Python编程：socket实现文件传输

# 服务器端
import socket
import os
import hashlib
server = socket.socket()
server.bind(("localhost", 6969)) # 绑定监听端口
server.listen(5)  # 监听
print("监听开始..")
while True:
    conn, addr = server.accept()  # 等待连接
    print("conn:", conn, "\naddr:", addr)  # conn连接实例
    while True:
        data = conn.recv(1024)  # 接收
        if not data:  # 客户端已断开
            print("客户端断开连接")
            break
        print("收到的命令：", data.decode("utf-8"))
        cmd, filename = data.decode("utf-8").split(" ")
        if cmd =="get":
            if os.path.isfile(filename):  # 判断文件存在
                # 1.先发送文件大小，让客户端准备接收
                size = os.stat(filename).st_size  #获取文件大小
                conn.send(str(size).encode("utf-8"))  # 发送数据长度
                print("发送的大小：", size)
                # 2.发送文件内容
                conn.recv(1024)  # 接收确认
                m = hashlib.md5()
                f = open(filename, "rb")
                for line in f:
                    conn.send(line)  # 发送数据
                    m.update(line)
                f.close()
                # 3.发送md5值进行校验
                md5 = m.hexdigest()
                conn.send(md5.encode("utf-8"))  # 发送md5值
                print("md5:", md5)
server.close()

# 客户端
import socket
import os
import hashlib
client = socket.socket()  # 生成socket连接对象
ip_port =("localhost", 6969)  # 地址和端口号
client.connect(ip_port)  # 连接
print("服务器已连接")
while True:
    content = input(">>")
    if len(content)==0: continue  # 如果传入空字符会阻塞
    if content.startswith("get"):
        client.send(content.encode("utf-8"))  # 传送和接收都是bytes类型
        # 1.先接收长度，建议8192
        server_response = client.recv(1024)
        file_size = int(server_response.decode("utf-8"))
        print("接收到的大小：", file_size)
        # 2.接收文件内容
        client.send("准备好接收".encode("utf-8"))  # 接收确认
        filename = "new" + content.split(" ")[1]
        f = open(filename, "wb")
        received_size = 0
        m = hashlib.md5()
        while received_size < file_size:
            size = 0  # 准确接收数据大小，解决粘包
            if file_size - received_size > 1024: # 多次接收
                size = 1024
            else:  # 最后一次接收完毕
                size = file_size - received_size
            data = client.recv(size)  # 多次接收内容，接收大数据
            data_len = len(data)
            received_size += data_len
            print("已接收：", int(received_size/file_size*100), "%")
            m.update(data)
            f.write(data)
        f.close()
        print("实际接收的大小:", received_size)  # 解码
        # 3.md5值校验
        md5_sever = client.recv(1024).decode("utf-8")
        md5_client = m.hexdigest()
        print("服务器发来的md5:", md5_sever)
        print("接收文件的md5:", md5_client)
        if md5_sever == md5_client:
            print("MD5值校验成功")
        else:
            print("MD5值校验失败")
client.close()

get filename