Based concurrency of socket programming socketsever

First, based on the TCP protocol

Based on tcp socket, the key is two cycles, a cycle link, a communication cycle

socketserver module carved into two categories: server class (link to solve the problem) and request class (to solve the communication problems)

1.1 server class

1.2 request class

1.3 inheritance

1.4 server

import socketserver


class MyHandler(socketserver.BaseRequestHandler):
    def handle(self):
        # 通信循环
        while True:
            # print(self.client_address)
            # print(self.request) #self.request=conn

            try:
                data = self.request.recv(1024)
                if len(data) == 0: break
                self.request.send(data.upper())
            except ConnectionResetError:
                break


if __name__ == '__main__':
    s = socketserver.ThreadingTCPServer(('127.0.0.1', 8080), MyHandler, bind_and_activate=True)

    s.serve_forever()  # 代表连接循环
    # 循环建立连接，每建立一个连接就会启动一个线程（服务员）+调用Myhanlder类产生一个对象，调用该对象下的handle方法，专门与刚刚建立好的连接做通信循环

1.5 Client

import socket

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
phone.connect(('127.0.0.1', 8080))  # 指定服务端ip和端口

while True:
    # msg=input('>>: ').strip() #msg=''
    msg = 'client33333'  # msg=''
    if len(msg) == 0: continue
    phone.send(msg.encode('utf-8'))
    data = phone.recv(1024)
    print(data)

phone.close()

1.6 Client 1

import socket

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
phone.connect(('127.0.0.1', 8080))  # 指定服务端ip和端口

while True:
    # msg=input('>>: ').strip() #msg=''
    msg = 'client11111'  # msg=''
    if len(msg) == 0: continue
    phone.send(msg.encode('utf-8'))
    data = phone.recv(1024)
    print(data)

phone.close()

Second, based on the UDP protocol

2.1 server

import socketserver


class MyHandler(socketserver.BaseRequestHandler):
    def handle(self):
        # 通信循环
        print(self.client_address)
        print(self.request)

        data = self.request[0]
        print('客户消息', data)
        self.request[1].sendto(data.upper(), self.client_address)


if __name__ == '__main__':
    s = socketserver.ThreadingUDPServer(('127.0.0.1', 8080), MyHandler)
    s.serve_forever()

2.2 Client

import socket

client = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)  # 数据报协议-》udp

while True:
    # msg=input('>>: ').strip() #msg=''
    msg = 'client1111'
    client.sendto(msg.encode('utf-8'), ('127.0.0.1', 8080))
    data, server_addr = client.recvfrom(1024)
    print(data)

client.close()

2.3 Client 1

import socket

client = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)  # 数据报协议-》udp

while True:
    # msg=input('>>: ').strip() #msg=''
    msg = 'client2222'
    client.sendto(msg.encode('utf-8'), ('127.0.0.1', 8080))
    data, server_addr = client.recvfrom(1024)
    print(data)

client.close()

Three, socketserver source code analysis

ftpserver=socketserver.ThreadingTCPServer(('127.0.0.1', 8080)，FtpServer)
ftpserver.serve_forever()

• Find the Order of Attributes: ThreadingTCPServer-> ThreadingMixIn-> TCPServer-> BaseServer
  1. Examples of ftpserver obtained, first find the class ThreadingTCPServer the __init__, found in the TCPServer thereby carry server_bind, server_active
  2. Get serve_forever under ftpserver, BaseServer found, the execution further self._handle_request_noblock (), which is likewise in the BaseServer
  3. Performing self._handle_request_noblock () performs addition request, client_address = self.get_request ((TCPServer is in self.socket.accept ())), then perform self.process_request (request, client_address)
  4. Found in ThreadingMixIn process_request, open multiple threads to deal with concurrency, and then execute process_request_thread, execution self.finish_request (request, client_address)
  5. The four partially completed cycle links, this part of the communication processing section began to enter, find finish_request in BaseServer, the trigger instantiate our own definition of class, go __init__ method, and our own definition of the class does not have this method, to its parent class is in BaseRequestHandler find ....

3.1 Source summary

• Tcp-based class of socketserver our own definition of
  • self.server socket object that is
  • self.request that is a link
  • self.client_address namely client address
• Udp-based class of socketserver our own definition of
  • self.request is a tuple (a first element is the data sent by the client, the server is a second portion of udp socket object), such as (b'adsf ', <socket.socket fd = 200, family = AddressFamily.AF_INET, type = SocketKind.SOCK_DGRAM, proto = 0, laddr = ( '127.0.0.1', 8080)>)
  • self.client_address namely client address