Just after a task acquires a contended `Linearizer` lock, it sleeps.
If the task is cancelled during this sleep, we need to release the lock.
Signed-off-by: Sean Quah <seanq@element.io>
Refactor and convert `Linearizer` to async. This makes a `Linearizer`
cancellation bug easier to fix.
Also refactor to use an async context manager, which eliminates an
unlikely footgun where code that doesn't immediately use the context
manager could forget to release the lock.
Signed-off-by: Sean Quah <seanq@element.io>
These decorators mostly support cancellation already. Add cancellation
tests and fix use of finished logging contexts by delaying cancellation,
as suggested by @erikjohnston.
Signed-off-by: Sean Quah <seanq@element.io>
`delay_cancellation` behaves like `stop_cancellation`, except it
delays `CancelledError`s until the original `Deferred` resolves.
This is handy for unifying cleanup paths and ensuring that uncancelled
coroutines don't use finished logcontexts.
Signed-off-by: Sean Quah <seanq@element.io>
* `@cached` can now take an `uncached_args` which is an iterable of names to not use in the cache key.
* Requires `@cached`, @cachedList` and `@lru_cache` to use keyword arguments for clarity.
* Asserts that keyword-only arguments in cached functions are not accepted. (I tested this briefly and I don't believe this works properly.)
* Fix incorrect argument in test case
* Add copyright header
* Docstring and __all__
* Exclude dev depenencies
* Use changelog from #12088
* Include version in error messages
This will hopefully distinguish between the version of the source code
and the version of the distribution package that is installed.
* Linter script is your friend
* Pull runtime dep checks into their own module
* Reimplement `check_requirements` using `importlib`
I've tried to make this clearer. We start by working out which of
Synapse's requirements we need to be installed here and now. I was
surprised that there wasn't an easier way to see which packages were
installed by a given extra.
I've pulled out the error messages into functions that deal with "is
this for an extra or not". And I've rearranged the loop over two
different sets of requirements into one loop with a "must be instaled"
flag.
I hope you agree that this is clearer.
* Test cases
* Fix 'Unhandled error in Deferred'
Fixes a CRITICAL "Unhandled error in Deferred" log message which happened when
a function wrapped with `@cachedList` failed
* Minor optimisation to cachedListDescriptor
we can avoid re-using `missing`, which saves looking up entries in
`deferreds_map`, and means we don't need to copy it.
* Improve type annotation on CachedListDescriptor
* fix incorrect unwrapFirstError import
this was being imported from the wrong place
* Refactor `concurrently_execute` to use `yieldable_gather_results`
* Improve exception handling in `yieldable_gather_results`
Try to avoid swallowing so many stack traces.
* mark unwrapFirstError deprecated
* changelog
Part of the Tchap Synapse mainlining.
This allows modules to implement extra logic to figure out whether a given 3PID can be added to the local homeserver. In the Tchap use case, this will allow a Synapse module to interface with the custom endpoint /internal_info.
This adds some opentracing annotations to ResponseCache, to make it easier to see what's going on; in particular, it adds a link back to the initial trace which is actually doing the work of generating the response.
When all entries in an `LruCache` have a size of 0 according to the
provided `size_callback`, and `drop_from_cache` is called on a cache
node, the node would be unlinked from the LRU linked list but remain in
the cache dictionary. An assertion would be later be tripped due to the
inconsistency.
Avoid unintentionally calling `__len__` and use a strict `is None`
check instead when unwrapping the weak reference.
Updating mypy past version 0.9 means that third-party stubs are no-longer distributed with typeshed. See http://mypy-lang.blogspot.com/2021/06/mypy-0900-released.html for details.
We therefore pull in stub packages in setup.py
Additionally, some modules that we were previously ignoring import failures for now have stubs. So let's use them.
The rest of this change consists of fixups to make the newer mypy + stubs pass CI.
Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>
Use `PreserveLoggingContext()` to ensure that logging contexts are not
lost when exiting a read/write lock.
When exiting a read/write lock, callbacks on a `Deferred` are triggered
as a signal to any waiting coroutines. Any waiting coroutine that
becomes runnable is likely to follow the Synapse logging context rules
and will restore its own logging context, then either run to completion
or await another `Deferred`, resetting the logging context in the
process.
The following modules now pass `disallow_untyped_defs`:
* synapse.util.caches.cached_call
* synapse.util.caches.lrucache
* synapse.util.caches.response_cache
* synapse.util.caches.stream_change_cache
* synapse.util.caches.ttlcache pass
* synapse.util.daemonize
* synapse.util.patch_inline_callbacks pass `no-untyped-defs`
* synapse.util.versionstring
Additional typing in synapse.util.metrics. Didn't get this to pass `no-untyped-defs`, think I'll need to watch #10847
Currently we use `JsonEncoder.iterencode` to write JSON responses, which ensures that we don't block the main reactor thread when encoding huge objects. The downside to this is that `iterencode` falls back to using a pure Python encoder that is *much* less efficient and can easily burn a lot of CPU for huge responses. To fix this, while still ensuring we don't block the reactor loop, we encode the JSON on a threadpool using the standard `JsonEncoder.encode` functions, which is backed by a C library.
Doing so, however, requires `respond_with_json` to have access to the reactor, which it previously didn't. There are two ways of doing this:
1. threading through the reactor object, which is a bit fiddly as e.g. `DirectServeJsonResource` doesn't currently take a reactor, but is exposed to modules and so is a PITA to change; or
2. expose the reactor in `SynapseRequest`, which requires updating a bunch of servlet types.
I went with the latter as that is just a mechanical change, and I think makes sense as a request already has a reactor associated with it (via its http channel).
Instead of wrapping the JSON into an object, this creates concrete
instances for Transaction and Edu. This allows for improved type
hints and simplified code.
Mostly this involves decorating a few Deferred declarations with extra type hints. We wrap the types in quotes to avoid runtime errors when running against older versions of Twisted that don't have generics on Deferred.
This PR adds a common configuration section for all modules (see docs). These modules are then loaded at startup by the homeserver. Modules register their hooks and web resources using the new `register_[...]_callbacks` and `register_web_resource` methods of the module API.
This is the first of two PRs which seek to address #8518. This first PR lays the groundwork by extending ResponseCache; a second PR (#10158) will update the SyncHandler to actually use it, and fix the bug.
The idea here is that we allow the callback given to ResponseCache.wrap to decide whether its result should be cached or not. We do that by (optionally) passing a ResponseCacheContext into it, which it can modify.
* Make `invalidate` and `invalidate_many` do the same thing
... so that we can do either over the invalidation replication stream, and also
because they always confused me a bit.
* Kill off `invalidate_many`
* changelog
`keylen` seems to be a thing that is frequently incorrectly set, and we don't really need it.
The only time it was used was to figure out if we had removed a subtree in `del_multi`, which we can do better by changing `TreeCache.pop` to return a different type (`TreeCacheNode`).
Commits should be independently reviewable.
- use a tuple rather than a list for the iterable that is passed into the
wrapped function, for performance
- test that we can pass an iterable and that keys are correctly deduped.
We can get away with just catching UnicodeError here.
⋮
+-- ValueError
| +-- UnicodeError
| +-- UnicodeDecodeError
| +-- UnicodeEncodeError
| +-- UnicodeTranslateError
⋮
https://docs.python.org/3/library/exceptions.html#exception-hierarchy
Signed-off-by: Dan Callahan <danc@element.io>
Functionally identical, but more obviously cryptographically secure.
...Explicit is better than implicit?
Avoids needing to know that SystemRandom() implies a CSPRNG, and
complies with the big scary red box on the documentation for random:
> Warning:
> The pseudo-random generators of this module should not be used for
> security purposes. For security or cryptographic uses, see the
> secrets module.
https://docs.python.org/3/library/random.html
Signed-off-by: Dan Callahan <danc@element.io>
* tests for push rule pattern matching
* tests for acl pattern matching
* factor out common `re.escape`
* Factor out common re.compile
* Factor out common anchoring code
* add word_boundary support to `glob_to_regex`
* Use `glob_to_regex` in push rule evaluator
NB that this drops support for character classes. I don't think anyone ever
used them.
* Improve efficiency of globs with multiple wildcards
The idea here is that we compress multiple `*` globs into a single `.*`. We
also need to consider `?`, since `*?*` is as hard to implement efficiently as
`**`.
* add assertion on regex pattern
* Fix mypy
* Simplify glob_to_regex
* Inline the glob_to_regex helper function
Signed-off-by: Dan Callahan <danc@element.io>
* Moar comments
Signed-off-by: Dan Callahan <danc@element.io>
Co-authored-by: Dan Callahan <danc@element.io>
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+.
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).
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>`
Running `dmypy run` will do a `mypy` check while spinning up a daemon
that makes rerunning `dmypy run` a lot faster.
`dmypy` doesn't support `follow_imports = silent` and has
`local_partial_types` enabled, so this PR enables those options and
fixes the issues that were newly raised. Note that `local_partial_types`
will be enabled by default in upcoming mypy releases.