Add Application Service registration type requirement + py35, pg95 deprecation notices to v1.32.0 upgrade notes (#9849)

Fixes https://github.com/matrix-org/synapse/issues/9846.

Adds important removal information from the top of https://github.com/matrix-org/synapse/releases/tag/v1.32.0rc1 into UPGRADE.rst.

As far as I can tell our logging contexts are meant to log the request ID, or sometimes the request ID followed by a suffix (this is generally stored in the name field of LoggingContext). There's also code to log the name@memory location, but I'm not sure this is ever used.

This simplifies the code paths to require every logging context to have a name and use that in logging. For sub-contexts (created via nested_logging_contexts, defer_to_threadpool, Measure) we use the current context's str (which becomes their name or the string "sentinel") and then potentially modify that (e.g. add a suffix).

Port "Allow users to click account renewal links multiple times without hitting an 'Invalid Token' page #74" from synapse-dinsic (#9832)

This attempts to be a direct port of https://github.com/matrix-org/synapse-dinsic/pull/74 to mainline. There was some fiddling required to deal with the changes that have been made to mainline since (mainly dealing with the split of `RegistrationWorkerStore` from `RegistrationStore`, and the changes made to `self.make_request` in test code).

Signed-off-by: Denis Kasak <dkasak@termina.org.uk>

Fixes: #9797.

Should help reduce CPU usage on the user directory, especially when memberships change in rooms with lots of state history.

There are a couple of points in `persist_events` where we are doing a
query per event in series, which we can replace.

Every single time I want to access the config object, I have to remember
whether or not we use `get_config`. Let's just get rid of it.

This refactoring allows adding logic that uses the event context
before persisting it.

This reverts commit cc51aaaa.

The PR was prematurely merged and not yet approved.

When receiving a /send_join request for a room with join rules set to 'restricted',
check if the user is a member of the spaces defined in the 'allow' key of the join
rules.
    
This only applies to an experimental room version, as defined in MSC3083.

This basically speeds up federation by "squeezing" each individual dual database call (to destinations and destination_rooms), which previously happened per every event, into one call for an entire batch (100 max).

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

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

Signed-off-by: Sergey Shpikin <rkfg@rkfg.me>

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;`>

This PR adds a Dockerfile and some supporting files to the `docker/` directory. The Dockerfile's intention is to spin up a container with:

* A Synapse main process.
* Any desired worker processes, defined by a `SYNAPSE_WORKERS` environment variable supplied at runtime.
* A redis for worker communication.
* A nginx for routing traffic.
* A supervisord to start all worker processes and monitor them if any go down.

Note that **this is not currently intended to be used in production**. If you'd like to use Synapse workers with Docker, instead make use of the official image, with one worker per container. The purpose of this dockerfile is currently to allow testing Synapse in worker mode with the [Complement](https://github.com/matrix-org/complement/) test suite.

`configure_workers_and_start.py` is where most of the magic happens in this PR. It reads from environment variables (documented in the file) and creates all necessary config files for the processes. It is the entrypoint of the Dockerfile, and thus is run any time the docker container is spun up, recreating all config files in case you want to use a different set of workers. One can specify which workers they'd like to use by setting the `SYNAPSE_WORKERS` environment variable (as a comma-separated list of arbitrary worker names) or by setting it to `*` for all worker processes. We will be using the latter in CI.

Huge thanks to @MatMaul for helping get this all working  This PR is paired with its equivalent on the Complement side: https://github.com/matrix-org/complement/pull/62.

Note, for the purpose of testing this PR before it's merged: You'll need to (re)build the base Synapse docker image for everything to work (`matrixdotorg/synapse:latest`). Then build the worker-based docker image on top (`matrixdotorg/synapse:workers`). 

Context is in https://github.com/matrix-org/synapse/issues/9764#issuecomment-818615894.

I struggled to find a more official link for this. The problem occurs when using WSL1 instead of WSL2, which some Windows platforms (at least Server 2019) still don't have. Docker have updated their documentation to paint a much happier picture now given WSL2's support.

The last sentence here can probably be removed once WSL1 is no longer around... though that will likely not be for a very long time.

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Signed-off-by: Dan Callahan <danc@element.io>

* Drop Python 3.5 from Trove classifier metadata.

Signed-off-by: Dan Callahan <danc@element.io>

Signed-off-by: Dan Callahan <danc@element.io>

This change ensures that the appservice registration behaviour follows the spec. We decided to do this for Dendrite, so it made sense to also make a PR for synapse to correct the behaviour.

There's no point logging this twice.

By providing the additional build tag for `msc2946`.