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synapse/docker/complement
Paul ChobertandEric Eastwood 3c46a10955 Stabilise MSC4222: support the stable use_state_after identifiers on /sync (#20170)
Part of #19414 (Support Matrix 1.16).

⚠️ Before merging, wait for the following PRs to be merged first:
- https://github.com/element-hq/synapse/pull/20081
- https://github.com/element-hq/synapse/pull/20169
- https://github.com/element-hq/synapse/pull/20171

---

Since Matrix 1.16, the
[spec](https://spec.matrix.org/v1.19/client-server-api/#get_matrixclientv3sync)
defines the stable identifiers for
[MSC4222](https://github.com/matrix-org/matrix-spec-proposals/pull/4222):
the `use_state_after` query parameter on `GET /_matrix/client/v3/sync`,
and the `state_after` room response field:

> **`use_state_after`** — `boolean` — Controls whether to receive state
changes between the previous sync and the start of the timeline, or
between the previous sync and the end of the timeline. If this is set to
`true`, servers MUST respond with the state between the previous sync
and the end of the timeline in `state_after` and MUST omit `state`. […]
>
> **`state_after`** — […] Required if `use_state_after` was set to true
in the request, even if it is empty. Added in `v1.16`
>
> — [Matrix
Spec](https://spec.matrix.org/v1.19/client-server-api/#get_matrixclientv3sync)

Synapse so far only implemented the unstable identifiers
(`org.matrix.msc4222.use_state_after` /
`org.matrix.msc4222.state_after`), gated behind the `msc4222_enabled`
experimental flag and the per-user experimental features admin API.

This PR:

- accepts the stable `use_state_after` query parameter, unconditionally,
and responds with the stable `state_after` field. The unstable query
parameter is kept for a transition period; clients opting in with it get
the unstable response field name back, so unstable-era clients see an
unchanged wire format. If both parameters are set, the stable one wins.
- removes the `msc4222_enabled` experimental flag and the `msc4222`
per-user feature from the experimental features admin API, since the
behaviour is no longer gated.

### Pull Request Checklist

<!-- Please read
https://element-hq.github.io/synapse/latest/development/contributing_guide.html
before submitting your pull request -->

* [x] Pull request is based on the develop branch
* [x] Pull request includes a [changelog
file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog).
The entry should:
- Be a short description of your change which makes sense to users.
"Fixed a bug that prevented receiving messages from other servers."
instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
  - Use markdown where necessary, mostly for `code blocks`.
  - End with either a period (.) or an exclamation mark (!).
  - Start with a capital letter.
- Feel free to credit yourself, by adding a sentence "Contributed by
@github_username." or "Contributed by [Your Name]." to the end of the
entry.
* [x] [Code
style](https://element-hq.github.io/synapse/latest/code_style.html) is
correct (run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))

---------

Co-authored-by: Eric Eastwood <madlittlemods@gmail.com>
2026-10-08 15:14:23 +02:00
..
2024-02-20 17:14:50 +00:00

Unified Complement image for Synapse

This is an image for testing Synapse with the Complement integration test suite. It contains some insecure defaults that are only suitable for testing purposes, so please don't use this image for a production server.

This multi-purpose image is built on top of Dockerfile-workers in the parent directory and can be switched using environment variables between the following configurations:

  • Monolithic Synapse with SQLite (default, or SYNAPSE_COMPLEMENT_DATABASE=sqlite)
  • Monolithic Synapse with Postgres (SYNAPSE_COMPLEMENT_DATABASE=postgres)
  • Workerised Synapse with Postgres (SYNAPSE_COMPLEMENT_DATABASE=postgres and SYNAPSE_COMPLEMENT_USE_WORKERS=true)

The image is self-contained; it contains an integrated Postgres, Redis and Nginx.

How to get Complement to pass the environment variables through

To pass these environment variables, use Complement's COMPLEMENT_SHARE_ENV_PREFIX variable to configure an environment prefix to pass through, then prefix the above options with that prefix.

Example:

COMPLEMENT_SHARE_ENV_PREFIX=PASS_ PASS_SYNAPSE_COMPLEMENT_DATABASE=postgres

Consult scripts-dev/complement.sh in the repository root for a real example.

How to modify homeserver.yaml for Complement tests

It's common for MSCs to be gated behind a feature flag like this:

experimental_features:
  faster_joins: true

To modify this for the Complement image, modify ./conf/workers-shared-extra.yaml.j2. Despite the name, this will affect non-worker mode as well. Remember to rebuild the image (so don't use -e if using complement.sh).