From: Michael Tremer <michael.tremer@ipfire.org>
Date: Mon, 18 Jul 2022 16:17:38 +0000 (+0000)
Subject: backend: Move running background tasks into backend
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=fcffdb60279a8110d6b1a40b6fae0de229a941b9;p=pbs.git

backend: Move running background tasks into backend

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/buildservice/__init__.py b/src/buildservice/__init__.py
index 925b1321..dbe7e568 100644
--- a/src/buildservice/__init__.py
+++ b/src/buildservice/__init__.py
@@ -2,6 +2,7 @@
 
 import asyncio
 import configparser
+import inspect
 import logging
 import os
 import pakfire
@@ -44,6 +45,9 @@ from .constants import *
 class Backend(object):
 	version = __version__
 
+	# A list of any background tasks
+	__tasks = set()
+
 	def __init__(self, config_file=None):
 		# Read configuration file.
 		self.config = self.read_config(config_file)
@@ -161,6 +165,48 @@ class Backend(object):
 			# Delete the configuration file
 			os.unlink(t)
 
+	# Functions to run something in background
+
+	def run_task(self, callback, *args):
+		"""
+			Runs the given coroutine in the background
+		"""
+		# Create a new task
+		task = asyncio.create_task(callback(*args))
+
+		# Keep a reference to the task and remove it when the task has finished
+		self.__tasks.add(task)
+		task.add_done_callback(self.__tasks.discard)
+
+		return task
+
+	def run_periodic_task(self, delay, callback, *args):
+		"""
+			Calls the given callback periodically in the background
+		"""
+		self.run_task(self._periodic_task, delay, callback, *args)
+
+	async def _periodic_task(self, delay, callback, *args):
+		"""
+			Helper function for run_periodic_task() that will call the given
+			callback regulary after the timer has expired.
+		"""
+		log.debug("Periodic callback %r started" % callback)
+
+		while True:
+			# Wait a little moment
+			await asyncio.sleep(delay)
+
+			try:
+				ret = callback(*args)
+
+				# Await ret if callback is a coroutine
+				if inspect.isawaitable(ret):
+					await ret
+
+			except Exception as e:
+				log.error("Exception in periodic callback %r" % callback, exc_info=True)
+
 	# Commands
 
 	async def command(self, *args, krb5_auth=False, **kwargs):
diff --git a/src/hub/__init__.py b/src/hub/__init__.py
index 6184406f..d8291d9d 100644
--- a/src/hub/__init__.py
+++ b/src/hub/__init__.py
@@ -49,26 +49,10 @@ class Application(tornado.web.Application):
 		self.backend = Backend()
 
 		# Launch any background jobs
-		self._run_task(queue.dispatch_jobs, 5)
+		self.backend.run_periodic_task(5, queue.dispatch_jobs, self.backend)
 
 		logging.info("Successfully initialied application")
 
 		# Perform some initial tasks
-		self._run_task(self.backend.builders.sync)
-		self._run_task(self.backend.builders.autoscale)
-
-	def _run_task(self, callback, t=None):
-		"""
-			Runs the callback every t seconds in the background or once if t is None
-		"""
-		# Pass backend to the function
-		callback = functools.partial(callback, self.backend)
-
-		# Create a periodic callback object
-		if t:
-			task = tornado.ioloop.PeriodicCallback(callback, t * 1000)
-			task.start()
-
-		else:
-			ioloop = tornado.ioloop.IOLoop.current()
-			ioloop.add_callback(callback)
+		self.backend.run_task(self.backend.builders.sync)
+		self.backend.run_task(self.backend.builders.autoscale)