Python3实现TFTP文件传输服务器与客户端详解

from socket import *
import os
import signal
import sys
import time

# 文件库路径 
FILE_PATH = "/home/tarena/" 

class TftpServer(object): 
 def __init__(self, connfd): 
  self.connfd = connfd 
 
 def do_list(self): 
  # 获取列表 
  file_list = os.listdir(FILE_PATH) 
  # 如果对应的路径内没有文件,返回Empty 
  if not file_list: 
   self.connfd.send('Empty'.encode()) 
   return 
  # 路径存在文件,向客户端发送OK 
  else: 
   self.connfd.send(b'OK') 
   time.sleep(0.1) 
 
  files = "" 
  for file in file_list: 
   # 排除以'.'开头的隐藏文件 
   if file[0] != '.' and \ 
     os.path.isfile(FILE_PATH + file): 
    files = files + file + '#' 
  # 返回文件列表 
  self.connfd.send(files.encode()) 
 
 # 下载文件功能 
 def do_get(self, filename): 
  try: 
   fd = open(FILE_PATH + filename, 'rb') 
  except: 
   self.connfd.send("File doesn't exist".encode()) 
   return 
  # 如果能正常打开,发送OK 
  self.connfd.send(b"OK") 
  time.sleep(0.1) 
  # 开始发送文件 
  try: 
   for line in fd: 
    self.connfd.send(line) 
   fd.close() 
  except Exception as e: 
   print(e) 
  time.sleep(0.1) 
  self.connfd.send(b'##') 
  print("File send over") 
 
 # 开始上传文件 
 def do_put(self, filename): 
  try: 
   fd = open(FILE_PATH + filename, 'w') 
  except: 
   self.connfd.send("Some error") 
  # 如果能正常打开文件,则发送OK 
  self.connfd.send(b'OK') 
  # 开始发送 
  while True: 
   # data为文件内容 
   data = self.connfd.recv(1024).decode() 
   if data == "##": 
    break 
   fd.write(data) 
  fd.close() 
  print("上传完毕") 

def main():
 # 创建套接字/地址/端口
 HOST = '0.0.0.0'
 PORT = 8888
 ADDR = (HOST, PORT)

 sockfd = socket()
 # 设置端口可重用
 sockfd.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
 # 绑定地址
 sockfd.bind(ADDR)
 # 设置监听队列大小
 sockfd.listen(5)

 signal.signal(signal.SIGCHLD, signal.SIG_IGN)
 print("Listen to port 8888....")

 while True:
  try:
   connfd, addr = sockfd.accept()
  except KeyboardInterrupt:
   sockfd.close()
   sys.exit("Server exit")
  except Exception as e:
   print(e)
   continue
  print("Client login:", addr)
  # 创建父子进程
  pid = os.fork()
  if pid < 0:
   print("Process creation failed")
   continue
  elif pid == 0:
   # 子进程负责请求接收和发送,所以节省资源,关闭连接套字
   sockfd.close()
   tftp = TftpServer(connfd)
   # 接收客户端请求
   while True:
    data = connfd.recv(1024).decode()
    if not data:
     continue
    # 调用do_list方法获取文件列表
    elif data[0] == 'L':
     tftp.do_list()
    # data ==> G filename
    # 文件名以G开头,以空格为间隔发送过来
    elif data[0] == 'G':
     filename = data.split(' ')[-1]
     tftp.do_get(filename)
    elif data[0] == 'P':
     filename = data.split(' ')[-1]
     tftp.do_put(filename)
    elif data[0] == 'Q':
     print("客户端退出")
     sys.exit(0)

  else:
   connfd.close()
   continue

if __name__ == "__main__": 
 main() 

from socket import * 
import sys 
import time 

class TftpServer(object):
 def __init__(self, sockfd):
  self.sockfd = sockfd

 def do_list(self):
  self.sockfd.send(b"L") # 发送请求类型
  # 等待接收服务器端确认
  data = self.sockfd.recv(1024).decode()
  if data == 'OK':
   data = self.sockfd.recv(4096).decode()
   files = data.split('#')
   for file in files:
    print(file)
   print("%%%%%There is file list%%%%%\n")
  else:
   # 失败的原因由服务器发送过来
   print(data)

 def do_get(self, filename):
  self.sockfd.send(('G '+filename).encode())
  data = self.sockfd.recv(1024).decode()
  if data == 'OK':
   fd = open(filename, 'w')
   while True:
    data = self.sockfd.recv(1024).decode()
    if data == "##":
     break
    fd.write(data)
   fd.close()
   print("%s Download over\n" % filename)
  else:
   print(data)

 def do_put(self, filename):
  try:
   fd = open(filename, 'rb')
  except:
   print("There is no such file")
   return
  self.sockfd.send(("P " + filename).encode())
  data = self.sockfd.recv(1024).decode()
  if data == 'OK':
   for line in fd:
    self.sockfd.send(line)
   fd.close()
   time.sleep(0.1)
   self.sockfd.send(b'##')
   print("%s upload over" % filename)
  else:
   print(data)

 def do_quit(self):
  self.sockfd.send(b'Q')

# 套接字连接
def main():
 if len(sys.argv) < 3:
  print("argv is error")
  return
 HOST = sys.argv[1]
 PORT = int(sys.argv[2])
 ADDR = (HOST, PORT)

 sockfd = socket()
 sockfd.connect(ADDR)

 tftp = TftpServer(sockfd) # tftp对象调用请求方法

 while True:
  print("=======命令选项========")
  print("******* list *********")
  print("*******get file ******")
  print("*******put file ******")
  print("******* quit *********")
  print("======================")

  cmd = input("请输入命令>>")

  if cmd.strip() == 'list':
   tftp.do_list()
  elif cmd[:3] == "get":
   filename = cmd.split(' ')[-1]
   tftp.do_get(filename)
  elif cmd[:3] == "put":
   filename = cmd.split(' ')[-1]
   tftp.do_put(filename)
  elif cmd.strip() == "quit":
   tftp.do_quit()
   sockfd.close()
   sys.exit("Welcome")
  else:
   print("Enter the right order!!!")
   continue

if __name__ == "__main__": 
 main()