文件断点续传的理解与实现（2）

先来一张图理解断点续传：

 项目搭建：

服务端：

#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
实现文件断点续传的服务器端
"""

import socket
import os

BASE_DIR = os.path.dirname(os.path.dirname(__file__))

home = os.path.join(BASE_DIR, "home/file")
sk = socket.socket()
sk.bind(('127.0.0.1', 8001))
sk.listen(5)

while True:
    print("Waiting....")
    conn, addr = sk.accept()
    conn.sendall(bytes('欢迎登录', encoding='utf-8'))
    flag = True
    while flag:
        client_bytes = conn.recv(1024)   #接收客户端发送过来的内容
        client_str = str(client_bytes, encoding='utf-8')  #将内容转换成字符串

        # 将客户端发送过来的内容以"|"拆分为:命名方法，文件名，文件大小，目标路径
        func, file_name, file_byte_size, targe＿path = client_str.split('|', 3)
        file_byte_size = int(file_byte_size)
        path = os.path.join(home, file_name)
        has_received = 0
        #首先判断该路径下是否已存在文件
        if os.path.exists(path):
            conn.sendall(bytes("2003", encoding='utf-8'))  #发送通知客户端，该文件已存在
            is_continue = str(conn.recv(1024), encoding='utf-8')  #等待客户端选择回复
            if is_continue == "2004":
                has_file_size = os.stat(path).st_size
                conn.sendall(bytes(str(has_file_size), encoding='utf-8'))  #将已接收的文件大小给客户端
                has_received += has_file_size
                f = open(path, 'ab')
            else:
                f = open(path, 'wb')
        else:
            conn.sendall(bytes("2002", encoding='utf-8'))
            f = open(path, 'wb')

        while has_received < file_byte_size:
            try:
                data = conn.recv(1024)
                if not data:
                    raise Exception
            except Exception:
                flag = False
                break
            f.write(data)
            has_received += len(data)
        print("文件已接收完成！")
        f.close()

client

#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
实现文件断点续传的客户端
"""

import socket
import sys
import re
import os
FILE_DIR = os.path.dirname(__file__)

ck = socket.socket()
ck.connect(('127.0.0.1', 8001))
print(str(ck.recv(1024), encoding='utf-8'))


#定义一个函数，计算进度条
def bar(num = 1, sum = 100):
    rate = float(num) / float(sum)
    rate_num = int(rate * 100)
    temp = '
%d %%' % (rate_num)
    sys.stdout.write(temp)

while True:
    inp = input('请输入（内容格式：post|文件路径 目标路径）: 
 >>> ').strip()  #输入内容格式：命令|文件路径 目标路径
    func, file_path =inp.split("|", 1)  #将输入的内容拆分为两部分，方法名和路径
    local_path, target_path = re.split("s*", file_path, 1) #再将路径部分，通过正则表达式。以空格拆分为：文件路径和上传的目标路径,s*表示匹配任意个空格
    file_byte_size = os.stat(local_path).st_size  #获取文件的大小
    file_name = os.path.basename(local_path)   #设置文件名

    post_info = "post|%s|%s|%s" % (file_name, file_byte_size, target_path)  #将发送的内容进行拼接
    ck.sendall(bytes(post_info, encoding='utf-8'))  #向服务器端发送内容

    result_exist = str(ck.recv(1024), encoding='utf-8')
    has_sent = 0
    if result_exist == "2003":
        inp = input("文件已存在，是否续传？Y/N:").strip()
        if inp.upper() == 'Y':
            ck.sendall(bytes("2004", encoding='utf-8'))
            result_continue_pos = str(ck.recv(1024), encoding='utf-8')  #已经传输了多少的文件内容
            print(result_continue_pos)
            has_sent = int(result_continue_pos)

        else:
            ck.sendall(bytes("2005", encoding='utf-8'))  #发送2005代表不续传

    file_obj = open(local_path, 'rb')  #对文件进行读操作
    file_obj.seek(has_sent)  #调整指针

    while has_sent < file_byte_size:
        data = file_obj.read(1024)
        ck.sendall(data)
        has_sent += len(data)
        bar(has_sent, file_byte_size)  #进度条

    file_obj.close()
    print("文件上传成功！")