added comments

server.py

@@ -313,6 +313,7 @@ class Server(multiprocessing.Process):
             # ascii value before A
             return 64
 
+    # listen for servers if they want to join the DS
     def listen_for_servers(self):
 
         BROADCAST_PORT = 49154
@@ -437,6 +438,7 @@ class Server(multiprocessing.Process):
             client_cache_key = group + str(self.client_cache_key_offset)
             self.local_clients_cache[client_cache_key] = client_addr
 
+    # find address of groupchat server to inform client
     def find_groupchat_server_addresse(self, group):
         # double check if group really exist
         for key in self.local_group_cache:
@@ -490,7 +492,9 @@ class Server(multiprocessing.Process):
         #new_server.send_reply_to_client()
 
         return self.server_port
+    
 
+    # send updated group view/servers cache to all server
     def updateCacheList(self):
         PORT = 5980
         BROADCAST_ADDRESS = self.get_broadcast_address()
@@ -513,6 +517,7 @@ class Server(multiprocessing.Process):
             broadcast_socket.sendto(MSG, (BROADCAST_ADDRESS, PORT))
         broadcast_socket.close()
 
+    # listen for update of the groupview/server cache by MAIN server
     def listen_for_cache_update(self):
         BROADCAST_ADDRESS = self.get_broadcast_address()
         BROADCAST_PORT = 5980
@@ -555,6 +560,7 @@ class Server(multiprocessing.Process):
             except socket.timeout:
                 pass #Timeout reached
 
+    # listen for client chat messages to distribute them to all group members afterwards
     def listen_for_client_messages(self):
 
         PORT = 50001
@@ -580,6 +586,7 @@ class Server(multiprocessing.Process):
             if message:
                 self.distribute_chat_message(message, addr)
 
+    # determine the receiver list of the received client chat message
     def distribute_chat_message(self, message, addr):
         group = self.find_group_of_client(addr)
 
@@ -594,6 +601,7 @@ class Server(multiprocessing.Process):
         distribute_chat_thread = threading.Thread(target=self.send_chat_message_to_clients(message, receiver_list))
         distribute_chat_thread.start()
 
+    # distribute the received client chat message to all members of the group
     def send_chat_message_to_clients(self, message, receiver_list):
 
         PORT = 51000