from twisted.internet import protocol, reactor, endpoints class Echo(protocol.Protocol):
def dataReceived(self, data):
self.transport.write(data)
class EchoFactory(protocol.Factory):
def buildProtocol(self, addr):
return Echo()
endpoints.serverFromString(reactor, "tcp:1234").listen(EchoFactory()) reactor.run()
from twisted.web import server, resource from twisted.internet import reactor, endpoints class Counter(resource.Resource): isLeaf = True numberRequests = 0 def render_GET(self, request): self.numberRequests += 1 request.setHeader(b"content-type", b"text/plain") content = u"I am request #{}\n".format(self.numberRequests)
return content.encode("ascii") endpoints.serverFromString(reactor, "tcp:8080").listen(server.Site(Counter()))
reactor.run()
from twisted.internet import reactor, protocol, endpoints
from twisted.protocols import basic
class PubProtocol(basic.LineReceiver):
def __init__(self, factory):
self.factory = factory
def connectionMade(self):
self.factory.clients.add(self)
def connectionLost(self, reason):
self.factory.clients.remove(self)
def lineReceived(self, line):
for c in self.factory.clients:
source = u"<{}> ".format(self.transport.getHost()).encode("ascii")
c.sendLine(source + line)
class PubFactory(protocol.Factory):
def __init__(self):
self.clients = set()
def buildProtocol(self, addr):
return PubProtocol(self)
endpoints.serverFromString(reactor, "tcp:1025").listen(PubFactory())
reactor.run()
你可以使用打开两个命令行终端,使用 telnet localhost 1025, 然后在每个终端输入。
from __future__ import print_function
import sys
from twisted.internet import protocol, defer, endpoints, task
from twisted.mail import imap4
from twisted.python import failure
@defer.inlineCallbacks
def main(reactor, username="alice", password="secret",
strport="tls:example.com:993"):
endpoint = endpoints.clientFromString(reactor, strport)
factory = protocol.Factory.forProtocol(imap4.IMAP4Client)
try:
client = yield endpoint.connect(factory)
yield client.login(username, password)
yield client.select(‘INBOX‘)
info = yield client.fetchEnvelope(imap4.MessageSet(1))
print(‘First message subject:‘, info[1][‘ENVELOPE‘][1])
except:
print("IMAP4 client interaction failed")
failure.Failure().printTraceback()
task.react(main, sys.argv[1:])
总结
twisted 是一个封装了各个网络协议,基于事件循环驱动的框架。
1. 要使用twisted框架,需实现一个twisted Protocol类的客户端或服务器类,重写其dataReceived,
定义接受到对端数据时的处理方法。
2. 对于服务器类(客户端类),还要实现一个twisted Factory(ClientFactory)类,用来管理Protocol类,当有新的客户端连接时,框架调用
Factory.buildProtocol()返回Protocol类去处理相应连接。
3. 使用twisted 相应的listen/connect方法,监听/连接对端服务。
4. 最后,调用twisted的事件循环处理类reactor.run(),启动事件循环。
class BaseProtocol:
"""
This is the abstract superclass of all protocols.
Some methods have helpful default implementations here so that they can
easily be shared, but otherwise the direct subclasses of this class are more
interesting, L{Protocol} and L{ProcessProtocol}.
"""
connected = 0
transport = None
def makeConnection(self, transport):
"""Make a connection to a transport and a server.
This sets the ‘transport‘ attribute of this Protocol, and calls the
connectionMade() callback.
"""
self.connected = 1
self.transport = transport
self.connectionMade()
def connectionMade(self):
"""Called when a connection is made.
This may be considered the initializer of the protocol, because
it is called when the connection is completed. For clients,
this is called once the connection to the server has been
established; for servers, this is called after an accept() call
stops blocking and a socket has been received. If you need to
send any greeting or initial message, do it here.
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}
原文:http://www.cnblogs.com/linyihai/p/7395875.html