Binary conversion and zlib compression

src/client/connection.py

@@ -1,12 +1,12 @@
 
-# import zlib
+import zlib
 import threading
 import json
 import copy
 from twisted.internet import reactor
 from autobahn.twisted.websocket import WebSocketClientProtocol
 from autobahn.twisted.websocket import WebSocketClientFactory
-
+from struct import *
 
 class MMClient(WebSocketClientProtocol):
 
@@ -20,6 +20,13 @@ def onMessage(self, payload, is_binary):
         if not is_binary:
             data = json.loads(payload)
             MMClient.updates[data["topic"]] = data
+        else:
+            decompressed = zlib.decompress(payload)
+            size = unpack('=I', decompressed[:4])
+            frmt = "%ds" % size[0]
+            unpacked = unpack('=I' + frmt, decompressed)
+            data = json.loads(unpacked[1])
+            MMClient.updates[data["topic"]] = data
 
     @staticmethod
     def send_message(payload, is_binary):
@@ -47,8 +54,13 @@ def stop(self):
 
     def send_message(self, data):
         payload = json.dumps(data)
-        is_binary = False
-        return MMClient.send_message(payload, is_binary)
+        frmt = "%ds" % len(payload)
+        binary = pack(frmt, payload)
+        binLen = len(binary)
+        binary = pack('=I' + frmt, binLen, payload)
+        compressed = zlib.compress(binary)
+	is_binary = True
+        return MMClient.send_message(compressed, is_binary)
 
     def updates(self):
         payloads = copy.copy(MMClient.updates)

src/server/server_node.py

@@ -12,7 +12,7 @@
 
 
 def run_server(host, port):
-    log.startLogging(sys.stdout)
+    #log.startLogging(sys.stdout)
     url = "ws://{}:{}".format(host, port)
     factory = WebSocketServerFactory(url, debug=True)
     factory.protocol = ws.MMServerProtocol

src/server/ws.py

@@ -1,12 +1,12 @@
 
-# import zlib
+import zlib
 import json
 import rospy
 import time
 import common
 from std_msgs.msg import Float32
 from autobahn.twisted.websocket import WebSocketServerProtocol
-
+from struct import *
 
 class MMServerProtocol(WebSocketServerProtocol):
 
@@ -31,6 +31,27 @@ def onMessage(self, payload, is_binary):
                     common.get_client(msg["to"]).sendMessage(payload)
             except KeyError:
                 pass
+        else:
+            try:
+                receivedTime = time.time()
+                decompressed = zlib.decompress(payload)
+                size = unpack('=I', decompressed[:4])
+                frmt = "%ds" % size[0]
+                unpacked = unpack('=I' + frmt, decompressed)
+                msg = json.loads(unpacked[1])
+                latency = Float32()
+                latency.data = receivedTime - msg["stamp"]
+                self.lat_pub.publish(latency)
+                if msg["to"] == "*":
+                    for name in common.clients.keys():
+                        if name != msg["from"]:
+                            common.get_client(name).sendMessage(payload, True)
+                else:
+                    common.get_client(msg["to"]).sendMessage(payload, True)
+            except KeyError:
+                pass
+
+
 
     def onClose(self, was_clean, code, reason):
         common.remove_client(self.name_of_client)