labelNames,
+  })
+  const waitQueueSize = new Gauge({
+    name: 'mongo_connection_pool_waiting',
+    help: 'number of operations waiting for an available connection',
+    labelNames,
+  })
+  const maxPoolSize = new Gauge({
+    name: 'mongo_connection_pool_max',
+    help: 'max size for the connection pool',
+    labelNames,
+  })
+
+  const mongoCommandTimer = new Summary({
+    name: 'mongo_command_time',
+    help: 'time taken to complete a mongo command',
+    percentiles: [],
+    labelNames: ['status', 'method'],
+  })
+
+  if (mongoClient.on) {
+    mongoClient.on('commandSucceeded', event => {
+      mongoCommandTimer.observe(
+        {
+          status: 'success',
+          method: event.commandName === 'find' ? 'read' : 'write',
+        },
+        event.duration
+      )
+    })
+
+    mongoClient.on('commandFailed', event => {
+      mongoCommandTimer.observe(
+        {
+          status: 'failed',
+          method: event.commandName === 'find' ? 'read' : 'write',
+        },
+        event.duration
+      )
+    })
+  }
+
+  function collect() {
+    // Reset all gauges in case they contain values for servers that
+    // disappeared
+    poolSize.reset()
+    availableConnections.reset()
+    waitQueueSize.reset()
+    maxPoolSize.reset()
+
+    const servers = mongoClient.topology?.s?.servers
+    if (servers != null) {
+      for (const [address, server] of servers) {
+        // The server object is different between v4 and v5 (c.f. https://github.com/mongodb/node-mongodb-native/pull/3645)
+        const pool = server.s?.pool || server.pool
+        if (pool == null) {
+          continue
+        }
+
+        const labels = { mongo_server: address }
+        poolSize.set(labels, pool.totalConnectionCount)
+        availableConnections.set(labels, pool.availableConnectionCount)
+        waitQueueSize.set(labels, pool.waitQueueSize)
+        maxPoolSize.set(labels, pool.options.maxPoolSize)
+      }
+    }
+  }
+}
+
+module.exports = { monitor }

libraries/metrics/open_sockets.js

@@ -0,0 +1,99 @@
+/*
+ * decaffeinate suggestions:
+ * DS102: Remove unnecessary code created because of implicit returns
+ * DS205: Consider reworking code to avoid use of IIFEs
+ * DS207: Consider shorter variations of null checks
+ * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
+ */
+let OpenSocketsMonitor
+const seconds = 1000
+
+// In Node 0.10 the default is 5, which means only 5 open connections at one.
+// Node 0.12 has a default of Infinity. Make sure we have no limit set,
+// regardless of Node version.
+require('node:http').globalAgent.maxSockets = Infinity
+require('node:https').globalAgent.maxSockets = Infinity
+
+const SOCKETS_HTTP = require('node:http').globalAgent.sockets
+const SOCKETS_HTTPS = require('node:https').globalAgent.sockets
+const FREE_SOCKETS_HTTP = require('node:http').globalAgent.freeSockets
+const FREE_SOCKETS_HTTPS = require('node:https').globalAgent.freeSockets
+
+// keep track of set gauges and reset them in the next collection cycle
+const SEEN_HOSTS_HTTP = new Set()
+const SEEN_HOSTS_HTTPS = new Set()
+const FREE_SEEN_HOSTS_HTTP = new Set()
+const FREE_SEEN_HOSTS_HTTPS = new Set()
+
+function collectConnectionsCount(
+  sockets,
+  seenHosts,
+  status,
+  https,
+  emitLegacyMetric
+) {
+  const Metrics = require('./index')
+  Object.keys(sockets).forEach(host => seenHosts.add(host))
+  seenHosts.forEach(host => {
+    // host: 'HOST:PORT:'
+    const hostname = host.split(':')[0]
+    const openConnections = (sockets[host] || []).length
+    if (!openConnections) {
+      seenHosts.delete(host)
+    }
+    Metrics.gauge('sockets', openConnections, 1, {
+      path: hostname,
+      method: https,
+      status,
+    })
+    if (status === 'open' && emitLegacyMetric) {
+      // Emit legacy metric to keep old time series intact.
+      Metrics.gauge(
+        `${status}_connections.${https}.${hostname}`,
+        openConnections
+      )
+    }
+  })
+}
+
+module.exports = OpenSocketsMonitor = {
+  monitor(emitLegacyMetric) {
+    const interval = setInterval(
+      () => OpenSocketsMonitor.gaugeOpenSockets(emitLegacyMetric),
+      5 * seconds
+    )
+    const Metrics = require('./index')
+    return Metrics.registerDestructor(() => clearInterval(interval))
+  },
+
+  gaugeOpenSockets(emitLegacyMetric) {
+    collectConnectionsCount(
+      SOCKETS_HTTP,
+      SEEN_HOSTS_HTTP,
+      'open',
+      'http',
+      emitLegacyMetric
+    )
+    collectConnectionsCount(
+      SOCKETS_HTTPS,
+      SEEN_HOSTS_HTTPS,
+      'open',
+      'https',
+      emitLegacyMetric
+    )
+    collectConnectionsCount(
+      FREE_SOCKETS_HTTP,
+      FREE_SEEN_HOSTS_HTTP,
+      'free',
+      'http',
+      false
+    )
+    collectConnectionsCount(
+      FREE_SOCKETS_HTTPS,
+      FREE_SEEN_HOSTS_HTTPS,
+      'free',
+      'https',
+      false
+    )
+  },
+}

libraries/metrics/package.json

@@ -0,0 +1,45 @@
+{
+  "name": "@overleaf/metrics",
+  "version": "4.2.0",
+  "description": "A drop-in metrics and monitoring module for node.js apps",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/overleaf/metrics-module.git"
+  },
+  "main": "index.js",
+  "dependencies": {
+    "@google-cloud/opentelemetry-cloud-trace-exporter": "^2.1.0",
+    "@google-cloud/profiler": "^6.0.0",
+    "@opentelemetry/api": "^1.4.1",
+    "@opentelemetry/auto-instrumentations-node": "^0.39.1",
+    "@opentelemetry/exporter-trace-otlp-http": "^0.41.2",
+    "@opentelemetry/resources": "^1.15.2",
+    "@opentelemetry/sdk-node": "^0.41.2",
+    "@opentelemetry/semantic-conventions": "^1.15.2",
+    "compression": "^1.7.4",
+    "prom-client": "^14.1.1",
+    "yn": "^3.1.1"
+  },
+  "devDependencies": {
+    "bunyan": "^1.0.0",
+    "chai": "^4.3.6",
+    "mocha": "^11.1.0",
+    "sandboxed-module": "^2.0.4",
+    "sinon": "^9.2.4",
+    "typescript": "^5.0.4"
+  },
+  "scripts": {
+    "lint": "eslint --ext .js --ext .cjs --ext .ts --max-warnings 0 --format unix .",
+    "lint:fix": "eslint --fix --ext .js --ext .cjs --ext .ts .",
+    "test:unit": "mocha --exit test/**/*.{js,cjs}",
+    "test:acceptance": "mocha --reporter spec --recursive --exit --grep=$MOCHA_GREP test/acceptance",
+    "test": "npm run lint && npm run format && npm run types:check && npm run test:unit",
+    "format": "prettier --list-different $PWD/'**/*.{js,cjs,ts}'",
+    "format:fix": "prettier --write $PWD/'**/*.{js,cjs,ts}'",
+    "test:ci": "npm run test:unit",
+    "types:check": "tsc --noEmit"
+  },
+  "peerDependencies": {
+    "@overleaf/logger": "*"
+  }
+}

libraries/metrics/prom_wrapper.js

@@ -0,0 +1,177 @@
+const logger = require('@overleaf/logger')
+const prom = require('prom-client')
+const registry = require('prom-client').register
+const metrics = new Map()
+
+const labelsKey = function (labels) {
+  let keys = Object.keys(labels)
+  if (keys.length === 0) {
+    return ''
+  }
+
+  keys = keys.sort()
+
+  let hash = ''
+  for (const key of keys) {
+    if (hash.length) {
+      hash += ','
+    }
+    hash += `${key}:${labels[key]}`
+  }
+
+  return hash
+}
+
+const labelsAsArgs = function (labels, labelNames) {
+  const args = []
+  for (const label of labelNames) {
+    args.push(labels[label] || '')
+  }
+  return args
+}
+
+const PromWrapper = {
+  ttlInMinutes: 0,
+  registry,
+
+  metric(type, name, labels, buckets) {
+    return metrics.get(name) || new MetricWrapper(type, name, labels, buckets)
+  },
+
+  collectDefaultMetrics: prom.collectDefaultMetrics,
+}
+
+class MetricWrapper {
+  constructor(type, name, labels, buckets) {
+    metrics.set(name, this)
+    this.name = name
+    this.instances = new Map()
+    this.lastAccess = new Date()
+
+    const labelNames = labels ? Object.keys(labels) : []
+    switch (type) {
+      case 'counter':
+        this.metric = new prom.Counter({
+          name,
+          help: name,
+          labelNames,
+        })
+        break
+      case 'histogram':
+        this.metric = new prom.Histogram({
+          name,
+          help: name,
+          labelNames,
+          buckets,
+        })
+        break
+      case 'summary':
+        this.metric = new prom.Summary({
+          name,
+          help: name,
+          maxAgeSeconds: 60,
+          ageBuckets: 10,
+          labelNames,
+        })
+        break
+      case 'gauge':
+        this.metric = new prom.Gauge({
+          name,
+          help: name,
+          labelNames,
+        })
+        break
+      default:
+        throw new Error(`Unknown metric type: ${type}`)
+    }
+  }
+
+  inc(labels, value) {
+    this._execMethod('inc', labels, value)
+  }
+
+  observe(labels, value) {
+    this._execMethod('observe', labels, value)
+  }
+
+  set(labels, value) {
+    this._execMethod('set', labels, value)
+  }
+
+  sweep() {
+    const thresh = new Date(Date.now() - 1000 * 60 * PromWrapper.ttlInMinutes)
+    this.instances.forEach((instance, key) => {
+      if (thresh > instance.time) {
+        if (process.env.DEBUG_METRICS) {
+          // eslint-disable-next-line no-console
+          console.log(
+            'Sweeping stale metric instance',
+            this.name,
+            { labels: instance.labels },
+            key
+          )
+        }
+        this.metric.remove(
+          ...labelsAsArgs(instance.labels, this.metric.labelNames)
+        )
+      }
+    })
+
+    if (thresh > this.lastAccess) {
+      if (process.env.DEBUG_METRICS) {
+        // eslint-disable-next-line no-console
+        console.log('Sweeping stale metric', this.name, thresh, this.lastAccess)
+      }
+      metrics.delete(this.name)
+      registry.removeSingleMetric(this.name)
+    }
+  }
+
+  _execMethod(method, labels, value) {
+    const key = labelsKey(labels)
+    if (key !== '') {
+      this.instances.set(key, { time: new Date(), labels })
+    }
+    this.lastAccess = new Date()
+    try {
+      this.metric[method](labels, value)
+    } catch (err) {
+      logger.warn(
+        { err, metric: this.metric.name, labels },
+        'failed to record metric'
+      )
+    }
+  }
+}
+
+let sweepingInterval
+PromWrapper.setupSweeping = function () {
+  if (sweepingInterval) {
+    clearInterval(sweepingInterval)
+  }
+  if (!PromWrapper.ttlInMinutes) {
+    if (process.env.DEBUG_METRICS) {
+      // eslint-disable-next-line no-console
+      console.log('Not registering sweep method -- empty ttl')
+    }
+    return
+  }
+  if (process.env.DEBUG_METRICS) {
+    // eslint-disable-next-line no-console
+    console.log('Registering sweep method')
+  }
+  sweepingInterval = setInterval(function () {
+    if (process.env.DEBUG_METRICS) {
+      // eslint-disable-next-line no-console
+      console.log('Sweeping metrics')
+    }
+    metrics.forEach((metric, key) => {
+      metric.sweep()
+    })
+  }, 60000)
+
+  const Metrics = require('./index')
+  Metrics.registerDestructor(() => clearInterval(sweepingInterval))
+}
+
+module.exports = PromWrapper

libraries/metrics/test/acceptance/metrics_tests.js

@@ -0,0 +1,343 @@
+const { promisify } = require('node:util')
+const os = require('node:os')
+const http = require('node:http')
+const { expect } = require('chai')
+const Metrics = require('../..')
+
+const HOSTNAME = os.hostname()
+const APP_NAME = 'test-app'
+const sleep = promisify(setTimeout)
+
+describe('Metrics module', function () {
+  before(function () {
+    process.env.METRICS_APP_NAME = 'test-app'
+    require('../../initialize')
+  })
+
+  describe('at startup', function () {
+    it('increments the process_startup counter', async function () {
+      await expectMetricValue('process_startup', 1)
+    })
+
+    it('collects default metrics', async function () {
+      const metric = await getMetric('process_cpu_user_seconds_total')
+      expect(metric).to.exist
+    })
+  })
+
+  describe('inc()', function () {
+    it('increments counts by 1', async function () {
+      Metrics.inc('duck_count')
+      await expectMetricValue('duck_count', 1)
+      Metrics.inc('duck_count')
+      Metrics.inc('duck_count')
+      await expectMetricValue('duck_count', 3)
+    })
+
+    it('escapes special characters in the key', async function () {
+      Metrics.inc('show.me the $!!')
+      await expectMetricValue('show_me_the____', 1)
+    })
+  })
+
+  describe('count()', function () {
+    it('increments counts by the given count', async function () {
+      Metrics.count('rabbit_count', 5)
+      await expectMetricValue('rabbit_count', 5)
+      Metrics.count('rabbit_count', 6)
+      Metrics.count('rabbit_count', 7)
+      await expectMetricValue('rabbit_count', 18)
+    })
+  })
+
+  describe('summary()', function () {
+    it('collects observations', async function () {
+      Metrics.summary('oven_temp', 200)
+      Metrics.summary('oven_temp', 300)
+      Metrics.summary('oven_temp', 450)
+      const sum = await getSummarySum('oven_temp')
+      expect(sum).to.equal(950)
+    })
+  })
+
+  describe('timing()', function () {
+    it('collects timings', async function () {
+      Metrics.timing('sprint_100m', 10)
+      Metrics.timing('sprint_100m', 20)
+      Metrics.timing('sprint_100m', 30)
+      const sum = await getSummarySum('timer_sprint_100m')
+      expect(sum).to.equal(60)
+    })
+  })
+
+  describe('histogram()', function () {
+    it('collects in buckets', async function () {
+      const buckets = [10, 100, 1000]
+      Metrics.histogram('distance', 10, buckets)
+      Metrics.histogram('distance', 20, buckets)
+      Metrics.histogram('distance', 100, buckets)
+      Metrics.histogram('distance', 200, buckets)
+      Metrics.histogram('distance', 1000, buckets)
+      Metrics.histogram('distance', 2000, buckets)
+      const sum = await getSummarySum('histogram_distance')
+      expect(sum).to.equal(3330)
+      await checkHistogramValues('histogram_distance', {
+        10: 1,
+        100: 3,
+        1000: 5,
+        '+Inf': 6,
+      })
+    })
+  })
+
+  describe('Timer', function () {
+    beforeEach('collect timings', async function () {
+      const buckets = [10, 100, 1000]
+      for (const duration of [1, 1, 1, 15, 15, 15, 105, 105, 105]) {
+        const withBuckets = new Metrics.Timer(
+          'height',
+          1,
+          { label_1: 'a' },
+          buckets
+        )
+        const withOutBuckets = new Metrics.Timer('depth', 1, { label_2: 'b' })
+        await sleep(duration)
+        withBuckets.done()
+        withOutBuckets.done({ label_3: 'c' })
+      }
+    })
+
+    it('with buckets', async function () {
+      await checkHistogramValues('histogram_height', {
+        10: 3,
+        100: 6,
+        1000: 9,
+        '+Inf': 9,
+      })
+      const labelNames = await getMetric('histogram_height').labelNames
+      expect(labelNames).to.deep.equal(['label_1'])
+    })
+
+    it('without buckets', async function () {
+      await checkSummaryValues('timer_depth', {
+        0.01: 1,
+        0.05: 1,
+        0.5: 15,
+        0.9: 105,
+        0.95: 105,
+        0.99: 105,
+        0.999: 105,
+      })
+      const labelNames = await getMetric('timer_depth').labelNames
+      expect(labelNames).to.deep.equal(['label_2', 'label_3'])
+    })
+  })
+
+  describe('gauge()', function () {
+    it('records values', async function () {
+      Metrics.gauge('water_level', 1.5)
+      await expectMetricValue('water_level', 1.5)
+      Metrics.gauge('water_level', 4.2)
+      await expectMetricValue('water_level', 4.2)
+    })
+  })
+
+  describe('globalGauge()', function () {
+    it('records values without a host label', async function () {
+      Metrics.globalGauge('tire_pressure', 99.99)
+      const { value, labels } = await getMetricValue('tire_pressure')
+      expect(value).to.equal(99.99)
+      expect(labels.host).to.equal('global')
+      expect(labels.app).to.equal(APP_NAME)
+    })
+  })
+
+  describe('open_sockets', function () {
+    const keyServer1 = 'open_connections_http_127_42_42_1'
+    const keyServer2 = 'open_connections_http_127_42_42_2'
+
+    let finish1, finish2, emitResponse1, emitResponse2
+    function resetEmitResponse1() {
+      emitResponse1 = new Promise(resolve => (finish1 = resolve))
+    }
+    resetEmitResponse1()
+    function resetEmitResponse2() {
+      emitResponse2 = new Promise(resolve => (finish2 = resolve))
+    }
+    resetEmitResponse2()
+
+    let server1, server2
+    before(function setupServer1(done) {
+      server1 = http.createServer((req, res) => {
+        res.write('...')
+        emitResponse1.then(() => res.end())
+      })
+      server1.listen(0, '127.42.42.1', done)
+    })
+    before(function setupServer2(done) {
+      server2 = http.createServer((req, res) => {
+        res.write('...')
+        emitResponse2.then(() => res.end())
+      })
+      server2.listen(0, '127.42.42.2', done)
+    })
+    after(function cleanupPendingRequests() {
+      finish1()
+      finish2()
+    })
+    after(function shutdownServer1(done) {
+      if (server1) server1.close(done)
+    })
+    after(function shutdownServer2(done) {
+      if (server2) server2.close(done)
+    })
+
+    let urlServer1, urlServer2
+    before(function setUrls() {
+      urlServer1 = `http://127.42.42.1:${server1.address().port}/`
+      urlServer2 = `http://127.42.42.2:${server2.address().port}/`
+    })
+    describe('gaugeOpenSockets()', function () {
+      beforeEach(function runGaugeOpenSockets() {
+        Metrics.open_sockets.gaugeOpenSockets(true)
+      })
+
+      describe('without pending connections', function () {
+        it('emits no open_connections', async function () {
+          await expectNoMetricValue(keyServer1)
+          await expectNoMetricValue(keyServer2)
+        })
+      })
+
+      describe('with pending connections for server1', function () {
+        before(function (done) {
+          http.get(urlServer1)
+          http.get(urlServer1)
+          setTimeout(done, 10)
+        })
+
+        it('emits 2 open_connections for server1', async function () {
+          await expectMetricValue(keyServer1, 2)
+        })
+
+        it('emits no open_connections for server2', async function () {
+          await expectNoMetricValue(keyServer2)
+        })
+      })
+
+      describe('with pending connections for server1 and server2', function () {
+        before(function (done) {
+          http.get(urlServer2)
+          http.get(urlServer2)
+          setTimeout(done, 10)
+        })
+
+        it('emits 2 open_connections for server1', async function () {
+          await expectMetricValue(keyServer1, 2)
+        })
+
+        it('emits 2 open_connections for server2', async function () {
+          await expectMetricValue(keyServer2, 2)
+        })
+      })
+
+      describe('when requests finish for server1', function () {
+        before(function (done) {
+          finish1()
+          resetEmitResponse1()
+          http.get(urlServer1)
+
+          setTimeout(done, 10)
+        })
+
+        it('emits 1 open_connections for server1', async function () {
+          await expectMetricValue(keyServer1, 1)
+        })
+
+        it('emits 2 open_connections for server2', async function () {
+          await expectMetricValue(keyServer2, 2)
+        })
+      })
+
+      describe('when all requests complete', function () {
+        before(function (done) {
+          finish1()
+          finish2()
+
+          setTimeout(done, 10)
+        })
+
+        it('emits no open_connections', async function () {
+          await expectNoMetricValue(keyServer1)
+          await expectNoMetricValue(keyServer2)
+        })
+      })
+    })
+  })
+})
+
+function getMetric(key) {
+  return Metrics.register.getSingleMetric(key)
+}
+
+async function getSummarySum(key) {
+  const metric = getMetric(key)
+  const item = await metric.get()
+  for (const value of item.values) {
+    if (value.metricName === `${key}_sum`) {
+      return value.value
+    }
+  }
+  return null
+}
+
+async function checkHistogramValues(key, values) {
+  const metric = getMetric(key)
+  const item = await metric.get()
+  const found = {}
+  for (const value of item.values) {
+    const bucket = value.labels.le
+    if (!bucket) continue
+    found[bucket] = value.value
+  }
+  expect(found).to.deep.equal(values)
+  return null
+}
+
+async function checkSummaryValues(key, values) {
+  const metric = getMetric(key)
+  const item = await metric.get()
+  const found = {}
+  for (const value of item.values) {
+    const quantile = value.labels.quantile
+    if (!quantile) continue
+    found[quantile] = value.value
+  }
+  for (const quantile of Object.keys(values)) {
+    expect(found[quantile]).to.be.within(
+      values[quantile] - 5,
+      values[quantile] + 15,
+      `quantile: ${quantile}`
+    )
+  }
+  return null
+}
+
+async function getMetricValue(key) {
+  const metrics = await Metrics.register.getMetricsAsJSON()
+  const metric = metrics.find(m => m.name === key)
+  return metric.values[0]
+}
+
+async function expectMetricValue(key, expectedValue) {
+  const value = await getMetricValue(key)
+  expect(value.value).to.equal(expectedValue)
+  expect(value.labels.host).to.equal(HOSTNAME)
+  expect(value.labels.app).to.equal(APP_NAME)
+}
+
+async function expectNoMetricValue(key) {
+  const metric = getMetric(key)
+  if (!metric) return
+  await expectMetricValue(key, 0)
+}

libraries/metrics/test/unit/js/event_loop.js

@@ -0,0 +1,44 @@
+/*
+ * decaffeinate suggestions:
+ * DS102: Remove unnecessary code created because of implicit returns
+ * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
+ */
+const chai = require('chai')
+const { expect } = chai
+const path = require('node:path')
+const modulePath = path.join(__dirname, '../../../event_loop.js')
+const SandboxedModule = require('sandboxed-module')
+const sinon = require('sinon')
+
+describe('event_loop', function () {
+  before(function () {
+    this.metrics = {
+      timing: sinon.stub(),
+      registerDestructor: sinon.stub(),
+    }
+    this.logger = {
+      warn: sinon.stub(),
+    }
+    return (this.event_loop = SandboxedModule.require(modulePath, {
+      requires: {
+        './index': this.metrics,
+      },
+    }))
+  })
+
+  describe('with a logger provided', function () {
+    before(function () {
+      return this.event_loop.monitor(this.logger)
+    })
+
+    return it('should register a destructor with metrics', function () {
+      return expect(this.metrics.registerDestructor.called).to.equal(true)
+    })
+  })
+
+  return describe('without a logger provided', function () {
+    return it('should throw an exception', function () {
+      return expect(this.event_loop.monitor).to.throw('logger is undefined')
+    })
+  })
+})

libraries/metrics/test/unit/js/http.js

@@ -0,0 +1,171 @@
+const Path = require('node:path')
+const SandboxedModule = require('sandboxed-module')
+const sinon = require('sinon')
+
+const MODULE_PATH = Path.join(__dirname, '../../../http.js')
+
+describe('http.monitor', function () {
+  beforeEach(function () {
+    this.req = {
+      method: 'POST',
+      url: '/project/1234/cleanup',
+      headers: {
+        'content-length': '123',
+      },
+      route: {
+        path: '/project/:id/cleanup',
+      },
+    }
+    this.originalResponseEnd = sinon.stub()
+    this.res = {
+      end: this.originalResponseEnd,
+    }
+    this.data = 'data'
+    this.logger = {
+      debug: sinon.stub(),
+      info: sinon.stub(),
+      warn: sinon.stub(),
+    }
+    this.Metrics = {
+      timing: sinon.stub(),
+      summary: sinon.stub(),
+    }
+    this.clock = sinon.useFakeTimers()
+
+    this.http = SandboxedModule.require(MODULE_PATH, {
+      requires: {
+        './index': this.Metrics,
+      },
+    })
+  })
+
+  afterEach(function () {
+    this.clock.restore()
+  })
+
+  describe('with the default options', function () {
+    beforeEach('set up the monitor', function (done) {
+      this.http.monitor(this.logger)(this.req, this.res, done)
+    })
+
+    describe('after a simple request', function () {
+      endRequest()
+      expectOriginalEndCalled()
+      expectMetrics()
+
+      it('logs the request at the DEBUG level', function () {
+        sinon.assert.calledWith(
+          this.logger.debug,
+          { req: this.req, res: this.res, responseTimeMs: 500 },
+          '%s %s',
+          this.req.method,
+          this.req.url
+        )
+      })
+    })
+
+    describe('when logging is disabled', function () {
+      beforeEach('disable logging', function () {
+        this.req.logger.disable()
+      })
+
+      endRequest()
+      expectOriginalEndCalled()
+      expectMetrics()
+
+      it("doesn't log the request", function () {
+        sinon.assert.notCalled(this.logger.debug)
+      })
+    })
+
+    describe('with custom log fields', function () {
+      beforeEach('add custom fields', function () {
+        this.req.logger.addFields({ a: 1, b: 2 })
+      })
+
+      endRequest()
+
+      it('logs the request with the custom log fields', function () {
+        sinon.assert.calledWith(
+          this.logger.debug,
+          { req: this.req, res: this.res, responseTimeMs: 500, a: 1, b: 2 },
+          '%s %s',
+          this.req.method,
+          this.req.url
+        )
+      })
+    })
+
+    describe('when setting the log level', function () {
+      beforeEach('set custom level', function () {
+        this.req.logger.setLevel('warn')
+      })
+
+      endRequest()
+
+      it('logs the request at the custom level', function () {
+        sinon.assert.calledWith(
+          this.logger.warn,
+          { req: this.req, res: this.res, responseTimeMs: 500 },
+          '%s %s',
+          this.req.method,
+          this.req.url
+        )
+      })
+    })
+  })
+
+  describe('with a different default log level', function () {
+    beforeEach('set up the monitor', function (done) {
+      this.http.monitor(this.logger, 'info')(this.req, this.res, done)
+    })
+
+    endRequest()
+
+    it('logs the request at that level', function () {
+      sinon.assert.calledWith(
+        this.logger.info,
+        { req: this.req, res: this.res, responseTimeMs: 500 },
+        '%s %s',
+        this.req.method,
+        this.req.url
+      )
+    })
+  })
+})
+
+function endRequest() {
+  beforeEach('end the request', function () {
+    this.clock.tick(500)
+    this.res.end(this.data)
+  })
+}
+
+function expectOriginalEndCalled() {
+  it('calls the original res.end()', function () {
+    sinon.assert.calledWith(this.originalResponseEnd, this.data)
+  })
+}
+
+function expectMetrics() {
+  it('records the response time', function () {
+    sinon.assert.calledWith(this.Metrics.timing, 'http_request', 500, null, {
+      method: this.req.method,
+      status_code: this.res.status_code,
+      path: 'project_id_cleanup',
+    })
+  })
+
+  it('records the request size', function () {
+    sinon.assert.calledWith(
+      this.Metrics.summary,
+      'http_request_size_bytes',
+      123,
+      {
+        method: this.req.method,
+        status_code: this.res.status_code,
+        path: 'project_id_cleanup',
+      }
+    )
+  })
+}

libraries/metrics/test/unit/js/mongodb.js

@@ -0,0 +1,89 @@
+const Metrics = require('../../..')
+
+const { expect } = require('chai')
+const prom = require('prom-client')
+
+describe('mongodb', function () {
+  beforeEach(function () {
+    prom.register.clear()
+    this.pool = {
+      totalConnectionCount: 8,
+      availableConnectionCount: 2,
+      waitQueueSize: 4,
+      options: { maxPoolSize: 10 },
+    }
+    this.servers = new Map([['server1', { s: { pool: this.pool } }]])
+
+    this.mongoClient = { topology: { s: { servers: this.servers } } }
+  })
+
+  it('handles an unconnected client', async function () {
+    const mongoClient = {}
+    Metrics.mongodb.monitor(mongoClient)
+    const metrics = await getMetrics()
+    expect(metrics).to.deep.equal({})
+  })
+
+  it('collects Mongo metrics', async function () {
+    Metrics.mongodb.monitor(this.mongoClient)
+    const metrics = await getMetrics()
+    expect(metrics).to.deep.equal({
+      'mongo_connection_pool_max:server1': 10,
+      'mongo_connection_pool_size:server1': 8,
+      'mongo_connection_pool_available:server1': 2,
+      'mongo_connection_pool_waiting:server1': 4,
+    })
+  })
+
+  it('handles topology changes', async function () {
+    Metrics.mongodb.monitor(this.mongoClient)
+    let metrics = await getMetrics()
+    expect(metrics).to.deep.equal({
+      'mongo_connection_pool_max:server1': 10,
+      'mongo_connection_pool_size:server1': 8,
+      'mongo_connection_pool_available:server1': 2,
+      'mongo_connection_pool_waiting:server1': 4,
+    })
+
+    // Add a server
+    this.servers.set('server2', this.servers.get('server1'))
+    metrics = await getMetrics()
+    expect(metrics).to.deep.equal({
+      'mongo_connection_pool_max:server1': 10,
+      'mongo_connection_pool_size:server1': 8,
+      'mongo_connection_pool_available:server1': 2,
+      'mongo_connection_pool_waiting:server1': 4,
+      'mongo_connection_pool_max:server2': 10,
+      'mongo_connection_pool_size:server2': 8,
+      'mongo_connection_pool_available:server2': 2,
+      'mongo_connection_pool_waiting:server2': 4,
+    })
+
+    // Delete a server
+    this.servers.delete('server1')
+    metrics = await getMetrics()
+    expect(metrics).to.deep.equal({
+      'mongo_connection_pool_max:server2': 10,
+      'mongo_connection_pool_size:server2': 8,
+      'mongo_connection_pool_available:server2': 2,
+      'mongo_connection_pool_waiting:server2': 4,
+    })
+
+    // Delete another server
+    this.servers.delete('server2')
+    metrics = await getMetrics()
+    expect(metrics).to.deep.equal({})
+  })
+})
+
+async function getMetrics() {
+  const metrics = await prom.register.getMetricsAsJSON()
+  const result = {}
+  for (const metric of metrics) {
+    for (const value of metric.values) {
+      const key = `${metric.name}:${value.labels.mongo_server}`
+      result[key] = value.value
+    }
+  }
+  return result
+}

libraries/metrics/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.backend.json",
+  "include": [
+    "**/*.js",
+    "**/*.cjs"
+  ]
+}

libraries/metrics/uv_threadpool_size.js

@@ -0,0 +1,5 @@
+if (!process.env.UV_THREADPOOL_SIZE) {
+  process.env.UV_THREADPOOL_SIZE = 16
+  // eslint-disable-next-line no-console
+  console.log(`Set UV_THREADPOOL_SIZE=${process.env.UV_THREADPOOL_SIZE}`)
+}

libraries/mongo-utils/.gitignore

@@ -0,0 +1,3 @@
+
+# managed by monorepo$ bin/update_build_scripts
+.npmrc

libraries/mongo-utils/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/mongo-utils/batchedUpdate.js

@@ -0,0 +1,317 @@
+// @ts-check
+/* eslint-disable no-console */
+const { ObjectId, ReadPreference } = require('mongodb')
+
+const READ_PREFERENCE_SECONDARY =
+  process.env.MONGO_HAS_SECONDARIES === 'true'
+    ? ReadPreference.secondary.mode
+    : ReadPreference.secondaryPreferred.mode
+
+const ONE_MONTH_IN_MS = 1000 * 60 * 60 * 24 * 31
+let ID_EDGE_PAST
+const ID_EDGE_FUTURE = objectIdFromMs(Date.now() + 1000)
+let BATCH_DESCENDING
+let BATCH_SIZE
+let VERBOSE_LOGGING
+let BATCH_RANGE_START
+let BATCH_RANGE_END
+let BATCH_MAX_TIME_SPAN_IN_MS
+let BATCHED_UPDATE_RUNNING = false
+
+/**
+ * @typedef {import("mongodb").Collection} Collection
+ * @typedef {import("mongodb-legacy").Collection} LegacyCollection
+ * @typedef {import("mongodb").Document} Document
+ * @typedef {import("mongodb").FindOptions} FindOptions
+ * @typedef {import("mongodb").UpdateFilter<Document>} UpdateDocument
+ */
+
+/**
+ * @typedef {Object} BatchedUpdateOptions
+ * @property {string} [BATCH_DESCENDING]
+ * @property {string} [BATCH_LAST_ID]
+ * @property {string} [BATCH_MAX_TIME_SPAN_IN_MS]
+ * @property {string} [BATCH_RANGE_END]
+ * @property {string} [BATCH_RANGE_START]
+ * @property {string} [BATCH_SIZE]
+ * @property {string} [VERBOSE_LOGGING]
+ */
+
+/**
+ * @param {BatchedUpdateOptions} options
+ */
+function refreshGlobalOptionsForBatchedUpdate(options = {}) {
+  options = Object.assign({}, options, process.env)
+
+  BATCH_DESCENDING = options.BATCH_DESCENDING === 'true'
+  BATCH_SIZE = parseInt(options.BATCH_SIZE || '1000', 10) || 1000
+  VERBOSE_LOGGING = options.VERBOSE_LOGGING === 'true'
+  if (options.BATCH_LAST_ID) {
+    BATCH_RANGE_START = objectIdFromInput(options.BATCH_LAST_ID)
+  } else if (options.BATCH_RANGE_START) {
+    BATCH_RANGE_START = objectIdFromInput(options.BATCH_RANGE_START)
+  } else {
+    if (BATCH_DESCENDING) {
+      BATCH_RANGE_START = ID_EDGE_FUTURE
+    } else {
+      BATCH_RANGE_START = ID_EDGE_PAST
+    }
+  }
+  BATCH_MAX_TIME_SPAN_IN_MS = parseInt(
+    options.BATCH_MAX_TIME_SPAN_IN_MS || ONE_MONTH_IN_MS.toString(),
+    10
+  )
+  if (options.BATCH_RANGE_END) {
+    BATCH_RANGE_END = objectIdFromInput(options.BATCH_RANGE_END)
+  } else {
+    if (BATCH_DESCENDING) {
+      BATCH_RANGE_END = ID_EDGE_PAST
+    } else {
+      BATCH_RANGE_END = ID_EDGE_FUTURE
+    }
+  }
+}
+
+/**
+ * @param {Collection | LegacyCollection} collection
+ * @param {Document} query
+ * @param {ObjectId} start
+ * @param {ObjectId} end
+ * @param {Document} projection
+ * @param {FindOptions} findOptions
+ * @return {Promise<Array<Document>>}
+ */
+async function getNextBatch(
+  collection,
+  query,
+  start,
+  end,
+  projection,
+  findOptions
+) {
+  if (BATCH_DESCENDING) {
+    query._id = {
+      $gt: end,
+      $lte: start,
+    }
+  } else {
+    query._id = {
+      $gt: start,
+      $lte: end,
+    }
+  }
+  return await collection
+    .find(query, findOptions)
+    .project(projection)
+    .sort({ _id: BATCH_DESCENDING ? -1 : 1 })
+    .limit(BATCH_SIZE)
+    .toArray()
+}
+
+/**
+ * @param {Collection | LegacyCollection} collection
+ * @param {Array<Document>} nextBatch
+ * @param {UpdateDocument} update
+ * @return {Promise<void>}
+ */
+async function performUpdate(collection, nextBatch, update) {
+  await collection.updateMany(
+    { _id: { $in: nextBatch.map(entry => entry._id) } },
+    update
+  )
+}
+
+/**
+ * @param {string} input
+ * @return {ObjectId}
+ */
+function objectIdFromInput(input) {
+  if (input.includes('T')) {
+    const t = new Date(input).getTime()
+    if (Number.isNaN(t)) throw new Error(`${input} is not a valid date`)
+    return objectIdFromMs(t)
+  } else {
+    return new ObjectId(input)
+  }
+}
+
+/**
+ * @param {ObjectId} objectId
+ * @return {string}
+ */
+function renderObjectId(objectId) {
+  return `${objectId} (${objectId.getTimestamp().toISOString()})`
+}
+
+/**
+ * @param {number} ms
+ * @return {ObjectId}
+ */
+function objectIdFromMs(ms) {
+  return ObjectId.createFromTime(ms / 1000)
+}
+
+/**
+ * @param {ObjectId} id
+ * @return {number}
+ */
+function getMsFromObjectId(id) {
+  return id.getTimestamp().getTime()
+}
+
+/**
+ * @param {ObjectId} start
+ * @return {ObjectId}
+ */
+function getNextEnd(start) {
+  let end
+  if (BATCH_DESCENDING) {
+    end = objectIdFromMs(getMsFromObjectId(start) - BATCH_MAX_TIME_SPAN_IN_MS)
+    if (getMsFromObjectId(end) <= getMsFromObjectId(BATCH_RANGE_END)) {
+      end = BATCH_RANGE_END
+    }
+  } else {
+    end = objectIdFromMs(getMsFromObjectId(start) + BATCH_MAX_TIME_SPAN_IN_MS)
+    if (getMsFromObjectId(end) >= getMsFromObjectId(BATCH_RANGE_END)) {
+      end = BATCH_RANGE_END
+    }
+  }
+  return end
+}
+
+/**
+ * @param {Collection | LegacyCollection} collection
+ * @return {Promise<ObjectId|null>}
+ */
+async function getIdEdgePast(collection) {
+  const [first] = await collection
+    .find({})
+    .project({ _id: 1 })
+    .sort({ _id: 1 })
+    .limit(1)
+    .toArray()
+  if (!first) return null
+  // Go one second further into the past in order to include the first entry via
+  // first._id > ID_EDGE_PAST
+  return objectIdFromMs(Math.max(0, getMsFromObjectId(first._id) - 1000))
+}
+
+/**
+ * @param {Collection | LegacyCollection} collection
+ * @param {Document} query
+ * @param {UpdateDocument | ((batch: Array<Document>) => Promise<void>)} update
+ * @param {Document} [projection]
+ * @param {FindOptions} [findOptions]
+ * @param {BatchedUpdateOptions} [batchedUpdateOptions]
+ */
+async function batchedUpdate(
+  collection,
+  query,
+  update,
+  projection,
+  findOptions,
+  batchedUpdateOptions
+) {
+  // only a single batchedUpdate can run at a time due to global variables
+  if (BATCHED_UPDATE_RUNNING) {
+    throw new Error('batchedUpdate is already running')
+  }
+  try {
+    BATCHED_UPDATE_RUNNING = true
+    ID_EDGE_PAST = await getIdEdgePast(collection)
+    if (!ID_EDGE_PAST) {
+      console.warn(
+        `The collection ${collection.collectionName} appears to be empty.`
+      )
+      return 0
+    }
+    refreshGlobalOptionsForBatchedUpdate(batchedUpdateOptions)
+
+    findOptions = findOptions || {}
+    findOptions.readPreference = READ_PREFERENCE_SECONDARY
+
+    projection = projection || { _id: 1 }
+    let nextBatch
+    let updated = 0
+    let start = BATCH_RANGE_START
+
+    while (start !== BATCH_RANGE_END) {
+      let end = getNextEnd(start)
+      nextBatch = await getNextBatch(
+        collection,
+        query,
+        start,
+        end,
+        projection,
+        findOptions
+      )
+      if (nextBatch.length > 0) {
+        end = nextBatch[nextBatch.length - 1]._id
+        updated += nextBatch.length
+
+        if (VERBOSE_LOGGING) {
+          console.log(
+            `Running update on batch with ids ${JSON.stringify(
+              nextBatch.map(entry => entry._id)
+            )}`
+          )
+        } else {
+          console.error(`Running update on batch ending ${renderObjectId(end)}`)
+        }
+
+        if (typeof update === 'function') {
+          await update(nextBatch)
+        } else {
+          await performUpdate(collection, nextBatch, update)
+        }
+      }
+      console.error(`Completed batch ending ${renderObjectId(end)}`)
+      start = end
+    }
+    return updated
+  } finally {
+    BATCHED_UPDATE_RUNNING = false
+  }
+}
+
+/**
+ * @param {Collection | LegacyCollection} collection
+ * @param {Document} query
+ * @param {UpdateDocument | ((batch: Array<Object>) => Promise<void>)} update
+ * @param {Document} [projection]
+ * @param {FindOptions} [findOptions]
+ * @param {BatchedUpdateOptions} [batchedUpdateOptions]
+ */
+function batchedUpdateWithResultHandling(
+  collection,
+  query,
+  update,
+  projection,
+  findOptions,
+  batchedUpdateOptions
+) {
+  batchedUpdate(
+    collection,
+    query,
+    update,
+    projection,
+    findOptions,
+    batchedUpdateOptions
+  )
+    .then(processed => {
+      console.error({ processed })
+      process.exit(0)
+    })
+    .catch(error => {
+      console.error({ error })
+      process.exit(1)
+    })
+}
+
+module.exports = {
+  READ_PREFERENCE_SECONDARY,
+  objectIdFromInput,
+  renderObjectId,
+  batchedUpdate,
+  batchedUpdateWithResultHandling,
+}

libraries/mongo-utils/buildscript.txt

@@ -0,0 +1,10 @@
+mongo-utils
+--dependencies=None
+--docker-repos=gcr.io/overleaf-ops
+--env-add=
+--env-pass-through=
+--esmock-loader=False
+--is-library=True
+--node-version=20.18.2
+--public-repo=False
+--script-version=4.7.0

libraries/mongo-utils/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "@overleaf/mongo-utils",
+  "version": "0.0.1",
+  "description": "utilities to help working with mongo",
+  "main": "index.js",
+  "scripts": {
+    "test": "npm run lint && npm run format && npm run types:check && npm run test:unit",
+    "test:unit": "mocha --exit test/**/*.{js,cjs}",
+    "lint": "eslint --ext .js --ext .cjs --ext .ts --max-warnings 0 --format unix .",
+    "lint:fix": "eslint --fix --ext .js --ext .cjs --ext .ts .",
+    "format": "prettier --list-different $PWD/'**/*.{js,cjs,ts}'",
+    "format:fix": "prettier --write $PWD/'**/*.{js,cjs,ts}'",
+    "test:ci": "npm run test:unit",
+    "types:check": "tsc --noEmit"
+  },
+  "author": "Overleaf (https://www.overleaf.com)",
+  "license": "AGPL-3.0-only",
+  "dependencies": {
+    "mongodb": "6.12.0",
+    "mongodb-legacy": "6.1.3"
+  },
+  "devDependencies": {
+    "chai": "^4.3.6",
+    "mocha": "^11.1.0",
+    "sandboxed-module": "^2.0.4",
+    "sinon": "^9.2.4",
+    "sinon-chai": "^3.7.0",
+    "typescript": "^5.0.4"
+  }
+}

libraries/mongo-utils/test/setup.js

@@ -0,0 +1,11 @@
+const chai = require('chai')
+const sinonChai = require('sinon-chai')
+const SandboxedModule = require('sandboxed-module')
+
+// Chai configuration
+chai.should()
+chai.use(sinonChai)
+
+SandboxedModule.configure({
+  globals: { Buffer, JSON, console, process },
+})

libraries/mongo-utils/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.backend.json",
+  "include": [
+    "**/*.js",
+    "**/*.cjs"
+  ]
+}

libraries/o-error/.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+charset = utf-8
+indent_style = space
+indent_size = 2
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true

libraries/o-error/.gitignore

@@ -0,0 +1,5 @@
+.nyc_output
+coverage
+node_modules/
+
+.npmrc

libraries/o-error/.nvmrc

@@ -0,0 +1 @@
+20.18.2

libraries/o-error/CHANGELOG.md

@@ -0,0 +1,3 @@
+# @overleaf/o-error History
+
+Please see the [Releases on GitHub](https://github.com/overleaf/o-error/releases) for history.

libraries/o-error/LICENSE

@@ -0,0 +1,21 @@
+The MIT License
+
+Copyright (c) 2016-2018 Overleaf https://www.overleaf.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

libraries/o-error/README.md

@@ -0,0 +1,475 @@
+# @overleaf/o-error
+
+[![npm version](https://badge.fury.io/js/%40overleaf%2Fo-error.svg)](https://badge.fury.io/js/%40overleaf%2Fo-error)
+[![CircleCI](https://circleci.com/gh/overleaf/o-error.svg?style=svg)](https://circleci.com/gh/overleaf/o-error)
+[![Coverage Status](https://coveralls.io/repos/github/overleaf/o-error/badge.svg?branch=master)](https://coveralls.io/github/overleaf/o-error?branch=master)
+
+Light-weight helpers for handling JavaScript Errors in node.js and the browser.
+
+- Get long stack traces across async functions and callbacks with `OError.tag`.
+- Easily make custom `Error` subclasses.
+- Wrap internal errors, preserving the original errors for logging as `causes`.
+- Play nice with error logging services by keeping data in attached `info` objects instead of the error message.
+
+## Table of Contents
+
+<!-- toc -->
+
+- [Long Stack Traces with `OError.tag`](#long-stack-traces-with-oerrortag)
+  * [The Problem](#the-problem)
+  * [The Solution](#the-solution)
+  * [Adding More Info](#adding-more-info)
+  * [`async`/`await`](#asyncawait)
+  * [Better Async Stack Traces in Node 12+](#better-async-stack-traces-in-node-12)
+  * [Caveat: Shared Error Instances](#caveat-shared-error-instances)
+- [Create Custom Error Classes](#create-custom-error-classes)
+  * [Attaching Extra Info](#attaching-extra-info)
+  * [Wrapping an Internal Error](#wrapping-an-internal-error)
+- [OError API Reference](#oerror-api-reference)
+  * [new OError(message, [info], [cause])](#new-oerrormessage-info-cause)
+  * [oError.withInfo(info) ⇒ this](#oerrorwithinfoinfo--this)
+  * [oError.withCause(cause) ⇒ this](#oerrorwithcausecause--this)
+  * [OError.maxTags : Number](#oerrormaxtags--number)
+  * [OError.tag(error, [message], [info]) ⇒ Error](#oerrortagerror-message-info--error)
+  * [OError.getFullInfo(error) ⇒ Object](#oerrorgetfullinfoerror--object)
+  * [OError.getFullStack(error) ⇒ string](#oerrorgetfullstackerror--string)
+- [References](#references)
+
+<!-- tocstop -->
+
+## Long Stack Traces with `OError.tag`
+
+### The Problem
+
+While JavaScript errors have stack traces, they only go back to the start of the latest tick, so they are often not very useful. For example:
+
+```js
+const demoDatabase = {
+  findUser(id, callback) {
+    process.nextTick(() => {
+      // return result asynchronously
+      if (id === 42) {
+        callback(null, { name: 'Bob' })
+      } else {
+        callback(new Error('not found'))
+      }
+    })
+  },
+}
+
+function sayHi1(userId, callback) {
+  demoDatabase.findUser(userId, (err, user) => {
+    if (err) return callback(err)
+    callback(null, 'Hi ' + user.name)
+  })
+}
+
+sayHi1(43, (err, result) => {
+  if (err) {
+    console.error(err)
+  } else {
+    console.log(result)
+  }
+})
+```
+
+The resulting error's stack trace doesn't make any mention of our `sayHi1` function; it starts at the `nextTick` built-in:
+
+```
+Error: not found
+    at process.nextTick (repl:8:18)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+```
+
+In practice, it's often even worse, like
+
+```
+DBError: socket connection refused
+    at someObscureLibraryFunction (...)
+    at ...
+```
+
+### The Solution
+
+Before passing the error to a callback, call the `OError.tag` function to capture a stack trace at the call site:
+
+```js
+const OError = require('.')
+
+function sayHi2(userId, callback) {
+  demoDatabase.findUser(userId, (err, user) => {
+    if (err) return callback(OError.tag(err))
+    callback(null, 'Hi ' + user.name)
+  })
+}
+
+sayHi2(43, (err, result) => {
+  if (err) {
+    console.error(OError.getFullStack(OError.tag(err)))
+  } else {
+    console.log(result)
+  }
+})
+```
+
+And use `OError.getFullStack` to reconstruct the full stack, including the tagged errors:
+
+```
+Error: not found
+    at process.nextTick (repl:8:18)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+TaggedError
+    at demoDatabase.findUser (repl:3:37)
+    at process.nextTick (repl:8:9)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+TaggedError
+    at sayHi2 (repl:3:46)
+    at demoDatabase.findUser (repl:3:21)
+    at process.nextTick (repl:8:9)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+```
+
+The full stack contains the original error's stack and also the `TaggedError` stacks. There's some redundancy, but it's better to have too much information than too little.
+
+### Adding More Info
+
+You can add more information at each `tag` call site: a message and an `info` object with custom properties.
+
+```js
+function sayHi3(userId, callback) {
+  demoDatabase.findUser(userId, (err, user) => {
+    if (err) return callback(OError.tag(err, 'failed to find user', { userId }))
+    callback(null, 'Hi ' + user.name)
+  })
+}
+
+sayHi3(43, (err, result) => {
+  if (err) {
+    OError.tag(err, 'failed to say hi')
+    console.error(OError.getFullStack(err))
+    console.error(OError.getFullInfo(err))
+  } else {
+    console.log(result)
+  }
+})
+```
+
+The `OError.getFullInfo` property merges all of the `info`s from the tags together into one object. This logs a full stack trace with `failed to ...` annotations and an `info` object that contains the `userId` that it failed to find:
+
+```
+Error: not found
+    at process.nextTick (repl:8:18)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+TaggedError: failed to find user
+    at demoDatabase.findUser (repl:3:37)
+    at process.nextTick (repl:8:9)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+TaggedError: failed to say hi
+    at sayHi3 (repl:3:12)
+    at demoDatabase.findUser (repl:3:21)
+    at process.nextTick (repl:8:9)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+
+{ userId: 43 }
+```
+
+Logging this information (or reporting it to an error monitoring service) hopefully gives you a good start to figuring out what went wrong.
+
+### `async`/`await`
+
+The `OError.tag` approach works with both async/await and callback-oriented code. When using async/await, the pattern is to catch an error, tag it and rethrow:
+
+```js
+const promisify = require('util').promisify
+demoDatabase.findUserAsync = promisify(demoDatabase.findUser)
+
+async function sayHi4(userId) {
+  try {
+    const user = await demoDatabase.findUserAsync(userId)
+    return `Hi ${user.name}`
+  } catch (error) {
+    throw OError.tag(error, 'failed to find user', { userId })
+  }
+}
+
+async function main() {
+  try {
+    await sayHi4(43)
+  } catch (error) {
+    OError.tag(error, 'failed to say hi')
+    console.error(OError.getFullStack(error))
+    console.error(OError.getFullInfo(error))
+  }
+}
+main()
+```
+
+The resulting full stack trace points to `sayHi4` in `main`, as expected:
+
+```
+Error: not found
+    at process.nextTick (repl:8:18)
+    at process._tickCallback (internal/process/next_tick.js:61:11)
+TaggedError: failed to find user
+    at sayHi4 (repl:6:18)
+    at process._tickCallback (internal/process/next_tick.js:68:7)
+TaggedError: failed to say hi
+    at main (repl:5:12)
+    at process._tickCallback (internal/process/next_tick.js:68:7)
+
+{ userId: 43 }
+```
+
+### Better Async Stack Traces in Node 12+
+
+The above output is from node 10. Node 12 has improved stack traces for async code that uses native promises. However, until your whole stack, including all libraries, is using async/await and native promises, you're still likely to get unhelpful stack traces. So, the tagging approach still adds value, even in node 12. (And the `info` from tagging can add value even to a good stack trace, because it can contain clues about the input the caused the error.)
+
+### Caveat: Shared Error Instances
+
+Some libraries, such as `ioredis`, may return the same `Error` instance to multiple callbacks. In this case, the tags may be misleading, because they will be a mixture of the different 'stacks' that lead to the error. You can either accept this or choose to instead wrap the errors from these libraries with new `OError` instances using `withCause`.
+
+In the worst case, a library that always returns a single instance of an error could cause a resource leak. To prevent this, `OError` will only add up to `OError.maxTags` (default 100) tags to a single Error instance.
+
+## Create Custom Error Classes
+
+Broadly speaking, there are two kinds of errors: those we try to recover from, and those for which we give up (i.e. a 5xx response in a web application). For the latter kind, we usually just want to log a message and stack trace useful for debugging, which `OError.tag` helps with.
+
+To recover from an error, we usually need to know what kind of error it was and perhaps to check some of its properties. Defining a custom Error subclass is a good way to do this. Callers can check the type of the error either with `instanceof` or using a custom property, such as `code`.
+
+With ES6 classes, creating a custom error subclass is mostly as simple as `extends Error`. One extra line is required to set the error's `name` appropriately, and inheriting from `OError` handles this implementation detail. Here's an example:
+
+```js
+class UserNotFoundError extends OError {
+  constructor() {
+    super('user not found')
+  }
+}
+
+try {
+  throw new UserNotFoundError()
+} catch (error) {
+  console.error(`instanceof Error: ${error instanceof Error}`)
+  console.error(
+    `instanceof UserNotFoundError: ${error instanceof UserNotFoundError}`
+  )
+  console.error(error.stack)
+}
+```
+
+```
+instanceof Error: true
+instanceof UserNotFoundError: true
+UserNotFoundError: user not found
+    at repl:2:9
+    ...
+```
+
+### Attaching Extra Info
+
+Whether for helping with error recovery or just for debugging, it is often helpful to include some of the state that caused the error in the error. One way to do this is to put it in the message, but this has a few problems:
+
+- Even if the error is later handled and recovered from, we spend time stringifying the state to add it to the error message.
+- Error monitoring systems often look at the message when trying to group similar errors together, and they can get confused by the ever-changing messages.
+- When using structured logging, you lose the ability to easily query or filter the logs based on the state; instead clever regexes may be required to get it out of the messages.
+
+Instead, `OError`s (and subclasses) support an `info` object that can contain arbitrary data. Using `info`, we might write the above example as:
+
+```js
+class UserNotFoundError extends OError {
+  constructor(userId) {
+    super('user not found', { userId })
+  }
+}
+
+try {
+  throw new UserNotFoundError(123)
+} catch (error) {
+  console.error(OError.getFullStack(error))
+  console.error(OError.getFullInfo(error))
+}
+```
+
+```
+UserNotFoundError: user not found
+    at repl:2:9
+    ...
+{ userId: 123 }
+```
+
+The `OError.getFullInfo` helper merges the `info` on custom errors and any info added with `OError.tag` on its way up the stack. It is intended for use when logging errors. If trying to recover from an error that is known to be a `UserNotFoundError`, it is usually better to interrogate `error.info.userId` directly.
+
+### Wrapping an Internal Error
+
+Detecting a condition like 'user not found' in the example above often starts with an internal database error. It is possible to just let the internal database error propagate all the way up through the stack, but this makes the code more coupled to the internals of the database (or database driver). It is often cleaner to handle and wrap the internal error in one that is under your control. Tying up the examples above:
+
+```js
+async function sayHi5(userId) {
+  try {
+    const user = await demoDatabase.findUserAsync(userId)
+    return `Hi ${user.name}`
+  } catch (error) {
+    if (error.message === 'not found') {
+      throw new UserNotFoundError(userId).withCause(error)
+    }
+  }
+}
+
+async function main() {
+  try {
+    await sayHi5(43)
+  } catch (error) {
+    OError.tag(error, 'failed to say hi')
+    console.error(OError.getFullStack(error))
+    console.error(OError.getFullInfo(error))
+  }
+}
+main()
+```
+
+The output includes the wrapping error, the tag and the cause, together with the info:
+
+```
+UserNotFoundError: user not found
+    at sayHi5 (repl:7:13)
+    at process._tickCallback (internal/process/next_tick.js:68:7)
+TaggedError: failed to say hi
+    at main (repl:5:12)
+    at process._tickCallback (internal/process/next_tick.js:68:7)
+caused by:
+    Error: not found
+        at process.nextTick (repl:8:18)
+        at process._tickCallback (internal/process/next_tick.js:61:11)
+{ userId: 43 }
+```
+
+## OError API Reference
+
+<a name="OError"></a>
+* [OError](#OError)
+    * [new OError(message, [info], [cause])](#new_OError_new)
+    * _instance_
+        * [.withInfo(info)](#OError+withInfo) ⇒ <code>this</code>
+        * [.withCause(cause)](#OError+withCause) ⇒ <code>this</code>
+    * _static_
+        * [.maxTags](#OError.maxTags) : <code>Number</code>
+        * [.tag(error, [message], [info])](#OError.tag) ⇒ <code>Error</code>
+        * [.getFullInfo(error)](#OError.getFullInfo) ⇒ <code>Object</code>
+        * [.getFullStack(error)](#OError.getFullStack) ⇒ <code>string</code>
+
+<a name="new_OError_new"></a>
+
+### new OError(message, [info], [cause])
+
+| Param | Type | Description |
+| --- | --- | --- |
+| message | <code>string</code> | as for built-in Error |
+| [info] | <code>Object</code> | extra data to attach to the error |
+| [cause] | <code>Error</code> | the internal error that caused this error |
+
+<a name="OError+withInfo"></a>
+
+### oError.withInfo(info) ⇒ <code>this</code>
+Set the extra info object for this error.
+
+**Kind**: instance method of [<code>OError</code>](#OError)  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| info | <code>Object</code> | extra data to attach to the error |
+
+<a name="OError+withCause"></a>
+
+### oError.withCause(cause) ⇒ <code>this</code>
+Wrap the given error, which caused this error.
+
+**Kind**: instance method of [<code>OError</code>](#OError)  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| cause | <code>Error</code> | the internal error that caused this error |
+
+<a name="OError.maxTags"></a>
+
+### OError.maxTags : <code>Number</code>
+Maximum number of tags to apply to any one error instance. This is to avoid
+a resource leak in the (hopefully unlikely) case that a singleton error
+instance is returned to many callbacks. If tags have been dropped, the full
+stack trace will include a placeholder tag `... dropped tags`.
+
+Defaults to 100. Must be at least 1.
+
+**Kind**: static property of [<code>OError</code>](#OError)  
+<a name="OError.tag"></a>
+
+### OError.tag(error, [message], [info]) ⇒ <code>Error</code>
+Tag debugging information onto any error (whether an OError or not) and
+return it.
+
+**Kind**: static method of [<code>OError</code>](#OError)  
+**Returns**: <code>Error</code> - the modified `error` argument  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| error | <code>Error</code> | the error to tag |
+| [message] | <code>string</code> | message with which to tag `error` |
+| [info] | <code>Object</code> | extra data with wich to tag `error` |
+
+**Example** *(An error in a callback)*  
+```js
+function findUser(name, callback) {
+  fs.readFile('/etc/passwd', (err, data) => {
+    if (err) return callback(OError.tag(err, 'failed to read passwd'))
+    // ...
+  })
+}
+```
+**Example** *(A possible error in a callback)*  
+```js
+function cleanup(callback) {
+  fs.unlink('/tmp/scratch', (err) => callback(err && OError.tag(err)))
+}
+```
+**Example** *(An error with async/await)*  
+```js
+async function cleanup() {
+  try {
+    await fs.promises.unlink('/tmp/scratch')
+  } catch (err) {
+    throw OError.tag(err, 'failed to remove scratch file')
+  }
+}
+```
+<a name="OError.getFullInfo"></a>
+
+### OError.getFullInfo(error) ⇒ <code>Object</code>
+The merged info from any `tag`s and causes on the given error.
+
+If an info property is repeated, the last one wins.
+
+**Kind**: static method of [<code>OError</code>](#OError)  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| error | <code>Error</code> \| <code>null</code> \| <code>undefined</code> | any error (may or may not be an `OError`) |
+
+<a name="OError.getFullStack"></a>
+
+### OError.getFullStack(error) ⇒ <code>string</code>
+Return the `stack` property from `error`, including the `stack`s for any
+tagged errors added with `OError.tag` and for any `cause`s.
+
+**Kind**: static method of [<code>OError</code>](#OError)  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| error | <code>Error</code> \| <code>null</code> \| <code>undefined</code> | any error (may or may not be an `OError`) |
+<!-- END API REFERENCE -->
+
+## References
+
+- [MDN: Error](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error)
+- [Error Handling in Node.js](https://www.joyent.com/node-js/production/design/errors)
+- [verror](https://github.com/joyent/node-verror)
+- [Custom JavaScript Errors in ES6](https://medium.com/@xjamundx/custom-javascript-errors-in-es6-aa891b173f87)
+- [Custom errors, extending Error](https://javascript.info/custom-errors)
+- https://gist.github.com/justmoon/15511f92e5216fa2624b (some tests are based largely on this gist)