import socket

 import os

 import time

 import hashlib

 server = socket.socket()

 server.bind(('localhost',3333))

 server.listen()

 while True:

     conn,addr = server.accept()

     print("new conn:",addr)

     while True:

         print("等待新指令")

         data = conn.recv(1024)

         if not data:

             print("客户端已断开")

             break

         cmd,filename = data.decode().split()

         print(filename)

         if os.path.isfile(filename):

             f = open(filename,"rb")

             m = hashlib.md5()

             file_size = os.stat(filename).st_size  #在os模块中获取文件大小

             conn.send(str(file_size).encode())   #发送文件大小

             conn.recv(1024)   #wait  for ack

             for line in f:

                 m.update(line)

                 conn.send(line)

             print("file md5",m.hexdigest())

             f.close()

             conn.send(m.hexdigest().encode()) #send md5

         print("执行指令：", data)

 server.close()

 import socket

 import hashlib

 client = socket.socket()

 client.connect(('localhost',3333))

 while True:

     cmd = input(">>:").strip()   #cmd = input(b">>:").strip()如果前面直接加b，则只能传英文

     if len(cmd) == 0 : continue

     if cmd.startswith("get"):

         client.send(cmd.encode())

         server_response = client.recv(1024)

         print("server response:",server_response)

         client.send("ready to recv file".encode())

         file_total_size = int(server_response.decode())

         received_size = 0

         filename = cmd.split()[1]

         f = open("wenjian","wb")

         m = hashlib.md5()

         while received_size<file_total_size:

             #下面这段代码彻底解决粘包问题

             if file_total_size - received_size > 1024:  #要收不止一次

                 size = 1024

             else:

                 size = file_total_size - received_size #最后一次了，剩多少收多少

                 print("last receive:",size)

             data = client.recv(1024)

             received_size += len(data)

             m.update(data)

             f.write(data)

             print(file_total_size,received_size)  #看演示效果

         else:

             new_file_md5 = m.hexdigest()

             print("file received done",received_size,file_total_size)

             f.close()

         server_file_md5 = client.recv(1024)

         print("server file md5:",server_file_md5)

         print("client file md5:", new_file_md5)

 client.close()