mirror of
https://pagure.io/fm-orchestrator.git
synced 2026-04-24 18:52:25 +08:00
f8079308b1
To support multiple backend, we need to get rid of `further_work` concept which is used in multiple places in the MBS code. Before this commit, if one handler wanted to execute another handler, it planned this work by constructing fake message and returning it. MBSConsumer then planned its execution by adding it into the event loop. In this commit, the new `events.scheduler` instance of new Scheduler class is used to acomplish this. If handler wants to execute another handler, it simply schedules it using `events.scheduler.add` method. In the end of each handler, the `events.scheduler.run` method is executed which calls all the scheduled handlers. The idea is that when Celery is enabled, we can change the `Scheduler.run` method to execute the handlers using the Celery, while during the local builds, we could execute them directly without Celery. Use of Scheduler also fixes the issue with ordering of such calls. If we would call the handlers directly, they could have been executed in the middle of another handler leading to behavior incompatible with the current `further_work` concept. Using the Scheduler, these calls are executed always in the end of the handler no matter when they have been scheduled.
88 lines
2.6 KiB
Python
88 lines
2.6 KiB
Python
# -*- coding: utf-8 -*-
|
|
# SPDX-License-Identifier: MIT
|
|
|
|
"""
|
|
This module defines constant for events emitted by external services that work
|
|
with MBS together to complete a module build.
|
|
|
|
The event name is defined in general as much as possible, especially for the
|
|
events from Koji. Because some instance based on Koji, like Brew, might send
|
|
messages to different topics on different message bus. For example, when a
|
|
build is complete, Koji sends a message to topic buildsys.build.state.change,
|
|
however Brew sends to topic brew.build.complete, etc.
|
|
"""
|
|
|
|
import time
|
|
import sched
|
|
from functools import wraps
|
|
|
|
from module_build_service import log
|
|
|
|
|
|
KOJI_BUILD_CHANGE = "koji_build_change"
|
|
KOJI_TAG_CHANGE = "koji_tag_change"
|
|
KOJI_REPO_CHANGE = "koji_repo_change"
|
|
MBS_MODULE_STATE_CHANGE = "mbs_module_state_change"
|
|
GREENWAVE_DECISION_UPDATE = "greenwave_decision_update"
|
|
|
|
|
|
class Scheduler(sched.scheduler):
|
|
"""
|
|
Subclass of `sched.scheduler` allowing to schedule handlers calls.
|
|
|
|
If one of the MBS handler functions need to call another handler, they need to do it in a safe
|
|
way - such another handler call should not be done in the middle of another handler's
|
|
execution.
|
|
|
|
This class provides an solution for that. Handler can schedule run of other handler using
|
|
the `add` method. The handlers should use `mbs_event_handler` decorator which ensures that
|
|
the `run` method is called at the end of handler's execution and other scheduler handlers
|
|
are executed.
|
|
"""
|
|
|
|
def add(self, handler, arguments=()):
|
|
"""
|
|
Schedule execution of `handler` with `arguments`.
|
|
"""
|
|
self.enter(0, 0, handler, arguments)
|
|
|
|
def run(self):
|
|
"""
|
|
Runs scheduled handlers.
|
|
"""
|
|
log.debug("Running event scheduler with following events:")
|
|
for event in self.queue:
|
|
log.debug(" %r", event)
|
|
sched.scheduler.run(self)
|
|
|
|
def reset(self):
|
|
"""
|
|
Resets the Scheduler to initial state.
|
|
"""
|
|
while not self.empty():
|
|
self.cancel(self.queue[0])
|
|
|
|
|
|
scheduler = Scheduler(time.time, delayfunc=lambda x: x)
|
|
|
|
|
|
def mbs_event_handler():
|
|
"""
|
|
A decorator for MBS event handlers. It implements common tasks which should otherwise
|
|
be repeated in every MBS event handler, for example:
|
|
|
|
- at the end of handler, call events.scheduler.run().
|
|
"""
|
|
|
|
def decorator(func):
|
|
@wraps(func)
|
|
def wrapper(*args, **kwargs):
|
|
try:
|
|
return func(*args, **kwargs)
|
|
finally:
|
|
scheduler.run()
|
|
|
|
return wrapper
|
|
|
|
return decorator
|