telnet连接Python套接字服务器时遇到问题

Question

我最近开始做一个物联网项目，遇到的第一个问题就是搭建一个基本的服务器有点困难。按照这个指南进行一些初步测试，这里是我用的代码：

'''


   Simple socket server using threads
'''

import socket
import sys

HOST = ''   # Symbolic name, meaning all available interfaces
PORT = 8888 # Arbitrary non-privileged port

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print 'Socket created'

#Bind socket to local host and port
try:
    s.bind((HOST, PORT))
except socket.error as msg:
    print 'Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + msg[1]
    sys.exit()

print 'Socket bind complete'

#Start listening on socket
s.listen(10)
print 'Socket now listening'

#now keep talking with the client
while 1:
    #wait to accept a connection - blocking call
    conn, addr = s.accept()
    print 'Connected with ' + addr[0] + ':' + str(addr[1])

s.close()

我可以成功搭建服务器，它会在一个端口上监听，但当我尝试用telnet连接时，总是超时。因为我在大学的网络上，这可能是导致连接不上的原因吗？我记得之前在C语言中做过类似的事情，那时候似乎是可以的……

Answer 1

这段代码能正常运行，但它没有和客户端进行数据的发送和接收。下面这个小改动可以让服务器向任何幸运的客户端发送 beer tasty。

源代码

'''
Simple socket server using threads
'''

import socket
import sys

HOST = ''   # Symbolic name, meaning all available interfaces
PORT = 8888 # Arbitrary non-privileged port

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print 'Socket created'

#Bind socket to local host and port
try:
    s.bind((HOST, PORT))
except socket.error as msg:
    print 'Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + msg[1]
    sys.exit()

print 'Socket bind complete'

#Start listening on socket
s.listen(10)
print 'Socket now listening'

#now keep talking with the client
while 1:
    #wait to accept a connection - blocking call
    conn, addr = s.accept()
    print 'Connected with ' + addr[0] + ':' + str(addr[1])
    conn.send('beer tasty\n')   # <==
    conn.close()
s.close()

在Linux中用Netcat进行测试。（Telnet也应该可以用）

测试

$ echo beer | nc -q1 localhost 8888
Connected with 127.0.0.1:37484
beer tasty