def run(self):
with fasteners.try_lock(self._lock) as was_locked:
if not was_locked:
raise exc.ExecutionFailure("Engine currently locked, please"
" try again later")
for _state in self.run_iter():
pass
def run(self, timeout=None):
"""Runs the engine (or die trying).
:param timeout: timeout to wait for any atoms to complete (this timeout
will be used during the waiting period that occurs when
unfinished atoms are being waited on).
"""
with fasteners.try_lock(self._lock) as was_locked:
if not was_locked:
raise exc.ExecutionFailure("Engine currently locked, please"
" try again later")
for _state in self.run_iter(timeout=timeout):
pass
def _schedule_task(self, task):
"""Schedules the given task atom for *future* completion.
Depending on the atoms stored intention this may schedule the task
atom for reversion or execution.
"""
intention = self._storage.get_atom_intention(task.name)
if intention == st.EXECUTE:
return self._task_action.schedule_execution(task)
elif intention == st.REVERT:
return self._task_action.schedule_reversion(task)
else:
raise excp.ExecutionFailure("Unknown how to schedule task with"
" intention: %s" % intention)
def _schedule_retry(self, retry):
"""Schedules the given retry atom for *future* completion.
Depending on the atoms stored intention this may schedule the retry
atom for reversion or execution.
"""
intention = self._storage.get_atom_intention(retry.name)
if intention == st.EXECUTE:
return self._retry_action.execute(retry)
elif intention == st.REVERT:
return self._retry_action.revert(retry)
elif intention == st.RETRY:
self._retry_action.change_state(retry, st.RETRYING)
_retry_subflow(retry, self._runtime)
return self._retry_action.execute(retry)
else:
raise excp.ExecutionFailure("Unknown how to schedule retry with"
" intention: %s" % intention)
def schedule(self, retry):
"""Schedules the given retry atom for *future* completion.
Depending on the atoms stored intention this may schedule the retry
atom for reversion or execution.
"""
intention = self._storage.get_atom_intention(retry.name)
if intention == st.EXECUTE:
return self._retry_action.schedule_execution(retry)
elif intention == st.REVERT:
return self._retry_action.schedule_reversion(retry)
elif intention == st.RETRY:
self._retry_action.change_state(retry, st.RETRYING)
# This will force the subflow to start processing right *after*
# this retry atom executes (since they will be blocked on their
# predecessor getting out of the RETRYING/RUNNING state).
self._runtime.retry_subflow(retry)
return self._retry_action.schedule_execution(retry)
else:
raise excp.ExecutionFailure("Unknown how to schedule retry with"
" intention: %s" % intention)
def execute(self, **kwargs):
raise exceptions.ExecutionFailure("We want to force a revert here")