server.py

import socket  
import threading 

host = '127.0.0.1' 

port = 55555  

# to start server
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server.bind((host, port)) 
server.listen() 

clients = [] 
nicknames = [] 

def broadcast_msg(message):  
    for client in clients:
        client.send(message)  


def manage(client): 
    while True: 
        try: 
            message = client.recv(1024).decode('ascii')
            if message.startswith('KICK'):
                if nicknames[clients.index(client)]=='admin' :
                    name_to_kick=message[5:]
                    kick_user(name_to_kick)
                else:
                    client.send('Command was refused!'.encode('ascii'))
            elif message.startswith('BAN'):
                if nicknames[clients.index(client)] == 'admin' :
                    name_to_ban=message[4:]
                    kick_user(name_to_ban)
                    with open('bans.txt','a') as f:
                        f.write(f'{name_to_ban}\n')
                    print(f'{name_to_ban} was banned from the server')
                else:
                    client.send('Command was refused!'.encode('ascii'))
            else:
                message2=message.encode('ascii')
                broadcast_msg(message2)
        except:  # on exception
            if client in clients:
                index = clients.index(client)
                clients.remove(client)
                client.close()
                nickname = nicknames[index]
                broadcast_msg(
                    f'{nickname} has left the chat.'.encode('ascii'))
                print("Client has left the chat with nickname ", nickname)
                nicknames.remove(nickname)
                break


def receive():
    while True: 
        client, address = server.accept()  
        print(f'New Client is connected with the Address = {str(address)}')
        client.send('NICK'.encode('ascii'))  
        nickname = client.recv(1024).decode('ascii')
        with open('bans.txt','r') as f:
            bans=f.readlines()
        if nickname+'\n' in bans:
            client.send('BAN'.encode('ascii'))
            client.close()
            continue
        if nickname =='admin' :
            client.send('pass'.encode('ascii'))
            password=client.recv(1024).decode('ascii')
            if password != 'adminpass':
                client.send('Incorrect'.encode('ascii'))
                client.close()
                continue
        nicknames.append(nickname)
        clients.append(client)
        print(f'Client\'s nickname : {nickname}')
        broadcast_msg(f'{nickname} has just joined the chat !'.encode('ascii'))
        client.send(f'Successfully Connected to Server '.encode('ascii'))
        thread = threading.Thread(target=manage, args=(client,))
        thread.start()
def kick_user(name):
    if name in nicknames:
        name_index=nicknames.index(name)
        client_to_kick=clients[name_index]
        clients.remove(client_to_kick)
        client_to_kick.send('You were kicked  '.encode('ascii'))
        client_to_kick.close()
        nicknames.remove(name)
        broadcast_msg(f'{name} was kicked by an admin'.encode('ascii'))


print("-----------------------------server is running-------------------------")
receive()