def run(*args: P.args, **kwargs: P.kwargs) -> Awaitable[R]:
# Assertion required because mypy can't prove we won't change `f`
# back to `None`. See
# https://mypy.readthedocs.io/en/latest/common_issues.html#narrowing-and-inner-functions
assert f is not None
return maybe_awaitable(f(*args, **kwargs))
def looping_background_call(
self,
f: Callable,
msec: float,
*args: object,
desc: Optional[str] = None,
run_on_all_instances: bool = False,
**kwargs: object,
) -> None:
"""Wraps a function as a background process and calls it repeatedly.
NOTE: Will only run on the instance that is configured to run
background processes (which is the main process by default), unless
`run_on_all_workers` is set.
Waits `msec` initially before calling `f` for the first time.
Added in Synapse v1.39.0.
Args:
f: The function to call repeatedly. f can be either synchronous or
asynchronous, and must follow Synapse's logcontext rules.
More info about logcontexts is available at
https://matrix-org.github.io/synapse/latest/log_contexts.html
msec: How long to wait between calls in milliseconds.
*args: Positional arguments to pass to function.
desc: The background task's description. Default to the function's name.
run_on_all_instances: Whether to run this on all instances, rather
than just the instance configured to run background tasks.
**kwargs: Key arguments to pass to function.
"""
if desc is None:
desc = f.__name__
if self._hs.config.worker.run_background_tasks or run_on_all_instances:
self._clock.looping_call(
run_as_background_process,
msec,
desc,
lambda: maybe_awaitable(f(*args, **kwargs)),
)
else:
logger.warning(
"Not running looping call %s as the configuration forbids it",
f,
)
def run(*args, **kwargs):
# mypy doesn't do well across function boundaries so we need to tell it
# f is definitely not None.
assert f is not None
return maybe_awaitable(f(*args, **kwargs))