Python 网络框架Twisted基础学习及详细讲解

# coding=utf-8
from twisted.internet.protocol import Protocol
from twisted.internet.protocol import Factory
from twisted.internet.endpoints import TCP4ServerEndpoint
from twisted.internet import reactor


clients = []


class Spreader(Protocol):
    def __init__(self, factory):
        self.factory = factory

    def connectionMade(self):
        self.factory.numProtocols = self.factory.numProtocols + 1
        self.transport.write(
            "欢迎来到Spread Site, 你是第%s个客户端用户!\n" % (self.factory.numProtocols)
        )
        print "new connect: %d" % (self.factory.numProtocols)
        clients.append(self)

    def connectionLost(self, reason):
        self.factory.numProtocols = self.factory.numProtocols - 1
        clients.remove(self)
        print "lost connect: %d" % (self.factory.numProtocols)

    def dataReceived(self, data):
        if data == "close":
            self.transport.loseConnection()
            for client in clients:
                if client != self:
                    client.transport.write(data)
        else:
            print data


class SpreadFactory(Factory):
    def __init__(self):
        self.numProtocols = 0

    def buildProtocol(self, addr):
        return Spreader(self)


endpoint = TCP4ServerEndpoint(reactor, 8007)
endpoint.listen(SpreadFactory())
reactor.run()

@implementer(interfaces.IProtocolFactory, interfaces.ILoggingContext)
@_oldStyle
class Factory:
    """
    This is a factory which produces protocols.

    By default, buildProtocol will create a protocol of the class given in
    self.protocol.
    """

    # put a subclass of Protocol here:
    protocol = None

    numPorts = 0
    noisy = True

    @classmethod
    def forProtocol(cls, protocol, *args, **kwargs):
        """
        Create a factory for the given protocol.

        It sets the C{protocol} attribute and returns the constructed factory
        instance.

        @param protocol: A L{Protocol} subclass

        @param args: Positional arguments for the factory.

        @param kwargs: Keyword arguments for the factory.

        @return: A L{Factory} instance wired up to C{protocol}.
        """
        factory = cls(*args, **kwargs)
        factory.protocol = protocol
        return factory


    def logPrefix(self):
        """
        Describe this factory for log messages.
        """
        return self.__class__.__name__


    def doStart(self):
        """Make sure startFactory is called.

        Users should not call this function themselves!
        """
        if not self.numPorts:
            if self.noisy:
                _loggerFor(self).info("Starting factory {factory!r}",
                                      factory=self)
            self.startFactory()
        self.numPorts = self.numPorts + 1

    def doStop(self):
        """Make sure stopFactory is called.

        Users should not call this function themselves!
        """
        if self.numPorts == 0:
            # this shouldn't happen, but does sometimes and this is better
            # than blowing up in assert as we did previously.
            return
        self.numPorts = self.numPorts - 1
        if not self.numPorts:
            if self.noisy:
                _loggerFor(self).info("Stopping factory {factory!r}",
                                      factory=self)
            self.stopFactory()

    def startFactory(self):
        """This will be called before I begin listening on a Port or Connector.

        It will only be called once, even if the factory is connected
        to multiple ports.

        This can be used to perform 'unserialization' tasks that
        are best put off until things are actually running, such
        as connecting to a database, opening files, etcetera.
        """

    def stopFactory(self):
        """This will be called before I stop listening on all Ports/Connectors.

        This can be overridden to perform 'shutdown' tasks such as disconnecting
        database connections, closing files, etc.

        It will be called, for example, before an application shuts down,
        if it was connected to a port. User code should not call this function
        directly.
        """


    def buildProtocol(self, addr):
        """
        Create an instance of a subclass of Protocol.

        The returned instance will handle input on an incoming server
        connection, and an attribute "factory" pointing to the creating
        factory.

        Alternatively, L{None} may be returned to immediately close the
        new connection.

        Override this method to alter how Protocol instances get created.

        @param addr: an object implementing L{twisted.internet.interfaces.IAddress}
        """
        p = self.protocol()
        p.factory = self
        return p

@implementer(interfaces.IProtocol, interfaces.ILoggingContext)
class Protocol(BaseProtocol):
    """
    This is the base class for streaming connection-oriented protocols.

    If you are going to write a new connection-oriented protocol for Twisted,
    start here.  Any protocol implementation, either client or server, should
    be a subclass of this class.

    The API is quite simple.  Implement L{dataReceived} to handle both
    event-based and synchronous input; output can be sent through the
    'transport' attribute, which is to be an instance that implements
    L{twisted.internet.interfaces.ITransport}.  Override C{connectionLost} to be
    notified when the connection ends.

    Some subclasses exist already to help you write common types of protocols:
    see the L{twisted.protocols.basic} module for a few of them.
    """

    def logPrefix(self):
        """
        Return a prefix matching the class name, to identify log messages
        related to this protocol instance.
        """
        return self.__class__.__name__


    def dataReceived(self, data):
        """Called whenever data is received.

        Use this method to translate to a higher-level message.  Usually, some
        callback will be made upon the receipt of each complete protocol
        message.

        @param data: a string of indeterminate length.  Please keep in mind
            that you will probably need to buffer some data, as partial
            (or multiple) protocol messages may be received!  I recommend
            that unit tests for protocols call through to this method with
            differing chunk sizes, down to one byte at a time.
        """

    def connectionLost(self, reason=connectionDone):
        """Called when the connection is shut down.

        Clear any circular references here, and any external references
        to this Protocol.  The connection has been closed.

        @type reason: L{twisted.Python.failure.Failure}
        """