some source code about twisted

1_7.http_proxy_server/python/twisted-intro-dave/solutions/README

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+This directory contains my own solutions to some of the exercises.
+I will post more as I have time.

1_7.http_proxy_server/python/twisted-intro-dave/solutions/part-8/number-1/get-poetry.py

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+import optparse, sys
+
+from twisted.internet import defer
+from twisted.internet.protocol import Protocol, ClientFactory
+
+
+class TimeoutError(Exception):
+    pass
+
+
+def parse_args():
+    usage = """usage: %prog [options] [hostname]:port ...
+
+Get Poetry Now!
+
+Run it like this:
+
+  python get-poetry.py port1 port2 port3 ...
+"""
+
+    parser = optparse.OptionParser(usage)
+
+    help = "Timeout in seconds."
+    parser.add_option('-t', '--timeout', type='float', help=help, default=5.0)
+
+    options, addresses = parser.parse_args()
+
+    if not addresses:
+        print parser.format_help()
+        parser.exit()
+
+    def parse_address(addr):
+        if ':' not in addr:
+            host = '127.0.0.1'
+            port = addr
+        else:
+            host, port = addr.split(':', 1)
+
+        if not port.isdigit():
+            parser.error('Ports must be integers.')
+
+        return host, int(port)
+
+    return map(parse_address, addresses), options
+
+
+class PoetryProtocol(Protocol):
+
+    poem = ''
+
+    def dataReceived(self, data):
+        self.poem += data
+
+    def connectionLost(self, reason):
+        self.poemReceived(self.poem)
+
+    def poemReceived(self, poem):
+        self.factory.poem_finished(poem)
+
+
+class PoetryClientFactory(ClientFactory):
+
+    protocol = PoetryProtocol
+
+    def __init__(self, deferred, timeout):
+        self.deferred = deferred
+        self.timeout = timeout
+        self.timeout_call = None
+
+    def startedConnecting(self, connector):
+        from twisted.internet import reactor
+        self.timeout_call = reactor.callLater(self.timeout,
+                                              self.on_timeout,
+                                              connector)
+
+    def poem_finished(self, poem):
+        if self.deferred is not None:
+            d, self.deferred = self.deferred, None
+            d.callback(poem)
+        self.cancel_timeout()
+
+    def clientConnectionFailed(self, connector, reason):
+        if self.deferred is not None:
+            d, self.deferred = self.deferred, None
+            d.errback(reason)
+        self.cancel_timeout()
+
+    def on_timeout(self, connector):
+        self.timeout_call = None
+
+        if self.deferred is not None:
+            d, self.deferred = self.deferred, None
+            d.errback(TimeoutError())
+            connector.disconnect()
+
+    def cancel_timeout(self):
+        if self.timeout_call is not None:
+            call, self.timeout_call = self.timeout_call, None
+            call.cancel()
+
+
+def get_poetry(host, port, timeout):
+    """
+    Download a poem from the given host and port. This function
+    returns a Deferred which will be fired with the complete text of
+    the poem or a Failure if the poem could not be downloaded.
+
+    If timeout seconds elapse before the poem is received, the
+    Deferred will fire with a TimeoutError.
+    """
+    d = defer.Deferred()
+    from twisted.internet import reactor
+    factory = PoetryClientFactory(d, timeout)
+    reactor.connectTCP(host, port, factory)
+    return d
+
+
+def poetry_main():
+    addresses, options = parse_args()
+
+    from twisted.internet import reactor
+
+    poems = []
+    errors = []
+
+    def got_poem(poem):
+        poems.append(poem)
+
+    def poem_failed(err):
+        print >>sys.stderr, 'Poem failed:', err
+        errors.append(err)
+
+    def poem_done(_):
+        if len(poems) + len(errors) == len(addresses):
+            reactor.stop()
+
+    for address in addresses:
+        host, port = address
+        d = get_poetry(host, port, options.timeout)
+        d.addCallbacks(got_poem, poem_failed)
+        d.addBoth(poem_done)
+
+    reactor.run()
+
+    for poem in poems:
+        print poem
+
+
+if __name__ == '__main__':
+    poetry_main()