基于tcp协议通信的套接字

一. 基于tcp协议通信的套接字(通信循环+链接循环)

服务端代码

from socket import *

server = socket(AF_INET, SOCK_STREAM)
server.bind(('127.0.0.1', 8080))
server.listen(5)

# 链接循环
while True:
    conn, client_addr = server.accept()
    print(client_addr)

    # 通信循环
    while True:
        try:
            data = conn.recv(1024)
            if len(data) == 0: break  # 针对linux系统
            print('-->收到客户端的消息: ', data)
            conn.send(data.upper())
        except ConnectionResetError:
            break

    conn.close()

server.close()

客户端代码

from socket import *

client = socket(AF_INET, SOCK_STREAM)
client.connect(('127.0.0.1', 8080))

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

client.close()

二. 远程执行命令的程序

服务端代码

from socket import *
import subprocess

server = socket(AF_INET, SOCK_STREAM)
server.bind(('127.0.0.1', 8080))
server.listen(5)

# 链接循环
while True:
    conn, client_address = server.accept()
    print(client_address)

    # 通信循环
    while True:
        try:
            cmd = conn.recv(1024)  
            if len(cmd) == 0: break  # 针对linux系统
            obj = subprocess.Popen(cmd.decode('utf-8'),
                                   shell=True,
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE
                                   )
            stdout = obj.stdout.read()
            stderr = obj.stderr.read()
            print(len(stdout) + len(stderr))
            conn.send(stdout + stderr)
        except ConnectionResetError:
            break

    conn.close()

server.close()

客户端代码

from socket import *

client = socket(AF_INET, SOCK_STREAM)
client.connect(('127.0.0.1', 8080))

# 通信循环
while True:
    cmd = input('>>: ').strip()
    if len(cmd) == 0: continue
    client.send(cmd.encode('utf-8'))
    cmd_res = client.recv(1024)
    print(cmd_res.decode('gbk'))

client.close()

三. 模拟ssh实现远程执行命令(解决粘包问题)

服务端代码

from socket import *
import subprocess, json, struct

server = socket(AF_INET, SOCK_STREAM)
server.bind(('127.0.0.1', 8081))
server.listen(5)

# 链接循环
while True:
    conn, client_addr = server.accept()
    print(client_addr)

    # 通信循环
    while True:
        try:
            cmd = conn.recv(1024)
            if len(cmd) == 0: break  # 针对linux系统
            obj = subprocess.Popen(cmd.decode('utf-8'),
                                   shell=True,
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE
                                   )
            stdout = obj.stdout.read()
            stderr = obj.stderr.read()
            # 1. 先制作报头
            header_dic = {
                'filename': 'a.txt',
                'md5': 'asdfasdf123123x1',
                'total_size': len(stdout) + len(stderr)
            }
            header_json = json.dumps(header_dic)
            header_bytes = header_json.encode('utf-8')

            # 2. 先发送4个bytes(包含报头的长度)
            conn.send(struct.pack('i', len(header_bytes)))
            # 3  再发送报头
            conn.send(header_bytes)

            # 4. 最后发送真实的数据
            conn.send(stdout)
            conn.send(stderr)
        except ConnectionResetError:
            break

    conn.close()

server.close()

客户端代码

from socket import *
import struct,json

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

# 通信循环
while True:
    cmd=input('>>: ').strip()
    if len(cmd) == 0:continue
    client.send(cmd.encode('utf-8'))
    #1. 先收4bytes,解出报头的长度
    header_size=struct.unpack('i',client.recv(4))[0]

    #2. 再接收报头,拿到header_dic
    header_bytes=client.recv(header_size)
    header_json=header_bytes.decode('utf-8')
    header_dic=json.loads(header_json)
    print(header_dic)
    total_size=header_dic['total_size']

    #3. 接收真正的数据
    cmd_res=b''
    recv_size=0
    while recv_size < total_size:
        data=client.recv(1024)
        recv_size+=len(data)
        cmd_res+=data

    print(cmd_res.decode('gbk'))

client.close()