Python--select版的FTP

Posted 2020-10-15

1、要求

用select模块实现FTP上传文件和下载文件的功能

2、目录

3、实现，主要修改的还是server的代码

client端

 1 import socket
 2 import os
 3 from lib import *
 4 
 5 def download():
 6     msg = ‘download ‘
 7     #显示要下载的目录中的文件
 8     filename=input(‘输入你要下载的文件名（保存到当前路径）‘)
 9     msg +=filename
10     return msg
11 
12 def upload():
13     msg=‘upload ‘
14     filedir=input("输入你要上传的文件路径")
15     filename=filedir.split(‘\\\\‘)[-1]
16     msg += filename+‘ ‘
17     with open(filedir,‘r‘) as fd:
18         msg +=fd.read()
19     return msg
20 
21 def bye():
22     msg=‘exit‘
23     return msg
24 
25 def showfile():
26     msg=‘currentfiles‘
27     client.send(msg.encode(‘utf-8‘))
28     reply=client.recv(1024).decode(‘utf-8‘)
29     print(reply)
30     print("您可以从download目录下载需要的文件，保存在当前工作目录，或上传文件至upload目录。")
31     return
32 
33 def storefile():
34     filename = input("请输入要保存的名字：")
35     filepath = os.path.join(os.getcwd(), filename)
36     with open(filepath, ‘w‘) as fd:
37         fd.write(reply)
38     return
39 
40 client=socket.socket()
41 client.connect((‘localhost‘,21))
42 ftprequest={‘1‘:download,‘2‘:upload,‘3‘:bye}
43 
44 while True:
45     showfile()
46     incmd = input("你要干嘛？\\n1、下载文件\\n2、上传文件\\n3、退出")
47     if incmd in ftprequest.keys():
48         mess=ftprequest[incmd]()
49         client.send(mess.encode(‘utf-8‘))
50         if mess==‘exit‘:
51             break
52         reply = client.recv(1024).decode(‘utf-8‘)
53         if incmd==‘1‘:
54             storefile()
55 client.close()

server端

 1 import socket
 2 import os
 3 import select
 4 import queue
 5 from lib import *
 6 
 7 def showfiles():
 8     curdir = pathdefine.downloaddir
 9     returnstr = ‘‘
10     for root, dirs, files in os.walk(curdir):
11         returnstr += ‘rootdir:‘ + root + ‘\\n‘
12         for d in dirs:
13             returnstr += ‘directory:‘ + d + ‘\\n‘
14         for f in files:
15             returnstr += ‘file:‘ + f + ‘\\n‘
16     print(returnstr)
17     conn.send(returnstr.encode(‘utf-8‘))
18     return
19 
20 #建立服务器socket、绑定、监听
21 server=socket.socket()
22 server.bind((‘127.0.0.1‘,21))
23 server.listen(100)
24 server.setblocking(False)
25 
26 inputs = [server, ] #自己也要监测呀,因为server本身也是个fd
27 outputs = []
28 
29 message_queues = {}
30 
31 while True:
32     print("waiting for next event...")
33 
34     readable, writeable, exeptional = select.select(inputs,outputs,inputs) #如果没有任何fd就绪,那程序就会一直阻塞在这里
35 
36     for s in readable: #每个s就是一个socket
37 
38         if s is server:
39             conn, client_addr = s.accept()
40             print("new connection from",client_addr)
41             conn.setblocking(False)
42             inputs.append(conn)
43         else:
44             data = s.recv(1024)
45             if data:
46                 datastr=data.decode(‘utf-8‘)
47                 if datastr==‘exit‘:
48                     if s in outputs:
49                         outputs.remove(s)
50                     inputs.remove(s)
51                     del message_queues[s]
52                 elif datastr == ‘currentfiles‘:
53                     showfiles()
54                 elif datastr.startswith(‘download‘):
55                     strlist = datastr.split()
56                     filename = strlist[1]
57                     dirname = os.path.join(pathdefine.downloaddir, filename)
58                     with open(dirname, ‘r‘) as fd:
59                         msg = fd.read()
60                     conn.send(msg.encode(‘utf-8‘))
61                 elif datastr.startswith(‘upload‘):
62                     strlist = datastr.split()
63                     filename = strlist[1]
64                     filecont = strlist[2]
65                     dir = os.path.join(pathdefine.uploaddir, filename)
66                     with open(dir, ‘w‘) as fd:
67                         fd.write(filecont)
68                     conn.send(b‘***‘)
69             else:#如果收不到data代表什么呢? 代表客户端断开了呀
70                 print("客户端断开了",s)
71                 if s in outputs:
72                     outputs.remove(s) #清理已断开的连接
73                 inputs.remove(s) #清理已断开的连接
74     for s in exeptional:
75         print("handling exception for ",s.getpeername())
76         inputs.remove(s)
77         if s in outputs:
78             outputs.remove(s)
79         s.close()