Python-socket发送文件并解决粘包问题

Posted 2020-10-24 Sch01aR#

服务器端要先根据客户端要下载的文件进行判断是否存在，还要根据文件大小来进行传送，最后还要比对文件的md5值来判断传送的文件是否正确，通过判断剩余字节来解决粘包问题

服务器端

# -*- coding:utf-8 -*-
__author__ = "MuT6 Sch01aR"

import socket
import os
import hashlib

server = socket.socket()
server.bind((\'127.0.0.1\',8080))
server.listen()
print(\'等待客户端连接\')

while True:
    conn,addr = server.accept()
    print(\'当前连接客户端：\',addr)
    while True:
        print(\'等待客户端下载指令\')
        data = conn.recv(1024)
        if not data:
            print(\'客户端已断开连接\')
            break
        filename = data.decode()
        if os.path.isfile(filename): #判断文件是否存在
            f = open(filename,\'rb\')
            m = hashlib.md5()
            file_size = os.stat(filename).st_size #获取文件大小
            conn.send(str(file_size).encode()) #发送文件大小
            conn.recv(1024) #等待确认
            for line in f:
                conn.send(line) #发送文件
                m.update(line)
            print("文件md5值：", m.hexdigest())
            conn.send(m.hexdigest().encode())  #发送md5值
            f.close()
        print(\'发送完成\')
server.close()

客户端

# -*- coding:utf-8 -*-
__author__ = "MuT6 Sch01aR"

import socket
import hashlib

client = socket.socket()
client.connect((\'127.0.0.1\',8080))

while True:
    cmd = input(\'请输入需要下载的文件:\').strip()
    client.send(cmd.encode())
    if len(cmd) == 0:continue
    server_file_size = client.recv(1024)
    client.send(\'准备好接收文件了\'.encode())

    server_file_size = int(server_file_size.decode()) #要接收的文件大小
    received_size = 0

    filename = cmd
    f = open(filename+\'_new\',\'wb\')

    m = hashlib.md5()

    while received_size < server_file_size:
        if server_file_size - received_size >1024: #判断要接收的次数是否大于一次
            left_size = 1024
        else:
            left_size = server_file_size - received_size
        data = client.recv(left_size)
        received_size += len(data)
        m.update(data)
        f.write(data)
    else:
        new_file_md5 = m.hexdigest()
        print(\'下载完成\',received_size,server_file_size)
        f.close()
    server_file_md5 = client.recv(1024)
    if new_file_md5.encode() == server_file_md5:
        print(\'下载文件正确\')
    else:
        print(\'下载了错误文件\')

client.close()

运行结果

服务器端

文件传输结果