* 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>

* Pull out GetUserDirectoryTables helper
* Don't rebuild the dir in tests that don't need it

In #10796 I changed registering a user to add directory entries under.
This means we don't have to force a directory regbuild in to tests of
the user directory search.

* Move test_initial to tests/storage
* Add type hints to both test_user_directory files

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

This avoids the overhead of searching through the various
configuration classes by directly referencing the class that
the attributes are in.

It also improves type hints since mypy can now resolve the
types of the configuration variables.

* add test to check if null code points are being inserted

* add logic to detect and replace null code points before insertion into db

* lints

* add license to test

* change approach to null substitution

* add type hint for SearchEntry

* Add changelog entry

Signed-off-by: H.Shay <shaysquared@gmail.com>

* updated changelog

* update chanelog message

* remove duplicate changelog

* Update synapse/storage/databases/main/events.py remove extra space

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

* rename and move test file, update tests, delete old test file

* fix typo in comments

* update _find_highlights_in_postgres to replace null byte with space

* replace null byte in sqlite search insertion

* beef up and reorganize test for this pr

* update changelog

* add type hints and update docstring

* check db engine directly vs using env variable

* refactor tests to be less repetetive

* move rplace logic into seperate function

* requested changes

* Fix typo.

* Update synapse/storage/databases/main/search.py

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

* Update changelog.d/10820.misc

Co-authored-by: Aaron Raimist <aaron@raim.ist>

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>
Co-authored-by: reivilibre <olivier@librepush.net>
Co-authored-by: Aaron Raimist <aaron@raim.ist>

Also enables Mypy for related tests.

Outlier events don't ever have push actions associated with them, so we
can skip some expensive queries during event persistence.

Part of https://github.com/matrix-org/synapse/pull/10566

 - Fill in creator whenever we insert into the rooms table
 - Add background update to backfill any missing creator values

Ensure we only load an event from the DB once when the same event is requested multiple times at once.

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

Setting the value will help PostgreSQL free up memory by recycling
the connections in the connection pool.

Signed-off-by: Toni Spets <toni.spets@iki.fi>

This PR is tantamount to running:

    python3.8 -m com2ann -v 6 tests/

(com2ann requires python 3.8 to run)

This adds a simple best effort locking mechanism that works cross workers.

Work on https://github.com/matrix-org/matrix-doc/pull/2716

Reformat all files with the new version.

Signed-off-by: Marcus Hoffmann <bubu@bubu1.eu>

Empirically, this helped my server considerably when handling gaps in Matrix HQ. The problem was that we would repeatedly call have_seen_events for the same set of (50K or so) auth_events, each of which would take many minutes to complete, even though it's only an index scan.

The hope here is that by moving all the schema files into synapse/storage/schema, it gets a bit easier for newcomers to navigate.

It certainly got easier for me to write a helpful README. There's more to do on that front, but I'll follow up with other PRs for that.

I went through and removed a bunch of cruft that was lying around for compatibility with old Python versions. This PR also will now prevent Synapse from starting unless you're running Python 3.6+.

Part of #9744

Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.

`Signed-off-by: Jonathan de Jong <jonathan@automatia.nl&gt;`>

Related: #8334
Deprecated in: #9429 - Synapse 1.28.0 (2021-02-25)

`GET /_synapse/admin/v1/users/<user_id>` has no
- unit tests
- documentation

API in v2 is available (#5925 - 12/2019, v1.7.0).
API is misleading. It expects `user_id` and returns a list of all users.

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

Part of #9366

Adds in fixes for B006 and B008, both relating to mutable parameter lint errors.

Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>

This uses a simplified version of get_chain_cover_difference to calculate
auth chain of events.

Unfortunately this doesn't test re-joining the room since
that requires having another homeserver to query over
federation, which isn't easily doable in unit tests.

 - Update black version to the latest
 - Run black auto formatting over the codebase
    - Run autoformatting according to [`docs/code_style.md
`](https://github.com/matrix-org/synapse/blob/80d6dc9783aa80886a133756028984dbf8920168/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

We do this by allowing a single iteration to process multiple rooms at a
time, as there are often a lot of really tiny rooms, which can massively
slow things down.