Synapse 1.57 released

Hey everyone! Guess what? Synapse 1.57 has just been released! Let's see what's new in this version!

Application services

Application services are piece of software that have privileged access to some of the homeserver's features. For example, they can create and manage multiple users at the same time, which is especially useful for bridges.

This release of Synapse changes the way Synapse manually manages transaction identifiers when talking to application services (a transaction being a group of events the application service should know about). While this doesn't have much impact on the everyday life of a server administrator (besides fixing a bug and paving the way for future performance improvements), this change means server admins should take extra care when updating Synapse.

More specifically, if you are running a dedicated Synapse worker for handling traffic related to application services, this worker must be stopped when upgrading the main Synapse process to ensure the update is performed safely. See the upgrade notes for more information about this change, and instructions on recovering from an incorrect upgrade.

This release of Synapse also continues work on bringing end-to-end capabilities to application services, which I was already telling you about in the Synapse 1.50 release blog post. More specifically, Synapse now supports sending device list updates to applications services, as part of implementing MSC3202. This is still very experimental and definitely not production ready, but also very exciting!

Improvements to the module system

Modules allow third-party developers to expand Synapse with extra features that wouldn't necessarily fit into the Matrix specification and/or ecosystem. In the past release of Synapse, we have been improving this system to add more functionality to it, and this one is no exception!

Synapse modules can now implement new callbacks to react to account data updates, as well as to react to new 3PID (email address, phone number) associations. On the latter, note that this callback will only be called after a 3PID has been validated on the homeserver, and does not trigger when the validation happens on an identity server (e.g. when publishing a 3PID so that other users can look it up).

The ModuleApi (which is the Python class enabling modules to interact with Synapse) has also been updated to allow module to read and write global account data. This can be done by using the new AccountDataManager class, which can be accessed as api.account_data_manager (where api is an instance of ModuleApi).

The module API has also been updated with a new method, to allow modules to promote an existing user to server administrator (or demote a server administrator to a normal user). This follows up on an improvement introduced in Synapse 1.56 allowing modules to promote users to server administrators when registering them.

Everything else

This release also includes a performance improvement for workers handling /sync requests. While this change makes starting this kind of workers slightly more heavy performance-wise, it aims at improving the load associated with the first /sync requests hitting it right after starting. See this comment for more details.

Synapse 1.57 also now includes bundled aggregations in message search results by default, as MSC3666 has been accepted and has finished its final comment period.

See the full changelog for a complete list of changes in this release. Also please have a look at the upgrade notes for this version.

Synapse is a Free and Open Source Software project, and we'd like to extend our thanks to everyone who contributed to this release, including (in no particular order) Beeper, Dirk Klimpel, Famedly and Jorge Florian.