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

#!/usr/bin/env python

# encoding: utf-8  

# Date: 2018/6/7

import socket

import os

import json

import struct

shar_dir = r'E:\python\PycharmProjects\python.base.demo\model3\socket1\上传下载\简单版本\server\share'

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

phone.bind(('127.0.0.1', 9909))

phone.listen(5)

print('starting...')

while True:

    conn,client_addr = phone.accept()

    print(client_addr)

    while True:

        try:

            # 1收命令

            res = conn.recv(8096)  # b'get a.txt'

            if not res:break

            # 2,解析命令，提取相应命令参数

            cmds = res.decode('utf-8').split()  # ['get',filename]

            filename = cmds[1]

            # 3,易读的方式打开文件，读取文件内容发送给客户端

            header_dic = {

                'filename': filename,

                'md5':'xxxdxxx',

                'file_size': os.path.getsize(r'%s\%s' % (shar_dir, filename))

            }

            header_json = json.dumps(header_dic)

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

            # 2,先发送报头的长度

            conn.send(struct.pack('i', len(header_bytes)))

            # 3,再发报头

            conn.send(header_bytes)

            # 4,再发送真实的数据

            with open('%s\%s' % (shar_dir, filename), 'rb') as f:

                # conn.send(f.read())

                for line in f:

                    conn.send(line)

        except ConnectionResetError:

            break

    conn.close()

phone.close()

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

#!/usr/bin/env python

# encoding: utf-8  

# Date: 2018/6/7

import socket

import struct

import json

dow_dir = r'E:\python\PycharmProjects\python.base.demo\model3\socket1\上传下载\简单版本\client\download'

phone = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

phone.connect(('127.0.0.1', 9909))

while True:

    # 1,发命令

    cmd = input('>>:').strip()

    if not cmd:continue

    phone.send(cmd.encode('utf-8'))

    # 2,以写的方式打开一个新文件

    # 2.1收报头长度

    obj = phone.recv(4)

    header_size = struct.unpack('i', obj)[0]

    # 2.2收报头

    header_bytes = phone.recv(header_size)

    # 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)

    print(header_dic)

    total_size = header_dic['file_size']

    filename = header_dic['filename']

    # 2.4,接收真实的数据

    with open('%s\%s' % (dow_dir, filename), 'wb') as f:  #  服务端打开读方式，这里这种wb方式容易卡主

        recv_size = 0

        while recv_size < total_size:

            line = phone.recv(1024)

            f.write(line)

            recv_size += len(line)

            print('总大小:%s 已下载大小： %s' % (total_size, recv_size))

phone.close()