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181 Stars 26 Forks Mozilla Public License 2.0 1.2K Commits 99 Opened issues


Sync Storage server in Rust

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License: MPL 2.0 Build Status Connect to Matrix via the Riot webapp


Mozilla Sync Storage built with Rust.

System Requirements

  • cmake
  • gcc
  • golang
  • libcurl4-openssl-dev
  • libssl-dev
  • make
  • pkg-config
  • Rust stable
  • MySQL 5.7 (or compatible)
    • libmysqlclient (
      brew install mysql
      on macOS,
      apt install libmysqlclient-dev
      on Ubuntu,
      apt install libmariadb-dev-compat
      on Debian)

Depending on your OS, you may also need to install

, and
. Note: if the code complies cleanly, but generates a Segmentation Fault within Sentry init, you probably are missing

Local Setup

  1. Follow the instructions below to use either MySQL or Spanner as your DB.
  2. Now
    cp config/local.example.toml config/local.toml
    . Open
    and make sure you have the desired settings configured. For a complete list of available configuration options, check out docs/
  3. make run
    starts the server in debug mode, using your new
    file for config options. Or, simply
    cargo run
    with your own config options provided as env vars.
  4. Visit
    to make sure the server is running.


Durable sync needs only a valid mysql DSN in order to set up connections to a MySQL database. The database can be local and is usually specified with a DSN like:

mysql://_user_:[email protected]_host_/_database_

To setup a fresh MySQL DB and user: (

mysql -u root
CREATE USER "sample_user"@"localhost" IDENTIFIED BY "sample_password";
CREATE DATABASE syncstorage_rs;

GRANT ALL PRIVILEGES on syncstorage_rs.* to [email protected];


Authenticating via OAuth

The correct way to authenticate with Spanner is by generating an OAuth token and pointing your local application server to the token. In order for this to work, your Google Cloud account must have the correct permissions; contact the Ops team to ensure the correct permissions are added to your account.

First, install the Google Cloud command-line interface by following the instructions for your operating system here. Next, run the following to log in with your Google account (this should be the Google account associated with your Mozilla LDAP credentials):

gcloud auth application-default login
The above command will prompt you to visit a webpage in your browser to complete the login process. Once completed, ensure that a file called
has been created in the appropriate directory (on Linux, this directory is
). The Google Cloud SDK knows to check this location for your credentials, so no further configuration is needed.
Key Revocation

Accidents happen, and you may need to revoke the access of a set of credentials if they have been publicly leaked. To do this, run:

gcloud auth application-default revoke
This will revoke the access of the credentials currently stored in the
file. If the file in that location does not contain the leaked credentials, you will need to copy the file containing the leaked credentials to that location and re-run the above command. You can ensure that the leaked credentials are no longer active by attempting to connect to Spanner using the credentials. If access has been revoked, your application server should print an error saying that the token has expired or has been revoked.

Authenticating via Service Account

An alternative to authentication via application default credentials is authentication via a service account. Note that this method of authentication is not recommended. Service accounts are intended to be used by other applications or virtual machines and not people. See this article for more information.

Your system administrator will be able to tell you which service account keys have access to the Spanner instance to which you are trying to connect. Once you are given the email identifier of an active key, log into the Google Cloud Console Service Accounts page. Be sure to select the correct project.

  • Locate the email identifier of the access key and pick the vertical dot menu at the far right of the row.
  • Select "Create Key" from the pop-up menu.
  • Select "JSON" from the Dialog Box.

A proper key file will be downloaded to your local directory. It's important to safeguard that key file. For this example, we're going to name the file


The proper key file is in JSON format. An example file is provided below, with private information replaced by "

  "type": "service_account",
  "project_id": "...",
  "private_key_id": "...",
  "private_key": "...",
  "client_email": "...",
  "client_id": "...",
  "auth_uri": "",
  "token_uri": "",
  "auth_provider_x509_cert_url": "",
  "client_x509_cert_url": "..."

Note that the name

must be exactly correct to be ignored by

Connecting to Spanner

To point to a GCP-hosted Spanner instance from your local machine, follow these steps:

  1. Authenticate via either of the two methods outlined above.
  2. Open
    and replace
    with a link to your spanner instance.
  3. Open the Makefile and ensure you've correctly set you
  4. make run_spanner
  5. Visit
    to make sure the server is running.

Note, that unlike MySQL, there is no automatic migrations facility. Currently, the Spanner schema must be hand edited and modified.


Google supports an in-memory Spanner emulator, which can run on your local machine for development purposes. You can install the emulator via the gcloud CLI or Docker by following the instructions here. Once the emulator is running, you'll need to create a new instance and a new database. To create an instance using the REST API (exposed via port 9020 on the emulator), we can use

curl --request POST \
  "localhost:9020/v1/projects/$PROJECT_ID/instances" \
  --header 'Accept: application/json' \
  --header 'Content-Type: application/json' \
  --data "{\"instance\":{\"config\":\"emulator-test-config\",\"nodeCount\":1,\"displayName\":\"Test Instance\"},\"instanceId\":\"$INSTANCE_ID\"}"
Note that you may set
to your liking. To create a new database on this instance, we'll use a similar HTTP request, but we'll need to include information about the database schema. Since we don't have migrations for Spanner, we keep an up-to-date schema in
. The
utility allows us to parse this file for use in the JSON body of an HTTP POST request:
  grep -v ^-- schema.ddl \
  | sed -n 's/ \+/ /gp' \
  | tr -d '\n' \
  | sed 's/\(.*\);/\1/' \
  | jq -R -s -c 'split(";")'
Finally, to create the database:
curl -sS --request POST \
  "localhost:9020/v1/projects/$PROJECT_ID/instances/$INSTANCE_ID/databases" \
  --header 'Accept: application/json' \
  --header 'Content-Type: application/json' \
  --data "{\"createStatement\":\"CREATE DATABASE \`$DATABASE_ID\`\",\"extraStatements\":$DDL_STATEMENTS}"
Note that, again, you may set
to your liking. Make sure that the
config variable reflects your choice of project name, instance name, and database name (i.e. it should be of the format

To run an application server that points to the local Spanner emulator:

SYNC_SPANNER_EMULATOR_HOST=localhost:9010 make run_spanner

Running via Docker

This requires access to the mozilla-rust-sdk which is now available at

  1. Make sure you have Docker installed locally.
  2. Copy the contents of mozilla-rust-sdk into top level root dir here.
  3. Change cargo.toml mozilla-rust-sdk entry to point to
    "path = "mozilla-rust-sdk/googleapis-raw"
    instead of the parent dir.
  4. Comment out the
    value under
    in either docker-compose.mysql.yml or docker-compose.spanner.yml (depending on which database backend you want to run), and add this instead:
        context: .
  5. If you are using MySQL, adjust the MySQL db credentials in docker-compose.mysql.yml to match your local setup.
  6. make docker_start_mysql
    make docker_start_spanner
    - You can verify it's working by visiting localhost:8000/__heartbeat__

Connecting to Firefox

This will walk you through the steps to connect this project to your local copy of Firefox.

  1. Follow the steps outlined above for running this project using MySQL.

  2. Setup a local copy of syncserver, with a few special changes to syncserver.ini; make sure that you're using the following values (in addition to all of the other defaults):

    port = 5000

    [syncserver] public_url = http://localhost:5000/

    This value needs to match your "master_secret" for syncstorage-rs!


    [tokenserver] node_url = http://localhost:8000 sqluri = pymysql://sample_user:[email protected]/syncstorage_rs

    [endpoints] sync-1.5 = "http://localhost:8000/1.5/1"```

  1. In Firefox, go to
    . Change
  2. Restart Firefox. Now, try syncing. You should see new BSOs in your local MySQL instance.



  1. If you want to connect to the existing Sentry project for local development, login to Sentry, and go to the page with api keys. Copy the
  2. Comment out the
    line in your
  3. You can force an error to appear in Sentry by adding a
    into, just before the final
  4. Now,
  5. You may need to stop the local server after it hits the panic! before errors will appear in Sentry.


We use env_logger: set the

env var.


Unit tests

make test
- open the Makefile to adjust your
as needed.

Debugging unit test state

In some cases, it is useful to inspect the mysql state of a failed test. By default, we use the diesel testtransaction functionality to ensure test data is not committed to the database. Therefore, there is an environment variable which can be used to turn off testtransaction.

    SYNC_DATABASE_USE_TEST_TRANSACTIONS=false cargo test [testname]

Note that you will almost certainly want to pass a single test name. When running the entire test suite, data from previous tests will cause future tests to fail.

To reset the database state between test runs, drop and recreate the database in the mysql client:

    drop database syncstorage_rs; create database syncstorage_rs; use syncstorage_rs;

End-to-End tests

Functional tests live in server-syncstorage and can be run against a local server, e.g.:

  1. If you haven't already followed the instructions here to get all the dependencies for the server-syncstorage repo, you should start there.

  2. Install (Python) server-syncstorage:

     $ git clone
     $ cd server-syncstorage
     $ make build
  3. Run an instance of syncstorage-rs (

    cargo run
    in this repo).
  4. To run all tests:

     $ ./local/bin/python syncstorage/tests/functional/ http://localhost:8000#
  5. Individual tests can be specified via the

    env var:
    $ SYNC_TEST_PREFIX=test_get_collection \
        ./local/bin/python syncstorage/tests/functional/ http://localhost:8000#

Creating Releases

  1. Switch to master branch of syncstorage-rs
  2. git pull
    to ensure that the local copy is up-to-date.
  3. git pull origin master
    to make sure that you've incorporated any changes to the master branch.
  4. git diff origin/master
    to ensure that there are no local staged or uncommited changes.
  5. Bump the version number in Cargo.toml (this new version number will be designated as
     in this checklist)
  6. create a git branch for the new version
    git checkout -b release/
  7. cargo build --release
    - Build with the release profile release mode.
  8. clog -C
    - Generate release notes. We're using clog for release notes. Add a
    flag to denote major/minor/patch version, ie
    clog -C -p
  9. Review the
    file and ensure all relevant changes since the last tag are included.
  10. Create a new release in Sentry:
    VERSION={release-version-here} bash scripts/
    . If you're doing this for the first time, checkout the tips below for troubleshooting sentry cli access.
  11. git commit -am "chore: tag "
    to commit the new version and changes
  12. git tag -s -m "chore: tag " 
    to create a signed tag of the current HEAD commit for release.
  13. git push origin release/
    to push the commits to a new origin release branch
  14. git push --tags origin release/
    to push the tags to the release branch.
  15. Submit a Pull Request (PR) on github to merge the release branch to master.
  16. Go to the GitHub release, you should see the new tag with no release information.
  17. Click the
    Draft a new release
  18. Enter the <version> number for
    Tag version
  19. Copy and paste the most recent change set from
    into the release description, omitting the top 2 lines (the name and version)
  20. Once your PR merges, click [Publish Release] on the GitHub release page.

Sync server is automatically deployed to STAGE, however QA may need to be notified if testing is required. Once QA signs off, then a bug should be filed to promote the server to PRODUCTION.


  • rm Cargo.lock; cargo clean;
    - Try this if you're having problems compiling.
  • Some versions of OpenSSL 1.1.1 can conflict with grpcio's built in BoringSSL. These errors can cause syncstorage to fail to run or compile. If you see a problem related to

    you may need to specify the
    --features grpcio/openssl
    to force grpcio to use OpenSSL.


  • If you're having trouble working with Sentry to create releases, try authenticating using their self hosted server option that's outlined here Ie,
    sentry-cli --url login
    . It's also recommended to create a
    config file. See this example for the config values you'll need.

Related Documentation

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