从对象列表中返回属性列表

Question

I'm developing a simple TCP chat application server-client to learn Python and I'm not sure about data structures to use.

Server side I've defined client class and its attributes: socket, username, room and online_status. Every client is added to clients list and also, at the same time, its socket is added to connections list. Server runs in an always-true loop listening for incoming messages using the following declaration

(ready_to_read, _, _) = select.select([server_socket] + list(connections), [], [])

Is there any way to list every socket of every client objects and do like

(ready_to_read, _, _) = select.select( list(client.socket), [], [])

Answer 1

Unsure that I have really understood what you want, but assuming that you want to build a list of sockets from the list of client instances, you can use a list comprehension:

(ready_to_read, _, _) = select.select( [client.socket for client in clients], [], [])

(assuming clients is a list of the client instances)