server.py

# Based on https://www.bogotobogo.com/python/python_network_programming_tcp_server_client_chat_server_chat_client_select.php

import sys
import socket
import select

HOST = ''
SOCKET_LIST = []
RECV_BUFFER = 4096
PORT = 1234

from user import User, validreg
from map import Map

def run_server():
	# set up server
	server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
	server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
	server_socket.bind((HOST, PORT))
	server_socket.listen(10)
	SOCKET_LIST.append(server_socket)

	# set up meeting hall
	mapfile=open("map.txt", "r")
	mapdata=mapfile.readlines()
	helpfile=open("help.txt", "r")
	helpdata=helpfile.readlines()
	hall = Map(mapdata, helpdata)
	hall.setup_1()

	# prepare list for users
	all_users = {}
	print("Server started on port", PORT)

	while 1:
		ready_to_read,ready_to_write,in_error = select.select(SOCKET_LIST,[],[],0)

		for sock in ready_to_read:
			# a new connection request recieved
			if sock == server_socket:
				sockfd, addr = server_socket.accept()
				SOCKET_LIST.append(sockfd)
				print("Client (%s, %s) connected" % addr)
				sockfd.send(hall.serialize())

			# a message from a client, not a new connection
			else:
				# process data recieved from client,
				try:
					# receiving data from the socket.
					dataset = sock.recv(RECV_BUFFER).decode()
					if dataset and addr in all_users:
						for data in dataset.split("$"):
							if len(data) > 0 and data[0] == 'M':
								all_users[addr].pos = int(data.split('&')[1])
								r = int(data.split('&')[2])
								i = int(data.split('&')[0][1:])

								# change room
								if r != all_users[addr].room and i == all_users[addr].index:
									all_users[addr].room = r
									print("Client @%s moved to %s" % (user.name, hall.rooms[user.room]))
								broadcast(server_socket, sock, all_users, data)
							elif len(data) > 0:
								print(data[:-1])
								broadcast(server_socket, sock, all_users, data)
					elif dataset:
						# add user
						user = User(dataset[1:].split('$')[0], hall.startPos)
						if addr in all_users.keys():
							del all_users[addr]

						if not validreg.fullmatch(user.name + "\n") or user.name in [ u.name for u in all_users.values() ] or user.name == 'SERVER':
							sockfd.send("N$".encode())
						else:
							user.socket = sockfd
							all_users[addr] = user

							if addr[0] == '127.0.0.1':
								user.op = True
								print("Promoted (%s, %s) to op" % addr)

							print("Client (%s, %s) set name to" % addr, user.name)
							for u in all_users.values():
								sockfd.send(("U" + u.serialize() + '$').encode())
							broadcast(server_socket, sockfd, all_users, "J" + user.serialize())
					else:
						# remove the socket that's broken
						if sock in SOCKET_LIST:
							SOCKET_LIST.remove(sock)

						# remove user from lists
						user = all_users[addr]
						del all_users[addr]

						print("\rClient @%s Lost connection" % user.name)
						broadcast(server_socket, None, all_users, "L" + str(user.index))

				# exception
				except:
					if addr in all_users:
						# remove user from lists
						user = all_users[addr]
						del all_users[addr]

						print("\rClient @%s Lost connection" % user.name)
						broadcast(server_socket, sock, all_users, "L" + str(user.index))
					else:
						print("\rClient (%s, %s) Lost connection" % addr)
					continue

	server_socket.close()

# broadcast chat messages to all connected clients
def broadcast (server_socket, sock, users, message):
	for user in users.values():
		socket = user.socket
		# send the message only to peer
		if user.socket != sock:
			try:
				socket.send(str.encode(message + '$'))
			except:
				# broken socket connection
				socket.close()
				# broken socket, remove it
				if socket in SOCKET_LIST:
					SOCKET_LIST.remove(socket)

if __name__ == "__main__":
	try:
		sys.exit(run_server())
	except KeyboardInterrupt:
		print('\nInterrupted')
		sys.exit(0)