address issue #9 and other changes to the demo code

examples/echoapp_client.py

@@ -1,6 +1,7 @@
 import websocket
 import thread
 import time
+import sys
 
 def on_message(ws, message):
     print message
@@ -14,20 +15,27 @@ def on_close(ws):
 def on_open(ws):
     def run(*args):
         for i in range(3):
-            time.sleep(1)
+            # send the message, then wait 
+            # so thread doesnt exit and socket
+            # isnt closed
             ws.send("Hello %d" % i)
+            time.sleep(1)
+        
         time.sleep(1)
         ws.close()
-        print "thread terminating..."
+        print "Thread terminating..."
+    
     thread.start_new_thread(run, ())
 
-
 if __name__ == "__main__":
     websocket.enableTrace(True)
-    ws = websocket.WebSocketApp("ws://echo.websocket.org/",
+    if len(sys.argv) < 2:
+        host = "ws://echo.websocket.org/"
+    else:
+        host = sys.argv[1]
+    ws = websocket.WebSocketApp(host,
                                 on_message = on_message,
                                 on_error = on_error,
                                 on_close = on_close)
     ws.on_open = on_open
-    
     ws.run_forever()

websocket.py

@@ -55,7 +55,6 @@ STATUS_INVALID_EXTENSION = 1010
 STATUS_UNEXPECTED_CONDITION = 1011
 STATUS_TLS_HANDSHAKE_ERROR = 1015
 
-
 logger = logging.getLogger()
 
 class WebSocketException(Exception):
@@ -515,7 +514,11 @@ class WebSocket(object):
         """
         while True:
             frame = self.recv_frame()
-            if frame.opcode in (ABNF.OPCODE_TEXT, ABNF.OPCODE_BINARY):
+            if not frame:
+                # handle error: 
+                # 'NoneType' object has no attribute 'opcode'
+                raise WebSocketException("Not a valid frame %s" % frame)
+            elif frame.opcode in (ABNF.OPCODE_TEXT, ABNF.OPCODE_BINARY):
                 return (frame.opcode, frame.data)
             elif frame.opcode == ABNF.OPCODE_CLOSE:
                 self.send_close()