使用 Socket 實現 FTP Server ，實現如下功能：

get /tmp/1.txt /tmp/1.txt ：把服務端 /tmp/1.txt 下載到客戶端 /tmp/1.txt
put /tmp/1.txt /tmp/1.txt ：把客戶端 /tmp/1.txt 上傳到服務端 /tmp/1.txt

[root@localhost ~]# cat ftp_server.py 
#!/usr/bin/env python
#-*- coding: utf8 -*-

import socket
from subprocess import Popen, PIPE

HOST = ‘‘
PORT 
 
= 1234
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
print ‘conn‘, conn
print ‘Connected by‘, addr
while 1:
    cmd = conn.recv(1024)
    cmd_list = cmd.split()
    if cmd_list[0] == ‘get‘:
        with open(cmd_list[1]) as fd:
            
 
while True:
                data = fd.read(1024)
                conn.sendall(data)
                if not data:
                    conn.sendall(‘EOF‘)
                    break
    if not cmd: break
conn.close()

[root@localhost ~]# cat ftp_client.py 
#!/usr/bin/env python
#-*- coding:utf-8
 
 -*-

import os
import sys
import tab
import socket

HOST = ‘192.168.5.131‘
PORT = 1234
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
while True:
    cmd = raw_input("Please input cmd: ").strip()
    if cmd.lower()== ‘exit‘ or cmd.lower() == ‘quit‘:
        break
    cmd_list = cmd.split()
    if len(cmd_list) != 3:
        print "Ex: get file1 file2"
        continue
    else:
        s.sendall(cmd)
        if not os.path.exists(cmd_list[2]):
            dst_file = cmd_list[2]
        else:
            dst_file = cmd_list[2]+‘.new‘
        n = 1
        while True:
            data_rev = s.recv(1024)
            if data_rev.endswith(‘EOF‘):
                data = data_rev[:-3]
            else:
                data = data_rev
            if n == 1:
                with open(dst_file, ‘wb‘) as fd:
                    fd.write(data) 
            else:
                with open(dst_file, ‘a‘) as fd:
                    fd.write(data)
            n += 1
            if data_rev[-3:] == ‘EOF‘:
                print "Success! destination file is %s" % dst_file
                break
s.close()

使用 Socket 實現 FTP Server