【Python】简单的网络通信

简介

python实现简单的服务器和客户端实现，主要使用了struct、json、socket库。属于【深入理解RPC】基于Python自建分布式高并发RPC服务的练习文章小结

正题

交互规则

# 业务交互输入和输出(客户端和服务)
# 采用协议头长度划分业务
# | head(4byte) | data(...) |
# {
#   "in" : "ping"
#   "params" : "hello"
# }
#
# {
#   "out" : "pong"
#   "params" : "world"
# }

客户端

import json
import socket
import struct

def rpc(sock, handlers, handle):
    handlers[handle](sock)

def ping(sock):
    body = json.dumps({'in':'ping', 'params':'hello'})
    lenght_prefix = struct.pack('I', len(body))
    print(body, lenght_prefix)
    sock.sendall(lenght_prefix)
    sock.sendall(body.encode())

    #等待回复
    lenght_prefix = sock.recv(4)
    (length,) = struct.unpack('I', lenght_prefix)
    data = sock.recv(length)
    print(length, data)

if __name__ == '__main__':
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
        sock.connect(('localhost', 8080))
        handlers = {
            'ping': ping
        }
        rpc(sock, handlers,  'ping')

服务端

import json
import socket
import struct

def socket_connect(conn, addr, handlers, maps):
    with conn:
        print('connect :', addr)

        length_prefix = conn.recv(4)
        print(length_prefix)
        (length,) = struct.unpack('I', length_prefix)
        data = conn.recv(length)
        print(data)
        response = json.loads(data)
        handlers[maps[response['in']]](conn)

def pong(conn):
    # 回复
     body = json.dumps({'out': 'pong', 'params': 'world'})
     length_prefix = struct.pack('I', len(body))
     conn.sendall(length_prefix)
     conn.sendall(body.encode())

if __name__ == '__main__':
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
        sock.bind(('localhost', 8080))
        print('begin!')
        sock.listen(1)
        conn, addr = sock.accept()

        handlers = {        #调用函数表
            'pong': pong
        }

        maps = {            #客户端与服务操作映射表
            'ping' : 'pong'
        }
        socket_connect(conn, addr, handlers, maps)

通讯效果如下