psutil.net_connections() should return namedtuple, but it is not behaving as one

Question

I'm trying to find out if my server (should be running on 127.0.0.1:5000) is actually running. I'm trying to use psutil.net_connections() to figure it out:

filter(lambda conn: conn.raddr.ip == '127.0.0.1' and conn.raddr.port == 5000, psutil.net_connections())

This should give me the item corresponds to my server, and to check if I actually got something, I just check the len(tuple(...))). However, using the tuple(...) gives me AttributeError: 'tuple' object has no attribute 'ip' which I don't get, since the inner tuple (i.e. conn.raddr does have an "ip" attr).

This happens also when looping regularly:

In [22]: for conn in psutil.net_connections():
    ...:     if conn.raddr.ip == '127.0.0.1' and conn.raddr.port == 5000:
    ...:         break
    ...: else:
    ...:     print('server is down')

BUT when using it like this, it works!

In [23]: a=psutil.net_connections()[0]
In [24]: a.raddr.ip
Out[24]: '35.190.242.205'

psutil version: 5.7.2

Answer 1

Not all raddr have an ip attribute. The documentation says:

raddr: the remote address as a (ip, port) named tuple or an absolute path in case of UNIX sockets. When the remote endpoint is not connected you’ll get an empty tuple (AF_INET*) or "" (AF_UNIX). For UNIX sockets see notes below.

So you should check that raddr not empty before trying to access the ip and port attributes.

filter(lambda conn: conn.raddr and conn.raddr.ip == '127.0.0.1' and conn.raddr.port == 5000, psutil.net_connections())