Introduce `Clock.call_when_running(...)` to wrap startup code in a
logcontext, ensuring we can identify which server generated the logs.
Background:
> Ideally, nothing from the Synapse homeserver would be logged against the `sentinel`
> logcontext as we want to know which server the logs came from. In practice, this is not
> always the case yet especially outside of request handling.
>
> Global things outside of Synapse (e.g. Twisted reactor code) should run in the
> `sentinel` logcontext. It's only when it calls into application code that a logcontext
> gets activated. This means the reactor should be started in the `sentinel` logcontext,
> and any time an awaitable yields control back to the reactor, it should reset the
> logcontext to be the `sentinel` logcontext. This is important to avoid leaking the
> current logcontext to the reactor (which would then get picked up and associated with
> the next thing the reactor does).
>
> *-- `docs/log_contexts.md`
Also adds a lint to prefer `Clock.call_when_running(...)` over
`reactor.callWhenRunning(...)`
Part of https://github.com/element-hq/synapse/issues/18905
Bulk refactor `Histogram` metrics to be homeserver-scoped. We also add
lints to make sure that new `Histogram` metrics don't sneak in without
using the `server_name` label (`SERVER_NAME_LABEL`).
Part of https://github.com/element-hq/synapse/issues/18592
### Testing strategy
1. Add the `metrics` listener in your `homeserver.yaml`
```yaml
listeners:
# This is just showing how to configure metrics either way
#
# `http` `metrics` resource
- port: 9322
type: http
bind_addresses: ['127.0.0.1']
resources:
- names: [metrics]
compress: false
# `metrics` listener
- port: 9323
type: metrics
bind_addresses: ['127.0.0.1']
```
1. Start the homeserver: `poetry run synapse_homeserver --config-path
homeserver.yaml`
1. Fetch `http://localhost:9322/_synapse/metrics` and/or
`http://localhost:9323/metrics`
1. Observe response includes the TODO metrics with the `server_name`
label
### Todo
- [x] Wait for https://github.com/element-hq/synapse/pull/18656 to merge
### Dev notes
```
LoggingDatabaseConnection
make_conn
make_pool
make_fake_db_pool
```
### Pull Request Checklist
<!-- Please read
https://element-hq.github.io/synapse/latest/development/contributing_guide.html
before submitting your pull request -->
* [x] Pull request is based on the develop branch
* [x] Pull request includes a [changelog
file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog).
The entry should:
- Be a short description of your change which makes sense to users.
"Fixed a bug that prevented receiving messages from other servers."
instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
- Use markdown where necessary, mostly for `code blocks`.
- End with either a period (.) or an exclamation mark (!).
- Start with a capital letter.
- Feel free to credit yourself, by adding a sentence "Contributed by
@github_username." or "Contributed by [Your Name]." to the end of the
entry.
* [x] [Code
style](https://element-hq.github.io/synapse/latest/code_style.html) is
correct (run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))
During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.
Switching to a sequence means there's no need to track `last_txn` on the
AS state table to generate new TXN IDs. This also means that there is
no longer contention between the AS scheduler and AS handler on updates
to the `application_services_state` table, which will prevent serialization
errors during the complete AS txn transaction.
This removes the magic allowing accessing configurable
variables directly from the config object. It is now required
that a specific configuration class is used (e.g. `config.foo`
must be replaced with `config.server.foo`).
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.
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>`
This is so we can tell what is going on when things are taking a while to start up.
The main change here is to ensure that transactions that are created during startup get correctly logged like normal transactions.
Doing this I learned e.message was pretty shortlived, added in 2.6,
they realized it was a bad idea and deprecated it in 2.7
Signed-off-by: Adrian Tschira <nota@notafile.com>
