move reload functionality to its own file

awx/main/utils/reload.py

@@ -0,0 +1,68 @@
+# Copyright (c) 2017 Ansible Tower by Red Hat
+# All Rights Reserved.
+
+# Python
+import subprocess
+import logging
+
+# Django
+from django.conf import settings
+
+# Celery
+from celery import current_app
+
+logger = logging.getLogger('awx.main.utils.reload')
+
+
+def _uwsgi_reload():
+    # http://uwsgi-docs.readthedocs.io/en/latest/MasterFIFO.html#available-commands
+    logger.warn('Initiating uWSGI chain reload of server')
+    TRIGGER_CHAIN_RELOAD = 'c'
+    with open(settings.UWSGI_FIFO_LOCATION, 'w') as awxfifo:
+        awxfifo.write(TRIGGER_CHAIN_RELOAD)
+
+
+def _reset_celery_thread_pool():
+    # Send signal to restart thread pool
+    app = current_app._get_current_object()
+    app.control.broadcast('pool_restart', arguments={'reload': True},
+                          destination=['celery@{}'.format(settings.CLUSTER_HOST_ID)], reply=False)
+
+
+def _supervisor_service_restart(service_internal_names):
+    '''
+    Service internal name options:
+     - beat - celery - callback - channels - uwsgi - daphne
+     - fact - nginx
+    example use pattern of supervisorctl:
+    # supervisorctl restart tower-processes:receiver tower-processes:factcacher
+    '''
+    group_name = 'tower-processes'
+    args = ['supervisorctl']
+    if settings.DEBUG:
+        args.extend(['-c', '/supervisor.conf'])
+    programs = []
+    name_translation_dict = settings.SERVICE_NAME_DICT
+    for n in service_internal_names:
+        if n in name_translation_dict:
+            programs.append('{}:{}'.format(group_name, name_translation_dict[n]))
+    args.extend(['restart'])
+    args.extend(programs)
+    logger.debug('Issuing command to restart services, args={}'.format(args))
+    subprocess.Popen(args)
+
+
+def restart_local_services(service_internal_names):
+    logger.warn('Restarting services {} on this node in response to user action'.format(service_internal_names))
+    if 'uwsgi' in service_internal_names:
+        _uwsgi_reload()
+        service_internal_names.remove('uwsgi')
+    restart_celery = False
+    if 'celery' in service_internal_names:
+        restart_celery = True
+        service_internal_names.remove('celery')
+    _supervisor_service_restart(service_internal_names)
+    if restart_celery:
+        # Celery restarted last because this probably includes current process
+        _reset_celery_thread_pool()
+