解决粘包问题-终极版

server------------------

#!/usr/bin/env python
# encoding: utf-8  
# Date: 2018/6/5


import socket
import subprocess
import struct
import json

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
phone.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
phone.bind(('127.0.0.1', 8081))
phone.listen(5)

print('starting.......')
while True:  # 链接循环，保证客户端停止，服务端不停止，但是不支持并发
    conn, client_addr = phone.accept()
    print(client_addr)

    while True:
        try:  # window异常捕获
            # 1 接收命令
            cmd = conn.recv(1024)
            if not cmd:  # 适用于linux
                break  # 客户端断掉，发送空过来
            print('客户端的数据', cmd)
            # 2 执行命令，拿到结果
            obj = subprocess.Popen(cmd.decode('utf-8'), shell=True,
                                   stdout = subprocess.PIPE,
                                    stderr = subprocess.PIPE)
            stdout = obj.stdout.read()
            stderr = obj.stderr.read()
            # 3把命令的结果返回客户端
            # 第一步：制作固定长度的报头
            header_dic = {
                'filename': 'a.txt',
                'md5': 'xxdxx',
                'total_size': len(stdout) + len(stderr)
            }
            header_json = json.dumps(header_dic)

            header_bytes = header_json.encode('utf-8')

            # 第二步：先发送报头的长度
            conn.send(struct.pack('i', len(header_bytes)))
            # 第二步，发送报头
            conn.send(header_bytes)

            # 第三步，再发送真实的数据
            conn.send(stdout)
            conn.send(stderr)
        except ConnectionResetError:
            break
    conn.close()
phone.close()



client--------------------

#!/usr/bin/env python
# encoding: utf-8  
# Date: 2018/6/5


import socket
import struct
import json

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
phone.connect(('127.0.0.1', 8081))

while True:
    # 1发命令
    cmd = input('>>>:').strip()
    if not cmd:continue
    phone.send(cmd.encode('utf-8')) # 应用程序发给操作系统，操作系统调用网卡
    # 那命令结果
    #  第一步：先收报头长度
    obj = phone.recv(4)
    header_size = struct.unpack('i', obj)[0]

    # 第二步：收报头
    header_bytes = phone.recv(header_size)
    # 第三步：从报头中解析出对真实数据的描述信息
    header_json = header_bytes.decode('utf-8')
    header_dic = json.loads(header_json)
    total_size = header_dic['total_size']
    # 第三步：接收真实的数据
    recv_size = 0
    recv_data = b''
    while recv_size < total_size:
        res = phone.recv(1024)
        recv_data += res
        recv_size += len(res)
    print(res.decode('utf-8'))

phone.close()