Xinetd 服务调用 Python 脚本(无法正确执行)

Question

我读到了这个：

您可以使用xinetd添加一个启动python脚本的服务。标准输入和输出将通过网络在所需端口上传输，因此您不需要修改脚本(输入/raw_input和打印方法可以正常工作)。

因此，当TCP连接建立到192.168.240.37:65123时，我使用自定义的xinet服务来启动script.py。行为不符合预期。

/root/script.py

#! /usr/bin/python
my_name = raw_input("Enter your name: ")
print my_name
quit()

/etc/xinetd.d/netunique服务器

service netunique
{
disable         = no
id              = netunique-server
type            = unlisted
wait            = no
socket_type     = stream
protocol        = tcp
user            = root
server          = /usr/bin/python
server_args     = /root/script.py
port            = 65123
flags           = IPv4 REUSE
bind            = 192.168.240.37
}

systemctl状态xinetd

Nov 11 21:24:00 netunique.ourhome.com xinetd[2161]: xinetd Version 2.3.15 started with libwrap loadavg labeled-ne... in.
Nov 11 21:24:00 netunique.ourhome.com xinetd[2161]: Started working: 1 available service

telnet 192.168.240.37 65123(预期行为)

[root@netunique xinetd.d]# telnet 192.168.240.37 65123
Trying 192.168.240.37...
Connected to 192.168.240.37.
Escape character is '^]'.
Enter your name: John Smith          <-- I type name after prompt here
John Smith                           <-- Script prints entry back to screen
Connection closed by foreign host.   <-- Script does its quit()   

telnet 192.168.240.37 65123(实际行为)

[root@netunique xinetd.d]# telnet 192.168.240.37 65123
Trying 192.168.240.37...
Connected to 192.168.240.37.
Escape character is '^]'.
<blank>                              <-- no prompt as expected
John Smith                           <-- I enter some data and hit Enter
Enter your name: John Smith          <-- Hard to tell exactly what happened here
Connection closed by foreign host.   <-- Hard to tell exactly what happened here
[root@netunique xinetd.d]# 

当我说"很难说这里到底发生了什么"时，我的意思是很难说在上面的输出中，"输入您的姓名："提示后出现的"John Smith"是否是print语句的结果，也很难说"Connection closed by foreign host"是否是quit()语句的结果。

nc 192.168.240.37 65123(实际行为)

[root@netunique xinetd.d]# nc 192.168.240.37 65123
<blank>                              <-- no prompt as expected
John Smith                           <-- I enter some data and hit Enter
Enter your name: John Smith          <-- Hard to tell exactly what happened here
<-- Nothing happened here, I hit Enter
<-- I hit Enter again
Ncat: Broken pipe.                   <-- This is the end result

正如你所看到的，我和netcat的行为非常相似。

Answer 1

对我来说，真正的问题显然是我缺乏套接字编程知识。我在网上搜索"xinetd-python无数据"时发现了这篇文章(https://mail.python.org/pipermail/python-list/2007-July/423659.html)这帮助我至少让我的东西工作起来，并通过示例说明了套接字编程的实际工作方式。解决方案如下，我从原始脚本中删除了raw_input，并用帖子中的概念替换了它。

/root/script.py(原始)

#! /usr/bin/python
my_name = raw_input("Enter your name: ")
print my_name
quit()

/root/script.py(已修改并正在工作)

#! /usr/bin/python
import sys
print "Enter your name:"                
sys.stdout.flush()
my_name = sys.stdin.readline().strip()
print "Your name is %s" % my_name
sys.stdout.flush()
quit()

telnet 192.168.240.37 65123(实际行为-工作)

[root@netunique ~]# telnet 192.168.240.37 65123
Trying 192.168.240.37...
Connected to 192.168.240.37.
Escape character is '^]'.
Enter your name:
Bob Smith
Your name is Bob Smith
Connection closed by foreign host.