better server-ready event: notify waiting thread if server really ready (communication ready) or failed to start

fail2ban/client/fail2banserver.py

@@ -184,13 +184,19 @@ class Fail2banServer(Fail2banCmdLine):
 				logSys.log(5, '  server phase %s', phase)
 				if not phase.get('start', False):
 					raise ServerExecutionException('Async configuration of server failed')
+				# event for server ready flag:
+				def _server_ready():
+					phase['start-ready'] = True
+					logSys.log(5, '  server phase %s', phase)
+				# notify waiting thread if server really ready
+				self._conf['onstart'] = _server_ready
 
 			# Start server, daemonize it, etc.
 			pid = os.getpid()
 			server = Fail2banServer.startServerDirect(self._conf, background)
+			# notify waiting thread server ready resp. done (background execution, error case, etc):
 			if not async:
-				phase['start-ready'] = True
+				_server_ready()
-				logSys.log(5, '  server phase %s', phase)
 			# If forked - just exit other processes
 			if pid != os.getpid(): # pragma: no cover
 				os._exit(0)

fail2ban/server/asyncserver.py

@@ -147,6 +147,7 @@ class AsyncServer(asyncore.dispatcher):
 		self.__sock = "/var/run/fail2ban/fail2ban.sock"
 		self.__init = False
 		self.__active = False
+		self.onstart = None
 
 	##
 	# Returns False as we only read the socket first.
@@ -196,6 +197,9 @@ class AsyncServer(asyncore.dispatcher):
 		self.listen(1)
 		# Sets the init flag.
 		self.__init = self.__loop = self.__active = True
+		# Execute on start event (server ready):
+		if self.onstart:
+			self.onstart()
 		# Event loop as long as active:
 		loop(lambda: self.__loop, use_poll=use_poll)
 		self.__active = False

fail2ban/server/server.py

@@ -148,6 +148,7 @@ class Server:
 		logSys.debug("Starting communication")
 		try:
 			self.__asyncServer = AsyncServer(self.__transm)
+			self.__asyncServer.onstart = conf.get('onstart')
 			self.__asyncServer.start(sock, force)
 		except AsyncServerException as e:
 			logSys.error("Could not start server: %s", e)