for inter-process communication, uses Pipe instead of Queue

github issue #54
merge of commit 629d068 from branch "pipe instead queue" (now
extinct) with some name changes…

DNSServer.py

@@ -124,7 +124,7 @@ def printDNSPaket(paket):
 
 
 
-def Run(cmdQueue, param):
+def Run(cmdPipe, param):
     dinit(__name__, param)  # init logging, DNSServer process
 
     try:
@@ -154,14 +154,11 @@ def Run(cmdQueue, param):
     try:
         while True:
             # check command
-            try:
-                cmd = cmdQueue.get_nowait()
+            if cmdPipe.poll():
+                cmd = cmdPipe.recv()
                 if cmd=='shutdown':
                     break
 
-            except Queue.Empty:
-                pass
-
             # do your work (with timeout)
             try:
                 data, addr = DNS.recvfrom(1024)

PlexConnect.py

@@ -11,7 +11,7 @@
 import sys, time
 from os import sep
 import socket
-from multiprocessing import Process, Queue
+from multiprocessing import Process, Pipe
 
 import PlexGDM
 import DNSServer, WebServer
@@ -46,8 +46,8 @@ def getIP_self():
     dinit('PlexConnect', param)  # re-init logfile with loglevel
 
     if cfg.getSetting('enable_dnsserver')=='True':
-        cmd_DNSServer = Queue()
-    cmd_WebServer = Queue()
+        pipe_DNSServer = Pipe()  # endpoint [0]-PlexConnect, [1]-DNSServer
+    pipe_WebServer = Pipe()  # endpoint [0]-PlexConnect, [1]-WebServer
 
     param['IP_self'] = getIP_self()
     param['IP_DNSMaster'] = cfg.getSetting('ip_dnsmaster')
@@ -70,22 +70,22 @@ def getIP_self():
     dprint('PlexConnect', 0, "PMS: {0}", param['Addr_PMS'])
 
     if cfg.getSetting('enable_dnsserver')=='True':
-        p_DNSServer = Process(target=DNSServer.Run, args=(cmd_DNSServer, param))
+        p_DNSServer = Process(target=DNSServer.Run, args=(pipe_DNSServer[1], param))
         p_DNSServer.start()
 
         time.sleep(0.1)
         if not p_DNSServer.is_alive():
             dprint('PlexConnect', 0, "DNSServer not alive. Shutting down.")
             sys.exit(1)
 
-    p_WebServer = Process(target=WebServer.Run, args=(cmd_WebServer, param))
+    p_WebServer = Process(target=WebServer.Run, args=(pipe_WebServer[1], param))
     p_WebServer.start()
 
     time.sleep(0.1)
     if not p_WebServer.is_alive():
         dprint('PlexConnect', 0, "WebServer not alive. Shutting down.")
         if cfg.getSetting('enable_dnsserver')=='True':
-            cmd_DNSServer.put('shutdown')
+            pipe_DNSServer[0].send('shutdown')
             p_DNSServer.join()
         sys.exit(1)
 
@@ -97,8 +97,8 @@ def getIP_self():
     finally:
         dprint('PlexConnect', 0,  "Shutting down.")
         if cfg.getSetting('enable_dnsserver')=='True':
-            cmd_DNSServer.put('shutdown')
+            pipe_DNSServer[0].send('shutdown')
             p_DNSServer.join()
 
-        cmd_WebServer.put('shutdown')
+        pipe_WebServer[0].send('shutdown')
         p_WebServer.join()

WebServer.py

@@ -167,7 +167,7 @@ def do_GET(self):
 
 
 
-def Run(cmdQueue, param):
+def Run(cmdPipe, param):
     dinit(__name__, param)  # init logging, WebServer process
 
     #Protocol     = "HTTP/1.0"
@@ -192,15 +192,11 @@ def Run(cmdQueue, param):
     try:
         while True:
             # check command
-            try:
-                # check command
-                cmd = cmdQueue.get_nowait()
+            if cmdPipe.poll():
+                cmd = cmdPipe.recv()
                 if cmd=='shutdown':
                     break
 
-            except Queue.Empty:
-                pass
-
             # do your work (with timeout)
             server.handle_request()