Moves the server from using run_app api to using TCPSite

src/app.py

@@ -2,6 +2,7 @@
 import logging
 import pathlib
 import re
+import signal
 import time
 
 import aiojobs
@@ -40,8 +41,7 @@ async def database_backup_routine(app):
         pass
 
 
-# noinspection PyDeprecation
-async def start_background_tasks(app: web.Application):
+async def start_background_tasks(app):
     app['reader'] = obtain_connection(app['db_path'], True)
     app['waitful_backup'] = app.loop.create_task(database_backup_routine(app))
     app['comment_scheduler'] = await aiojobs.create_scheduler(limit=1, pending_limit=0)
@@ -49,15 +49,7 @@ async def start_background_tasks(app: web.Application):
     app['writer'] = app['db_writer'].connection
 
 
-def insert_to_config(app, conf=None, db_file=None):
-    db_file = db_file if db_file else 'DEFAULT'
-    app['config'] = conf
-    app['db_path'] = conf['PATH'][db_file]
-    app['backup'] = re.sub(r'\.db$', '.backup.db', app['db_path'])
-    assert app['db_path'] != app['backup']
-
-
-async def cleanup_background_tasks(app):
+async def stop_background_tasks(app):
     logger.info('Ending background backup loop')
     app['waitful_backup'].cancel()
     await app['waitful_backup']
@@ -65,33 +57,66 @@ async def cleanup_background_tasks(app):
     app['writer'].close()
 
 
-def create_app(conf, db_path='DEFAULT', **kwargs):
-    app = web.Application()
-    app['START_TIME'] = int(time.time())
-    insert_to_config(app, conf, db_path)
-    app.on_startup.append(setup_db_schema)
-    app.on_startup.append(start_background_tasks)
-    app.on_shutdown.append(cleanup_background_tasks)
-    app.on_shutdown.append(close_comment_scheduler)
-    aiojobs.aiohttp.setup(app, **kwargs)
-    app.add_routes([
-        web.post('/api', api_endpoint),
-        web.get('/', get_api_endpoint),
-        web.get('/api', get_api_endpoint)
-    ])
-    return app
+class CommentDaemon:
+    def __init__(self, config, db_path=None, **kwargs):
+        self.config = config
+        app = web.Application()
+        self.insert_to_config(app, config, db_file=db_path)
+        app.on_startup.append(setup_db_schema)
+        app.on_startup.append(start_background_tasks)
+        app.on_shutdown.append(stop_background_tasks)
+        app.on_shutdown.append(close_comment_scheduler)
+        aiojobs.aiohttp.setup(app, **kwargs)
+        app.add_routes([
+            web.post('/api', api_endpoint),
+            web.get('/', get_api_endpoint),
+            web.get('/api', get_api_endpoint)
+        ])
+        self.app = app
+        self.app_runner = web.AppRunner(app)
+        self.app_site = None
+
+    async def start(self):
+        self.app['START_TIME'] = time.time()
+        await self.app_runner.setup()
+        self.app_site = web.TCPSite(
+            runner=self.app_runner,
+            host=self.config['HOST'],
+            port=self.config['PORT'],
+        )
+        await self.app_site.start()
+        logger.info(f'Comment Server is running on {self.config["HOST"]}:{self.config["PORT"]}')
+
+    async def stop(self):
+        await self.app.shutdown()
+        await self.app.cleanup()
+        await self.app_runner.cleanup()
+
+    @staticmethod
+    def insert_to_config(app, conf=None, db_file=None):
+        db_file = db_file if db_file else 'DEFAULT'
+        app['config'] = conf
+        app['db_path'] = conf['PATH'][db_file]
+        app['backup'] = re.sub(r'\.db$', '.backup.db', app['db_path'])
+        assert app['db_path'] != app['backup']
 
 
 def run_app(config):
-    appl = create_app(conf=config, db_path='DEFAULT', close_timeout=5.0)
+    comment_app = CommentDaemon(config=config, db_path='DEFAULT', close_timeout=5.0)
+
+    loop =  asyncio.get_event_loop()
+    loop.set_debug(True)
+
+    def __exit():
+        raise web.GracefulExit()
+
+    loop.add_signal_handler(signal.SIGINT, __exit)
+    loop.add_signal_handler(signal.SIGTERM, __exit)
+
     try:
-        asyncio.run(web.run_app(
-            app=appl,
-            access_log=logging.getLogger('aiohttp.access'),
-            host=config['HOST'],
-            port=config['PORT']
-        ))
-    except asyncio.CancelledError:
+        loop.run_until_complete(comment_app.start())
+        loop.run_forever()
+    except (web.GracefulExit, KeyboardInterrupt, asyncio.CancelledError, ValueError):
         logging.warning('Server going down, asyncio loop raised cancelled error:')
-    except ValueError:
-        logging.exception('Server going down due to value error:')
+    finally:
+        loop.run_until_complete(comment_app.stop())