From fa1f7da1c39765cbc08324ce5e99779d47f0ec39 Mon Sep 17 00:00:00 2001
From: Calum Halcrow <calumhalcrow@gmail.com>
Date: Mon, 19 Dec 2011 18:27:41 +0800
Subject: [PATCH] Method to build RabbitMQ connection_parameters.

---
 chat/chatroom.py           | 46 +++++++++++++++++++++-----------------
 frontend/events/signals.py |  5 ++++-
 server.py                  |  9 +++-----
 3 files changed, 33 insertions(+), 27 deletions(-)

diff --git a/chat/chatroom.py b/chat/chatroom.py
index 9bfd473..cff9b6f 100644
--- a/chat/chatroom.py
+++ b/chat/chatroom.py
@@ -1,5 +1,6 @@
 #! /usr/bin/env python
-from os import path as op
+import os
+import os.path as op
 import signal
 import pika
 from pika.adapters.tornado_connection import TornadoConnection
@@ -11,6 +12,7 @@
 from lib.observer import Observable
 import django.core.handlers.wsgi
 from urlparse import urlparse
+from django.conf import settings
 
 ROOT = op.normpath(op.join(op.dirname(__file__), '../'))
 
@@ -33,13 +35,11 @@ def send_message(self, message):
 
 
 class PikaClient(Observable):
-    def __init__(self, queue_name, rabbitmq_url):
+    def __init__(self):
         Observable.__init__(self)
 
-        self.queue_name = queue_name
-
-        # amqp://uname:pwd@host.heroku.srs.rabbitmq.com:13029/vhost
-        self.rabbitmq_url = urlparse(rabbitmq_url)
+        #self.queue_name = settings.RABBITMQ_QUEUE_NAME
+        self.queue_name = 'hello'
 
         # States
         self.connected = False
@@ -52,6 +52,22 @@ def __init__(self, queue_name, rabbitmq_url):
         # Message caches
         self.messages = list()
 
+    # amqp://uname:pwd@host.heroku.srs.rabbitmq.com:13029/vhost
+    def connection_parameters(self):
+        rabbitmq_url = urlparse('RABBITMQ_URL' in os.environ and os.environ['RABBITMQ_URL'] or 'amqp://localhost')
+
+        connection_parameters = {'host': rabbitmq_url.hostname}
+        if rabbitmq_url.port:
+            connection_parameters['port'] = rabbitmq_url.port
+        if rabbitmq_url.username:
+            connection_parameters['credentials'] = pika.PlainCredentials(
+                rabbitmq_url.username,
+                rabbitmq_url.password)
+        if rabbitmq_url.path:
+            connection_parameters['virtual_host'] = rabbitmq_url.path
+
+        return connection_parameters
+
     def connect(self):
         if self.connecting:
             pika.log.info('Already connecting to RabbitMQ')
@@ -59,18 +75,8 @@ def connect(self):
         pika.log.info('Connecting to RabbitMQ')
         self.connecting = True
 
-        # build RabbitMQ connection parameters:
-        connection_params = {'host': self.rabbitmq_url.hostname}
-        if self.rabbitmq_url.port:
-            connection_params['port'] = self.rabbitmq_url.port
-        if self.rabbitmq_url.username:
-            connection_params['credentials'] = pika.PlainCredentials(
-                self.rabbitmq_url.username,
-                self.rabbitmq_url.password)
-        if self.rabbitmq_url.path:
-            connection_params['virtual_host'] = self.rabbitmq_url.path
-
-        param = pika.ConnectionParameters(**connection_params)
+        connection_parameters = self.connection_parameters()
+        param = pika.ConnectionParameters(**connection_parameters)
 
         self.connection = TornadoConnection(param,
                 on_open_callback=self.on_connected)
@@ -110,7 +116,7 @@ def get_messages(self):
 
 
 class Application():
-    def __init__(self, port, rabbitmq_url):
+    def __init__(self, port):
         settings = {
             'debug': True,
             'enabled_protocols': ['websocket',
@@ -130,7 +136,7 @@ def __init__(self, port, rabbitmq_url):
                 (r'.*', tornado.web.FallbackHandler, {'fallback': wsgi_app}),
             ], **settings)
 
-        self.message_queue = PikaClient('hello', rabbitmq_url)
+        self.message_queue = PikaClient()
         self.message_queue.attach(self)
         self.server = None
 
diff --git a/frontend/events/signals.py b/frontend/events/signals.py
index ddb0ead..b091f47 100644
--- a/frontend/events/signals.py
+++ b/frontend/events/signals.py
@@ -5,8 +5,11 @@
 from events.models import Message, Checkin
 from django.utils import simplejson
 
+from chat.chatroom import PikaClient
+
 def publish(data):
-    connection = pika.BlockingConnection(pika.ConnectionParameters(**settings.RABBITMQ_CONN))
+    connection_parameters = PikaClient().connection_parameters()
+    connection = pika.BlockingConnection(pika.ConnectionParameters(**connection_parameters))
     channel = connection.channel()
     channel.queue_declare(queue=settings.RABBITMQ_QUEUE_NAME)
 
diff --git a/server.py b/server.py
index 4b08e4d..b714213 100755
--- a/server.py
+++ b/server.py
@@ -11,13 +11,13 @@
 from chat.chatroom import Application
 
 ROOT = op.normpath(op.dirname(__file__))
-def main(port, rabbitmq_url):
+def main(port):
     # Starting Django
     sys.path.append(op.join(ROOT, 'frontend'))
     os.environ['DJANGO_SETTINGS_MODULE'] = 'frontend.settings'
 
     # Tornadio app part
-    app = Application(port, rabbitmq_url)
+    app = Application(port)
     # Cleanup code
     def shutdown(sig, frame):
         app.stop()
@@ -36,7 +36,4 @@ def shutdown(sig, frame):
     parser.add_option('-p', '--port', dest='port', help='Specify the socket IO port')
     (options, args) = parser.parse_args()
 
-    rabbitmq_url = 'RABBITMQ_URL' in os.environ and os.environ['RABBITMQ_URL'] or 'amqp://localhost'
-
-    main(port=options.port or 8001,
-         rabbitmq_url=rabbitmq_url)
+    main(port=options.port or 8001)