From c1b6000817fcba372c83667e1175b563bc83ffc0 Mon Sep 17 00:00:00 2001
From: Denis Bilenko <denis@ag-projects.com>
Date: Fri, 24 Oct 2008 19:33:10 +0700
Subject: [PATCH] added an example on using twisted and blocking urllib2-based
 library

---
 examples/twisted_ex4_xcap_proxy.py | 94 ++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 examples/twisted_ex4_xcap_proxy.py

diff --git a/examples/twisted_ex4_xcap_proxy.py b/examples/twisted_ex4_xcap_proxy.py
new file mode 100644
index 0000000..22a00da
--- /dev/null
+++ b/examples/twisted_ex4_xcap_proxy.py
@@ -0,0 +1,94 @@
+from twisted.internet import pollreactor; pollreactor.install()
+from twisted.internet.protocol import Factory
+from twisted.internet import reactor
+from twisted.protocols import basic
+from twisted.internet.error import ConnectionDone
+
+from xcaplib.client import XCAPClient
+
+from eventlet.api import spawn, get_hub
+from eventlet.channel import channel
+
+class LineOnlyReceiver(basic.LineOnlyReceiver):
+
+    def __init__(self, channel):
+        self.channel = channel
+
+    def lineReceived(self, line):
+        spawn(self.channel.send, line)
+
+    def connectionLost(self, reason):
+        self.channel.send_exception(reason.value)
+
+
+class line_only_receiver:
+
+    def __init__(self, protocol, channel):
+        self.protocol = protocol
+        self.channel = channel
+
+    def readline(self):
+        return self.channel.receive()
+
+    def send(self, data):
+        self.protocol.transport.write(data)
+
+    def sendline(self, line):
+        self.protocol.sendLine(line)
+
+    # iterator protocol:
+
+    def __iter__(self):
+        return self
+
+    def next(self):
+        try:
+            return self.readline()
+        except ConnectionDone:
+            raise StopIteration
+
+
+class MyFactory(Factory):
+    protocol = LineOnlyReceiver
+
+    def __init__(self, handler):
+        self.handler = handler
+
+    def buildProtocol(self, addr):
+        ch = channel()
+        p = self.protocol(ch)
+        p.factory = self
+        spawn(self.handler, line_only_receiver(p, ch))
+        return p
+
+def xcaplib_enable_eventlet():
+    from eventlet.green import urllib2, socket as greensocket, time as greentime
+    from xcaplib import httpclient
+    # replacing all the references to the old urllib2 in xcaplib:
+    httpclient.urllib2 = urllib2
+    httpclient.HTTPRequest.__bases__ = (urllib2.Request,)
+
+xcaplib_enable_eventlet()
+client = XCAPClient('https://xcap.sipthor.net/xcap-root', 'alice@example.com', '123')
+
+def perform_request(line):
+    app, context, node = (line + ' ').split(' ', 3) 
+    context = {'u' : 'users', 'g': 'global'}.get(context, context)
+    try:
+        return str(client._get(app, node, globaltree=context=='global'))
+    except Exception, ex:
+        return str(ex)
+
+def handler(conn):
+    peer = conn.protocol.transport.getPeer()
+    print 'new connection from %s' % (peer, )
+    try:
+        for line in conn:
+            print 'received from %s: %s' % (peer, line)
+            print perform_request(line)
+        print peer, 'connection done'
+    except Exception, ex:
+        print peer, ex
+
+reactor.listenTCP(8007, MyFactory(handler))
+get_hub().switch()