python2.7实现FTP文件下载功能

#-*-coding:utf-8-*- 
 
 
import os 
import time 
from ftplib import FTP 
 
 
#服务器地址 
FTP_SERVER='xx.xx.xx.xx' -- 对应 ftpe服务器地址 
USER='用户' 
PWD ='密码' 
FTP_PATH='/home/xx/xx/' 
local_root='e:'+FTP_PATH 
DATE= time.strftime('%Y%m%d',time.localtime(time.time())) 
print DATE 
 
def isDir(filename): 
 try: 
 path = filename; 
 path.replace('/','\\') 
 if os.path.exists(path): 
  print '---file exists--' 
 else: 
  print 'file not exists ',local_root 
  os.mkdirs(local_root)  
 return True 
 except: 
 return False 
 
 
def ftpconnect(): 
 ftp=FTP() 
 ftp.set_debuglevel(2) 
 ftp.connect(FTP_SERVER,21) 
 ftp.login(USER,PWD) 
 return ftp 
 
 
def downloadfile(): 
 ftp = ftpconnect() 
 print ftp.getwelcome() #显示ftp服务器欢迎信息 
 
 li = ftp.nlst(FTP_PATH) 
 print 'ftp: ',li 
 for eachfile in li: 
 localpath = 'e:'+eachfile 
 print '-- open localpath --',localpath 
 bufsize = 1024 
 isDir(localpath) 
 fp = open(localpath,'wb+') 
 ftp.retrbinary('RETR '+eachfile,fp.write,bufsize) 
 fp.flush() 
 
 ftp.set_debuglevel(0) #关闭调试 
 fp.close() 
 ftp.quit() #退出ftp服务器 
 
if __name__=="__main__": 
 downloadfile()