def exit(self, result=None):
self._cleanup()
if not self._is_root:
# If not a root section just return the result as-is
return result
# We are a root sections
if IFiber.providedBy(result):
# If the result is a fiber, we initialize and start it
fiber = IFiber(result)
self.descriptor.attach(fiber)
return fiber.start()
if isinstance(result, defer.Deferred):
return result
elif isinstance(result, failure.Failure):
return defer.fail(result)
else:
return defer.succeed(result)
def maybe_fiber(_function, *args, **kwargs):
try:
result = _function(*args, **kwargs)
except Exception:
return defer.fail(failure.Failure())
else:
if IFiber.providedBy(result):
return result.start()
if isinstance(result, defer.Deferred):
return result
elif isinstance(result, failure.Failure):
return defer.fail(result)
else:
return defer.succeed(result)
def maybeDeferred(f, *args, **kw):
"""
Copied from twsited.internet.defer and add a check to detect fibers.
"""
try:
result = f(*args, **kw)
except Exception:
return fail(failure.Failure())
if IFiber.providedBy(result):
import traceback
frames = traceback.extract_stack()
msg = "%s returned a fiber instead of a deferred" % (f, )
if len(frames) > 1:
msg += "; called from %s" % (frames[-2], )
raise RuntimeError(msg)
if isinstance(result, Deferred):
return result
elif isinstance(result, failure.Failure):
return fail(result)
else:
return succeed(result)
def attach(self, fiber):
fiber = IFiber(fiber)
fiber._bind(self, self.fiber_id, 1)
def _check_side_effet_result(result, info):
if isinstance(result, defer.Deferred):
raise SideEffectResultError("Side-effect functions %s " "cannot return Deferred" % info)
if IFiber.providedBy(result):
raise SideEffectResultError("Side-effect functions %s " "cannot return IFiber" % info)
return result
