138 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			138 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			Python
		
	
	
| # -*- coding: utf-8 -*-
 | |
| # Copyright 2014-2016 OpenMarket Ltd
 | |
| #
 | |
| # Licensed under the Apache License, Version 2.0 (the "License");
 | |
| # you may not use this file except in compliance with the License.
 | |
| # You may obtain a copy of the License at
 | |
| #
 | |
| #     http://www.apache.org/licenses/LICENSE-2.0
 | |
| #
 | |
| # Unless required by applicable law or agreed to in writing, software
 | |
| # distributed under the License is distributed on an "AS IS" BASIS,
 | |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 | |
| # See the License for the specific language governing permissions and
 | |
| # limitations under the License.
 | |
| 
 | |
| from synapse.api.errors import SynapseError
 | |
| from synapse.util.logcontext import PreserveLoggingContext
 | |
| 
 | |
| from twisted.internet import defer, reactor, task
 | |
| 
 | |
| import time
 | |
| import logging
 | |
| 
 | |
| logger = logging.getLogger(__name__)
 | |
| 
 | |
| 
 | |
| class DeferredTimedOutError(SynapseError):
 | |
|     def __init__(self):
 | |
|         super(DeferredTimedOutError, self).__init__(504, "Timed out")
 | |
| 
 | |
| 
 | |
| def unwrapFirstError(failure):
 | |
|     # defer.gatherResults and DeferredLists wrap failures.
 | |
|     failure.trap(defer.FirstError)
 | |
|     return failure.value.subFailure
 | |
| 
 | |
| 
 | |
| class Clock(object):
 | |
|     """A small utility that obtains current time-of-day so that time may be
 | |
|     mocked during unit-tests.
 | |
| 
 | |
|     TODO(paul): Also move the sleep() functionality into it
 | |
|     """
 | |
| 
 | |
|     def time(self):
 | |
|         """Returns the current system time in seconds since epoch."""
 | |
|         return time.time()
 | |
| 
 | |
|     def time_msec(self):
 | |
|         """Returns the current system time in miliseconds since epoch."""
 | |
|         return int(self.time() * 1000)
 | |
| 
 | |
|     def looping_call(self, f, msec):
 | |
|         """Call a function repeatedly.
 | |
| 
 | |
|          Waits `msec` initially before calling `f` for the first time.
 | |
| 
 | |
|         Args:
 | |
|             f(function): The function to call repeatedly.
 | |
|             msec(float): How long to wait between calls in milliseconds.
 | |
|         """
 | |
|         l = task.LoopingCall(f)
 | |
|         l.start(msec / 1000.0, now=False)
 | |
|         return l
 | |
| 
 | |
|     def call_later(self, delay, callback, *args, **kwargs):
 | |
|         """Call something later
 | |
| 
 | |
|         Args:
 | |
|             delay(float): How long to wait in seconds.
 | |
|             callback(function): Function to call
 | |
|             *args: Postional arguments to pass to function.
 | |
|             **kwargs: Key arguments to pass to function.
 | |
|         """
 | |
|         def wrapped_callback(*args, **kwargs):
 | |
|             with PreserveLoggingContext():
 | |
|                 callback(*args, **kwargs)
 | |
| 
 | |
|         with PreserveLoggingContext():
 | |
|             return reactor.callLater(delay, wrapped_callback, *args, **kwargs)
 | |
| 
 | |
|     def cancel_call_later(self, timer, ignore_errs=False):
 | |
|         try:
 | |
|             timer.cancel()
 | |
|         except:
 | |
|             if not ignore_errs:
 | |
|                 raise
 | |
| 
 | |
|     def time_bound_deferred(self, given_deferred, time_out):
 | |
|         if given_deferred.called:
 | |
|             return given_deferred
 | |
| 
 | |
|         ret_deferred = defer.Deferred()
 | |
| 
 | |
|         def timed_out_fn():
 | |
|             e = DeferredTimedOutError()
 | |
| 
 | |
|             try:
 | |
|                 ret_deferred.errback(e)
 | |
|             except:
 | |
|                 pass
 | |
| 
 | |
|             try:
 | |
|                 given_deferred.cancel()
 | |
|             except:
 | |
|                 pass
 | |
| 
 | |
|         timer = None
 | |
| 
 | |
|         def cancel(res):
 | |
|             try:
 | |
|                 self.cancel_call_later(timer)
 | |
|             except:
 | |
|                 pass
 | |
|             return res
 | |
| 
 | |
|         ret_deferred.addBoth(cancel)
 | |
| 
 | |
|         def success(res):
 | |
|             try:
 | |
|                 ret_deferred.callback(res)
 | |
|             except:
 | |
|                 pass
 | |
| 
 | |
|             return res
 | |
| 
 | |
|         def err(res):
 | |
|             try:
 | |
|                 ret_deferred.errback(res)
 | |
|             except:
 | |
|                 pass
 | |
| 
 | |
|         given_deferred.addCallbacks(callback=success, errback=err)
 | |
| 
 | |
|         timer = self.call_later(time_out, timed_out_fn)
 | |
| 
 | |
|         return ret_deferred
 |