python ftp上传下载文件，支持断点续传

功能：ftp断点上传下载

仅供参考:

#encoding=utf-8
'''
Created on 2012-3-14

@author: cooler
'''
from ftplib import FTP  
import sys  
import os.path  
  
class MyFTP(FTP):  
    ''''' 
    conncet to FTP Server 
    '''  
    def __init__(self):
        print 'make a object'
    def ConnectFTP(self,remoteip,remoteport,loginname,loginpassword):  
        ftp=MyFTP()

        try:
            ftp.connect(remoteip,remoteport,600)
            print 'success'
        except:
            print "conncet failed1"
            return (0,'conncet failed')  
        else:  
            try:  
                ftp.login(loginname,loginpassword)  
                print 'login success'
            except:  
                print 'login failed'
                return (0,'login failed')  
            else:  
                print 'return 1'
                return (1,ftp)  
      
    def download(self,remoteHost,remotePort,loginname,loginpassword,remotePath,localPath):  
        #connect to the FTP Server and check the return  
        res = self.ConnectFTP(remoteHost,remotePort,loginname,loginpassword)  
        if(res[0]!=1):  
            print res[1]  
            sys.exit()  
          
        #change the remote directory and get the remote file size  
        ftp=res[1]  
        ftp.set_pasv(0)  
        dires = self.splitpath(remotePath)  
        if dires[0]:  
            ftp.cwd(dires[0])  
        remotefile=dires[1]  
        print dires[0]+' '+ dires[1]  
        fsize=ftp.size(remotefile)  
        if fsize==0 :  
            return  
          
        #check local file isn't exists and get the local file size  
        lsize=0L  
        if os.path.exists(localPath):  
            lsize=os.stat(localPath).st_size  
              
        if lsize >= fsize:  
            print 'local file is bigger or equal remote file'  
            return  
        blocksize=1024  
        cmpsize=lsize  
        ftp.voidcmd('TYPE I')  
        conn = ftp.transfercmd('RETR '+remotefile,lsize)  
        lwrite=open(localPath,'ab')
        while True:  
            data=conn.recv(blocksize)  
            if not data:  
                break  
            lwrite.write(data)  
            cmpsize+=len(data)  
            print '\b'*30,'download process:%.2f%%'%(float(cmpsize)/fsize*100),  
        lwrite.close()  
        ftp.voidcmd('NOOP')  
        ftp.voidresp()  
        conn.close()  
        ftp.quit()  
      
    def upload(self,remotehost,remoteport,loginname,loginpassword,remotepath,localpath,callback=None):  
        if not os.path.exists(localpath):  
            print "Local file doesn't exists"  
            return  
        self.set_debuglevel(2)  
        res=self.ConnectFTP(remotehost,remoteport,loginname,loginpassword)  
        if res[0]!=1:  
            print res[1]  
            sys.exit()  
        ftp=res[1]  
        remote=self.splitpath(remotepath)  
        ftp.cwd(remote[0])  
        rsize=0L  
        try:  
            rsize=ftp.size(remote[1])  
        except:  
            pass  
        if (rsize==None):  
            rsize=0L  
        lsize=os.stat(localpath).st_size  
        if (rsize==lsize):  
            print 'remote filesize is equal with local'  
            return  
        if (rsize<lsize):  
            localf=open(localpath,'rb')  
            localf.seek(rsize)  
            ftp.voidcmd('TYPE I')  
            datasock,esize=ftp.ntransfercmd("STOR "+remote[1],rsize)  
            cmpsize=rsize  
            while True:  
                buf=localf.read(1024)  
                if not len(buf):  
                    print '\rno data break'  
                    break  
                datasock.sendall(buf)  
                if callback:  
                    callback(buf)  
                cmpsize+=len(buf)  
                print '\b'*30,'uploading %.2f%%'%(float(cmpsize)/lsize*100),  
                if cmpsize==lsize:  
                    print '\rfile size equal break'  
                    break  
            datasock.close()  
            print 'close data handle'  
            localf.close()  
            print 'close local file handle'  
            ftp.voidcmd('NOOP')  
            print 'keep alive cmd success'  
            ftp.voidresp()  
            print 'No loop cmd'  
            ftp.quit()  
              
          
    def splitpath(self,remotepath):  
        position=remotepath.rfind('/')  
        return (remotepath[:position+1],remotepath[position+1:])  
        
          
if __name__=='__main__':  
    lf = MyFTP()
    lf.ConnectFTP("192.168.100.237","21","cooler","123123")
    lf.download("192.168.100.237","21","cooler","123123","/tmp/cooler/boke.rar","C:/cooler/boke.rar")
    lf.upload("192.168.100.237","21","cooler","123123","/tmp/cooler/boke1.rar","C:/cooler/boke.rar")