This improves type hinting and should use less memory.

This was never used, so let's get rid of it.

Pusher URLs now must end in `/_matrix/push/v1/notify` per the
specification.

Replaces the `federation_ip_range_blacklist` configuration setting with an
`ip_range_blacklist` setting with wider scope. It now applies to:

* Federation
* Identity servers
* Push notifications
* Checking key validitity for third-party invite events

The old `federation_ip_range_blacklist` setting is still honored if present, but
with reduced scope (it only applies to federation and identity servers).

Add a config option to change whether unread push notification counts are per-message or per-room (#8820)

This PR adds a new config option to the `push` section of the homeserver config, `group_unread_count_by_room`. By default Synapse will group push notifications by room (so if you have 1000 unread messages, if they lie in 55 rooms, you'll see an unread count on your phone of 55).

However, it is also useful to be able to send out the true count of unread messages if desired. If `group_unread_count_by_room` is set to `false`, then with the above example, one would see an unread count of 1000 (email anyone?).

We do it this way round so that only the "owner" can delete the access token (i.e. `/logout/all` by the "owner" also deletes that token, but `/logout/all` by the "target user" doesn't).

A future PR will add an API for creating such a token.

When the target user and authenticated entity are different the `Processed request` log line will be logged with a: `{@admin:server as @bob:server} ...`. I'm not convinced by that format (especially since it adds spaces in there, making it harder to use `cut -d ' '` to chop off the start of log lines). Suggestions welcome.

This can happen if e.g. the room invited into is no longer on the
server (or if all users left the room).

* Fix spec compliance; tweaks without values are valid

(default to True, which is only concretely specified for
`highlight`, but it seems only reasonable to generalise)

* Changelog for 7766.

* Add documentation to `tweaks_for_actions`

May as well tidy up when I'm here.

* Add a test for `tweaks_for_actions`

* Remove obsolete comment about ancient temporary code

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

* Implement hack to set push priority

based on whether the tweaks indicate the event might cause
effects.

* Changelog for 7765

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

* Antilint

* Add tests for push priority

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

* Update synapse/push/httppusher.py

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

* Antilint

* Remove needless invites from tests.

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

Ensure good comprehension hygiene using flake8-comprehensions.

* Remove redundant python2 support code

`str.decode()` doesn't exist on python3, so presumably this code was doing
nothing

* Filter out pushers with corrupt data

When we get a row with unparsable json, drop the row, rather than returning a
row with null `data`, which will then cause an explosion later on.

* Improve logging when we can't start a pusher

Log the ID to help us understand the problem

* Make email pusher setup more robust

We know we'll have a `data` member, since that comes from the database. What we
*don't* know is if that is a dict, and if that has a `brand` member, and if
that member is a string.

The `http_proxy` and `HTTPS_PROXY` env vars can be set to a `host[:port]` value which should point to a proxy.

The address of the proxy should be excluded from IP blacklists such as the `url_preview_ip_range_blacklist`.

The proxy will then be used for
 * push
 * url previews
 * phone-home stats
 * recaptcha validation
 * CAS auth validation

It will *not* be used for:
 * Application Services
 * Identity servers
 * Outbound federation
 * In worker configurations, connections from workers to masters

Fixes #4198.

Migrate all tests to use the dict-based config format instead of hanging items off HomeserverConfig (#5171)

It doesn't really belong under rest/client/v1 any more.

The Mailer expects the config object to have `email_smtp_pass` and
`email_riot_base_url` attributes (and it won't by default, because the default
config impl doesn't set any of the attributes unless email_enable_notifs is
set).