* Add support for the stable version of MSC2778

Signed-off-by: Tulir Asokan <tulir@maunium.net>

* Expect m.login.application_service in login and password provider tests

Signed-off-by: Tulir Asokan <tulir@maunium.net>

* Prefer `HTTPStatus` over plain `int`

This is an Opinion that no-one has seemed to object to yet.

* `--disallow-untyped-defs` for `tests.rest.client.test_directory`
* Improve synapse's annotations for deleting aliases
* Test case for deleting a room alias
* Changelog

* Annotate HomeserverTestCase.servlets
* Correct annotation of federation_auth_origin
* Use AnyStr custom_headers instead of a Union

This allows (str, str) and (bytes, bytes).
This disallows (str, bytes) and (bytes, str)

* DomainSpecificString.SIGIL is a ClassVar

Signed-off-by: Dirk Klimpel <dirk@klimpel.org>

Co-authored-by: Dirk Klimpel <5740567+dklimpel@users.noreply.github.com>
Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Adds experimental support for `relation_types` and `relation_senders`
fields for filters.

Co-authored-by: reivilibre <olivier@librepush.net>

Fixes #11259

We might as well use a default value for `public_baseurl` based on
`server_name` - in many cases, it will be correct.

Fixes: #10874
Signed-off-by: Dirk Klimpel <dirk@klimpel.org>

* add code to handle missing content-type header and a test to verify that it works

* add handling for missing content-type in the /upload endpoint as well

* slightly refactor test code to put private method in approriate place

* handle possible null value for content-type when pulling from the local db

* add changelog

* refactor test and add code to handle missing content-type in cached remote media

* requested changes

* Update changelog.d/11200.bugfix

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

Make `check_event_allowed` module API callback not fail open (accept events) when an exception is raised (#11033)

Remove deprecated delete room admin API,
`POST /_synapse/admin/v1/rooms/<room_id>/delete`

Fixes https://github.com/matrix-org/synapse/issues/8308

Signed-off-by: Rafael Goncalves <rafaelgoncalves@riseup.net>

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Users admin API can now also modify user
type in addition to allowing it to be
set on user creation.

Signed-off-by: Jason Robinson <jasonr@matrix.org>
Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

Adds experimental support for MSC3440's `io.element.thread` relation
type (and the aggregation for it).

Fix setting a user's external_id via the admin API returns 500 and deletes users existing external mappings if that external ID is already mapped (#11051)

Fixes #10846

Add a test for a workaround concerning the behaviour of third-party rule modules and `SynapseError`s. (#11071)

Searches the returned HTML for an oEmbed endpoint using the
autodiscovery mechanism (`<link rel=...>`), and will request it
to generate the preview.

This is in the context of creating new module callbacks that modules in https://github.com/matrix-org/synapse-dinsic can use, in an effort to reconcile the spam checker API in synapse-dinsic with the one in mainline.

Note that a module callback already exists for 3pid invites (https://matrix-org.github.io/synapse/develop/modules/third_party_rules_callbacks.html#check_threepid_can_be_invited) but it doesn't check whether the sender of the invite is allowed to send it.

Co-authored-by: Erik Johnston <erik@matrix.org>

Signed-off-by: Andrew Ferrazzutti <fair@miscworks.net>

* Introduce `should_include_local_users_in_dir`

We exclude three kinds of local users from the user_directory tables. At
present we don't consistently exclude all three in the same places. This
commit introduces a new function to gather those exclusion conditions
together. Because we have to handle local and remote users in different
ways, I've made that function only consider the case of remote users.
It's the caller's responsibility to make the local versus remote
distinction clear and correct.

A test fixup is required. The test now hits a path which makes db
queries against the users table. The expected rows were missing, because
we were using a dummy user that hadn't actually been registered.

We also add new test cases to covert the exclusion logic.

----

By my reading this makes these changes:

* When an app service user registers or changes their profile, they will
  _not_ be added to the user directory. (Previously only support and
  deactivated users were excluded). This is consistent with the logic that
  rebuilds the user directory. See also [the discussion
  here](https://github.com/matrix-org/synapse/pull/10914#discussion_r716859548

).
* When rebuilding the directory, exclude support and disabled users from
  room sharing tables. Previously only appservice users were excluded.
* Exclude all three categories of local users when rebuilding the
  directory. Previously `_populate_user_directory_process_users` didn't do
  any exclusion.

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

* type-hint `HomeserverTestcase.setup_test_homeserver`

For better IDE completion. A small drive-by.

URL cache files are short-lived and it does not make sense to offload
them (eg. to the cloud) or back them up.