get-poetry-simple.py

# This is the Twisted Get Poetry Now! client, version 2.1.

# NOTE: This should not be used as the basis for production code.

import optparse

from twisted.internet.protocol import Protocol, ClientFactory


def parse_args():
    usage = """usage: %prog [options] [hostname]:port ...

This is the Get Poetry Now! client, Twisted version 2.1.
Run it like this:

  python get-poetry-simple.py port1 port2 port3 ...

If you are in the base directory of the twisted-intro package,
you could run it like this:

  python twisted-client-2/get-poetry-simple.py 10001 10002 10003

to grab poetry from servers on ports 10001, 10002, and 10003.

Of course, there need to be servers listening on those ports
for that to work.
"""

    parser = optparse.OptionParser(usage)

    _, 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)


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 # tell base class what proto to build

    def __init__(self, poetry_count):
        self.poetry_count = poetry_count
        self.poems = []

    def poem_finished(self, poem=None):
        if poem is not None:
            self.poems.append(poem)

        self.poetry_count -= 1

        if self.poetry_count == 0:
            self.report()
            from twisted.internet import reactor
            reactor.stop()

    def report(self):
        for poem in self.poems:
            print poem

    def clientConnectionFailed(self, connector, reason):
        print 'Failed to connect to:', connector.getDestination()
        self.poem_finished()


def poetry_main():
    addresses = parse_args()

    factory = PoetryClientFactory(len(addresses))

    from twisted.internet import reactor

    for address in addresses:
        host, port = address
        reactor.connectTCP(host, port, factory)

    reactor.run()


if __name__ == '__main__':
    poetry_main()