mirror of https://github.com/m-labs/artiq.git
52 lines
1.9 KiB
Python
52 lines
1.9 KiB
Python
import threading
|
|
import logging
|
|
import inspect
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class FFProxy:
|
|
"""Proxies a target object and runs its methods in the background.
|
|
|
|
All method calls to this object are forwarded to the target and executed
|
|
in a background thread. Method calls return immediately. Exceptions from
|
|
the target method are turned into warnings. At most one method from the
|
|
target object may be executed in the background; if a new call is
|
|
submitted while the previous one is still executing, a warning is printed
|
|
and the new call is dropped.
|
|
|
|
This feature is typically used to wrap slow and non-critical RPCs in
|
|
experiments.
|
|
"""
|
|
def __init__(self, target):
|
|
self.target = target
|
|
|
|
valid_methods = inspect.getmembers(target, inspect.ismethod)
|
|
self._valid_methods = {m[0] for m in valid_methods}
|
|
self._thread = None
|
|
|
|
def ff_join(self):
|
|
"""Waits until any background method finishes its execution."""
|
|
if self._thread is not None:
|
|
self._thread.join()
|
|
|
|
def __getattr__(self, k):
|
|
if k not in self._valid_methods:
|
|
raise AttributeError
|
|
def run_in_thread(*args, **kwargs):
|
|
if self._thread is not None and self._thread.is_alive():
|
|
logger.warning("skipping fire-and-forget call to %r.%s as "
|
|
"previous call did not complete",
|
|
self.target, k)
|
|
return
|
|
def thread_body():
|
|
try:
|
|
getattr(self.target, k)(*args, **kwargs)
|
|
except:
|
|
logger.warning("fire-and-forget call to %r.%s raised an "
|
|
"exception:", self.target, k, exc_info=True)
|
|
self._thread = threading.Thread(target=thread_body)
|
|
self._thread.start()
|
|
return run_in_thread
|