Synapse 1.19.0rc1 (2020-08-13)
==============================

Removal warning
---------------

As outlined in the [previous release](https://github.com/matrix-org/synapse/releases/tag/v1.18.0), we are no longer publishing Docker images with the `-py3` tag suffix. On top of that, we have also removed the `latest-py3` tag. Please see [the announcement in the upgrade notes for 1.18.0](https://github.com/matrix-org/synapse/blob/develop/UPGRADE.rst#upgrading-to-v1180).

Features
--------

- Add option to allow server admins to join rooms which fail complexity checks. Contributed by @lugino-emeritus. ([\#7902](https://github.com/matrix-org/synapse/issues/7902))
- Add an option to purge room or not with delete room admin endpoint (`POST /_synapse/admin/v1/rooms/<room_id>/delete`). Contributed by @dklimpel. ([\#7964](https://github.com/matrix-org/synapse/issues/7964))
- Add rate limiting to users joining rooms. ([\#8008](https://github.com/matrix-org/synapse/issues/8008))
- Add a `/health` endpoint to every configured HTTP listener that can be used as a health check endpoint by load balancers. ([\#8048](https://github.com/matrix-org/synapse/issues/8048))
- Allow login to be blocked based on the values of SAML attributes. ([\#8052](https://github.com/matrix-org/synapse/issues/8052))
- Allow guest access to the `GET /_matrix/client/r0/rooms/{room_id}/members` endpoint, according to MSC2689. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#7314](https://github.com/matrix-org/synapse/issues/7314))

Bugfixes
--------

- Fix a bug introduced in Synapse v1.7.2 which caused inaccurate membership counts in the room directory. ([\#7977](https://github.com/matrix-org/synapse/issues/7977))
- Fix a long standing bug: 'Duplicate key value violates unique constraint "event_relations_id"' when message retention is configured. ([\#7978](https://github.com/matrix-org/synapse/issues/7978))
- Fix "no create event in auth events" when trying to reject invitation after inviter leaves. Bug introduced in Synapse v1.10.0. ([\#7980](https://github.com/matrix-org/synapse/issues/7980))
- Fix various comments and minor discrepencies in server notices code. ([\#7996](https://github.com/matrix-org/synapse/issues/7996))
- Fix a long standing bug where HTTP HEAD requests resulted in a 400 error. ([\#7999](https://github.com/matrix-org/synapse/issues/7999))
- Fix a long-standing bug which caused two copies of some log lines to be written when synctl was used along with a MemoryHandler logger. ([\#8011](https://github.com/matrix-org/synapse/issues/8011), [\#8012](https://github.com/matrix-org/synapse/issues/8012))

Updates to the Docker image
---------------------------

- We no longer publish Docker images with the `-py3` tag suffix, as [announced in the upgrade notes](https://github.com/matrix-org/synapse/blob/develop/UPGRADE.rst#upgrading-to-v1180). ([\#8056](https://github.com/matrix-org/synapse/issues/8056))

Improved Documentation
----------------------

- Document how to set up a client .well-known file and fix several pieces of outdated documentation. ([\#7899](https://github.com/matrix-org/synapse/issues/7899))
- Improve workers docs. ([\#7990](https://github.com/matrix-org/synapse/issues/7990), [\#8000](https://github.com/matrix-org/synapse/issues/8000))
- Fix typo in `docs/workers.md`. ([\#7992](https://github.com/matrix-org/synapse/issues/7992))
- Add documentation for how to undo a room shutdown. ([\#7998](https://github.com/matrix-org/synapse/issues/7998), [\#8010](https://github.com/matrix-org/synapse/issues/8010))

Internal Changes
----------------

- Reduce the amount of whitespace in JSON stored and sent in responses. Contributed by David Vo. ([\#7372](https://github.com/matrix-org/synapse/issues/7372))
- Switch to the JSON implementation from the standard library and bump the minimum version of the canonicaljson library to 1.2.0. ([\#7936](https://github.com/matrix-org/synapse/issues/7936), [\#7979](https://github.com/matrix-org/synapse/issues/7979))
- Convert various parts of the codebase to async/await. ([\#7947](https://github.com/matrix-org/synapse/issues/7947), [\#7948](https://github.com/matrix-org/synapse/issues/7948), [\#7949](https://github.com/matrix-org/synapse/issues/7949), [\#7951](https://github.com/matrix-org/synapse/issues/7951), [\#7963](https://github.com/matrix-org/synapse/issues/7963), [\#7973](https://github.com/matrix-org/synapse/issues/7973), [\#7975](https://github.com/matrix-org/synapse/issues/7975), [\#7976](https://github.com/matrix-org/synapse/issues/7976), [\#7981](https://github.com/matrix-org/synapse/issues/7981), [\#7987](https://github.com/matrix-org/synapse/issues/7987), [\#7989](https://github.com/matrix-org/synapse/issues/7989), [\#8003](https://github.com/matrix-org/synapse/issues/8003), [\#8014](https://github.com/matrix-org/synapse/issues/8014), [\#8016](https://github.com/matrix-org/synapse/issues/8016), [\#8027](https://github.com/matrix-org/synapse/issues/8027), [\#8031](https://github.com/matrix-org/synapse/issues/8031), [\#8032](https://github.com/matrix-org/synapse/issues/8032), [\#8035](https://github.com/matrix-org/synapse/issues/8035), [\#8042](https://github.com/matrix-org/synapse/issues/8042), [\#8044](https://github.com/matrix-org/synapse/issues/8044), [\#8045](https://github.com/matrix-org/synapse/issues/8045), [\#8061](https://github.com/matrix-org/synapse/issues/8061), [\#8062](https://github.com/matrix-org/synapse/issues/8062), [\#8063](https://github.com/matrix-org/synapse/issues/8063), [\#8066](https://github.com/matrix-org/synapse/issues/8066), [\#8069](https://github.com/matrix-org/synapse/issues/8069), [\#8070](https://github.com/matrix-org/synapse/issues/8070))
- Move some database-related log lines from the default logger to the database/transaction loggers. ([\#7952](https://github.com/matrix-org/synapse/issues/7952))
- Add a script to detect source code files using non-unix line terminators. ([\#7965](https://github.com/matrix-org/synapse/issues/7965), [\#7970](https://github.com/matrix-org/synapse/issues/7970))
- Log the SAML session ID during creation. ([\#7971](https://github.com/matrix-org/synapse/issues/7971))
- Implement new experimental push rules for some users. ([\#7997](https://github.com/matrix-org/synapse/issues/7997))
- Remove redundant and unreliable signature check for v1 Identity Service lookup responses. ([\#8001](https://github.com/matrix-org/synapse/issues/8001))
- Improve the performance of the register endpoint. ([\#8009](https://github.com/matrix-org/synapse/issues/8009))
- Reduce less useful output in the newsfragment CI step. Add a link to the changelog section of the contributing guide on error. ([\#8024](https://github.com/matrix-org/synapse/issues/8024))
- Rename storage layer objects to be more sensible. ([\#8033](https://github.com/matrix-org/synapse/issues/8033))
- Change the default log config to reduce disk I/O and storage for new servers. ([\#8040](https://github.com/matrix-org/synapse/issues/8040))
- Add an assertion on `prev_events` in `create_new_client_event`. ([\#8041](https://github.com/matrix-org/synapse/issues/8041))
- Add a comment to `ServerContextFactory` about the use of `SSLv23_METHOD`. ([\#8043](https://github.com/matrix-org/synapse/issues/8043))
- Log `OPTIONS` requests at `DEBUG` rather than `INFO` level to reduce amount logged at `INFO`. ([\#8049](https://github.com/matrix-org/synapse/issues/8049))
- Reduce amount of outbound request logging at `INFO` level. ([\#8050](https://github.com/matrix-org/synapse/issues/8050))
- It is no longer necessary to explicitly define `filters` in the logging configuration. (Continuing to do so is redundant but harmless.) ([\#8051](https://github.com/matrix-org/synapse/issues/8051))
- Add and improve type hints. ([\#8058](https://github.com/matrix-org/synapse/issues/8058), [\#8064](https://github.com/matrix-org/synapse/issues/8064), [\#8060](https://github.com/matrix-org/synapse/issues/8060), [\#8067](https://github.com/matrix-org/synapse/issues/8067))

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

If we got an error persisting an event, we would try to remove the push actions
asynchronously, which would lead to a 'Re-starting finished log context'
warning.

I don't think there's any need for this to be asynchronous.

* Empty federation transmission queues when we are backing off.

Fixes #7828.

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

* Address feedback

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

* Reword newsfile

Change HomeServer definition to work with typing.

We do this to prevent foot guns. The default config uses a MemoryFilter,
but users are free to change to logging to files directly. If they do
then they have to ensure to set the `filters: [context]` on the right
handler, otherwise records get written with the wrong context.

Instead we move the logic to happen when we generate a record, which is
when we *log* rather than *handle*.

(It's possible to add filters to loggers in the config, however they
don't apply to descendant loggers and so they have to be manually set on
*every* logger used in the code base)

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

We do this to prevent foot guns. The default config uses a MemoryFilter,
but users are free to change to logging to files directly. If they do
then they have to ensure to set the `filters: [context]` on the right
handler, otherwise records get written with the wrong context.

Instead we move the logic to happen when we generate a record, which is
when we *log* rather than *handle*.

(It's possible to add filters to loggers in the config, however they
don't apply to descendant loggers and so they have to be manually set on
*every* logger used in the code base)

c.f. #8021 

A lot of the code here is to change the `Completed 200 OK` logging to include the request URI so that we can drop the `Sending request...` log line.

Some notes:

1. We won't log retries, which may be confusing considering the time taken log line includes retries and sleeps.
2. The `_send_request_with_optional_trailing_slash` will always be logged *without* the forward slash, even if it succeeded only with the forward slash.

* Change default log config to buffer by default.

This batches up writes to the filesystem, which is more efficient for
disk I/O. This means that it can take some time for logs to get written
to disk. Note that ERROR logs (and above) immediately flush the buffer.

This only effects new installs, as we only write the log config if
started with `--generate-config` (in the same way we do for generating
signing keys).

* Default to keeping last 4 days of logs.

This hopefully reduces the amount of logs kept for new servers. Keeping
the last 1GB of logs is likely overkill for new servers, but equally may
not be enough for busy ones.

Instead, we keep the last four days worth of logs, enough so that admins
can investigate any problems that happened over e.g. a long weekend.

Duplicating function signatures between server.py and server.pyi is
silly. This commit changes that by changing all `build_*` methods to
`get_*` methods and changing the `_make_dependency_method` to work work
as a descriptor that caches the produced value.

There are some changes in other files that were made to fix the typing
in server.py.

Hopefully this mostly speaks for itself. I also did a bit of cleaning up of the
error handling.

Fixes #8047

I think this would have caught all the cases in
https://github.com/matrix-org/synapse/issues/7642 - and I think a 500 makes
more sense here than a 403

With an undocumented configuration setting to enable them for specific users.