Extract process managing logic to SupervisorMixin from event handlers

lib/tfw/util.py

@@ -1,4 +1,6 @@
 import xmlrpc.client, zmq
+from contextlib import suppress
+from xmlrpc.client import Fault as SupervisorFault
 
 from .config.envvars import SUPERVISOR_HTTP_URI
 
@@ -14,6 +16,17 @@ def create_source_code_response_data(filename, content, language):
 class SupervisorMixin:
     supervisor = xmlrpc.client.ServerProxy(SUPERVISOR_HTTP_URI).supervisor
 
+    def stop_process(self):
+        with suppress(SupervisorFault):
+            self.supervisor.stopProcess(self.process_name)
+
+    def start_process(self):
+        self.supervisor.startProcess(self.process_name)
+
+    def restart_process(self):
+        self.stop_process()
+        self.start_process()
+
 
 class ZMQConnectorBase:
     def __init__(self, zmq_context=None):