用Python实现一个简易的WebSoc

</pre><pre name="code" class="python">#coding=utf-8

from threading import Thread
import struct
import time
import hashlib
import base64
import socket
import time  

class returnCrossDomain(Thread):  
    def __init__(self,connection):  
        Thread.__init__(self)  
        self.con = connection  
        self.isHandleShake = False  
    def run(self):  
        while True:  
            if not self.isHandleShake: 
                #开始握手阶段
                header = self.analyzeReq()
                secKey = header['Sec-WebSocket-Key'];  

                acceptKey = self.generateAcceptKey(secKey)

                response = "HTTP/1.1 101 Switching Protocols\r\n"  
                response += "Upgrade: websocket\r\n"  
                response += "Connection: Upgrade\r\n" 
                response += "Sec-WebSocket-Accept: %s\r\n\r\n"%(acceptKey.decode('utf-8'))  
                self.con.send(response.encode())  
                self.isHandleShake = True  
                print('response:\r\n'+response)
                #握手阶段结束
            else:  
                #接受客户端数据
                opcode = self.getOpcode()  
                if opcode == 8:
                    self.con.close()
                self.getDataLength()
                clientData = self.readClientData()
                print('客户端数据：'+clientData)
                #向客户端发送数据
                self.sendDataToClient('hello world')


    def analyzeReq(self):
        reqData = self.con.recv(1024).decode()
        reqList = reqData.split('\r\n')
        headers = {}
        for reqItem in reqList:
            if ': ' in reqItem:
                unit = reqItem.split(': ')
                headers[unit[0]] = unit[1]
        return headers

    def generateAcceptKey(self,secKey):
        sha1 = hashlib.sha1()
        sha1.update((secKey+'258EAFA5-E914-47DA-95CA-C5AB0DC85B11').encode())
        sha1_result = sha1.digest()
        acceptKey = base64.b64encode(sha1_result)
        return acceptKey

    def getOpcode(self):
        first8Bit = self.con.recv(1)
        first8Bit = struct.unpack('B',first8Bit)[0]
        opcode = first8Bit & 0b00001111
        return opcode

    def getDataLength(self):
        second8Bit = self.con.recv(1)
        second8Bit = struct.unpack('B',second8Bit)[0]
        masking = second8Bit >> 7
        dataLength = second8Bit & 0b01111111

        if dataLength <= 125:
            payDataLength = dataLength
        elif dataLength == 126:
            payDataLength = struct.unpack('H',self.con.recv(2))[0]
        elif dataLength == 127:
            payDataLength = struct.unpack('Q',self.con.recv(8))[0]
        self.masking = masking
        self.payDataLength = payDataLength

    def readClientData(self):
        if self.masking == 1:
            maskingKey = self.con.recv(4)

        data = self.con.recv(self.payDataLength)

        if self.masking == 1:
            i = 0
            trueData = ''
            for d in data:
                trueData += chr(d ^ maskingKey[i%4])
                i += 1
            return trueData
        else:
            return data

    def sendDataToClient(self,text):
        sendData = ''
        sendData = struct.pack('!B',0x81)
   
        length = len(text)
        if length <= 125:
            sendData += struct.pack('!B',length)
        elif length <= 65536:
            sendData += struct.pack('!B',126)
            sendData += struct.pack('!H',length)
        elif length == 127:
            sendData += struct.pack('!B',127)
            sendData += struct.pack('!Q',length)

        sendData += struct.pack('!%ds' % (length),text.encode())
        dataSize = self.con.send(sendData)

  
def main():  
    sock = socket.socket(socket.AF_INET,socket.SOCK_STREAM)  
    sock.bind(('127.0.0.1',88))  
    sock.listen(5)  
    while True:  
        try:  
            connection,address = sock.accept()  
            returnCrossDomain(connection).start()  
        except:  
            time.sleep(1)  
  
if __name__=="__main__":  
    main()