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):

src/event_handlers/source_code_event_handler.py

@@ -1,7 +1,5 @@
 from shutil import copy, rmtree, copytree
 from os.path import splitext
-from contextlib import suppress
-from xmlrpc.client import Fault as SupervisorFault
 
 from tfw.util import SupervisorMixin
 from tfw.config import LOGIN_APP_DIR
@@ -43,19 +41,16 @@ class SourceCodeEventHandler(EventHandlerBase, SupervisorMixin):
         data = data_json['data']
         with open(self.file, 'w') as ofile:
             ofile.write(data['content'])
-        self.supervisor.stopProcess(self.process_name)
-        self.supervisor.startProcess(self.process_name)
+        self.restart_process()
 
     def create_initial_state(self):
-        with suppress(SupervisorFault):
-            self.supervisor.stopProcess(self.process_name)
+        self.stop_process()
 
         rmtree(self.working_directory, ignore_errors=True)
         copytree('source_code_server/', self.working_directory)
         file = copy(self.filename, self.working_directory)
 
-        self.supervisor.startProcess(self.process_name)
-
+        self.start_process()
         return file
 
 

src/event_handlers/terminado_event_handler.py

@@ -17,7 +17,7 @@ class TerminadoEventHandler(EventHandlerBase, SupervisorMixin):
     def setup_terminado_server(self):
         rmtree(self.working_directory, ignore_errors=True)
         copytree('terminado_server/', self.working_directory)
-        self.supervisor.startProcess(self.process_name)
+        self.start_process()
 
     def handle_event(self, anchor, data_json):
         log.debug('TerminadoEventHandler received event for anchor {}'.format(anchor))