Fix leave and exit

Author: BinniesLite

GUI/src/main/java/org/example/client.java

@@ -28,11 +28,7 @@ public static void main(String argv[]) {
             client newClient = new client();
             newClient.connect();
             newClient.init();
-            //newClient.clientGUI = new GUI();
-            //newClient.clientGUI.init();
-            //newClient.close();
-        }
-        catch (Exception e) {
+        } catch (Exception e) {
             System.out.println("Exception occurred in client main:" + e);
         }
     }
@@ -54,34 +50,32 @@ public void init() {
         }
     }
 
-    public void close() {
-        try {
-            controlSocket.close();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
-        sendMsgThread.interrupt();
-        rcvMsgThread.interrupt();
-    }
-
     /* Connect to the server */
-    public void connect() {
-        try {
-            // establish the control socket
-            controlSocket = new Socket("localhost", 6789);
-
-            // get references to the socket input and output streams
-            InputStreamReader isr = new InputStreamReader(controlSocket.getInputStream());
-            controlReader = new BufferedReader(isr);
-            controlWriter = new DataOutputStream(controlSocket.getOutputStream());
-        } 
-        catch (UnknownHostException ex) {
-            System.out.println("UnknownHostException during connection attempt: " + ex);
-        } 
-        catch (IOException ex) {
-            System.out.println("IOException during connection attempt: " + ex);
-        }
-    } /* end client.connect() */
+public void connect() {
+    try {
+        controlSocket = new Socket("localhost", 6789);
+        controlReader = new BufferedReader(new InputStreamReader(controlSocket.getInputStream()));
+        controlWriter = new DataOutputStream(controlSocket.getOutputStream());
+    } catch (UnknownHostException ex) {
+        System.out.println("UnknownHostException during connection attempt: " + ex);
+        close();
+    } catch (IOException ex) {
+        System.out.println("IOException during connection attempt: " + ex);
+        close();
+    }
+}
+
+public void close() {
+    try {
+        if (controlSocket != null) controlSocket.close();
+        if (controlReader != null) controlReader.close();
+        if (controlWriter != null) controlWriter.close();
+    } catch (IOException e) {
+        System.err.println("Error closing resources: " + e.getMessage());
+    }
+    if (sendMsgThread != null) sendMsgThread.interrupt();
+    if (rcvMsgThread != null) rcvMsgThread.interrupt();
+}
 
     final class TcpSend implements Runnable {
         Socket socket;  // reference to connection socket
@@ -116,6 +110,10 @@ public void sendMsg() {
                         System.out.println("exiting client program");
                         break;
                     }
+                    response = controlReader.readLine();
+                     if (response != null) {
+                   System.out.println(response);
+                }
                 }
                 catch (IOException ex) {
                     System.out.println("IOException occured during send message attempt: " + ex);

client.py

@@ -2,42 +2,57 @@
 import threading
 
 def receive_messages():
-    while True:
+    global running
+    while running:
         try:
             message = client.recv(1024).decode('utf-8')
+            if message.startswith("exit"):
+                running = False
+                break
+                
             print(message)
-        except:
-            print('An error occurred!')
-            client.close()
+        except Exception as e:
+            print(f'An error occurred: {e}')
             break
 
 def send_messages():
-    while True:
+    global running
+    
+    while running:
         try:
             command = input()
-            
-            # Send commands to the server
             client.send(command.encode('utf-8'))
-            msg = client.recv(1024).decode('utf-8')
-            if msg[0] == "exit":
-                print("Exiting the group chat")
-                client.close()
-                break
-        except:
-            print('Exiting the group chat')
-            client.close()
+        except Exception as e:
+            print(f'Exiting the group chat {e}')
             break
 
 if __name__ == "__main__":
-    host = 'localhost'
-    port = 6789
+    running = True
+    s = ""
+    while True:
+        s = input("%connect [address] [port]: To connect to the server\n")
+        
+        if not s.startswith("%connect"):
+            print("invalid inputs")
+            continue
+        else:
+            break 
+    
+    s = s.split(" ")
+    host, port = s[1], int(s[2])
     client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
     client.connect((host, port))
 
     # Start receiving messages in a separate thread
     receive_thread = threading.Thread(target=receive_messages)
     receive_thread.start()
 
-    # Start sending messages (commands) in the main thread
+    # Start sending messages in a separate thread
     send_thread = threading.Thread(target=send_messages)
     send_thread.start()
+
+    # Join threads to ensure proper exit
+    receive_thread.join()
+    send_thread.join()
+
+    client.close()

server.py

@@ -1,6 +1,10 @@
 import socket
 import threading
 import time
+import signal
+
+# Flag to control server loop
+running = True
 
 def broadcast(message):
     for client in clients:
@@ -11,7 +15,8 @@ def broadcast_group(message, group_id):
         client.send(message)
 
 def handle_client(client):
-    while True:
+    global running
+    while running:
         try:
             message = client.recv(1024).decode('utf-8')
             if message:
@@ -60,6 +65,7 @@ def handle_client(client):
                     client.send('Invalid command format. Use "%connect [address] [port]\n".'.encode('utf-8'))
 
             elif command == "%post":
+                
                 subject = message[1]
                 content = " ".join(message[2:])
 
@@ -78,12 +84,14 @@ def handle_client(client):
                 client.send(f"Users in the group:\n{user_list}\n".encode('utf-8'))
 
             elif command == '%leave':
-                username = usernames[client]
-                del usernames[client]
+                if client in usernames:
+                    username = usernames[client]
+                    
+                    broadcast(f'{username} has left the chat room!\n'.encode('utf-8'))
+                    del usernames[client]
                 clients.remove(client)
-                broadcast(f'{username} has left the chat room!\n'.encode('utf-8'))
                 client.send("You left the chat room!\n".encode('utf-8'))
-                client.close()
+                
             elif command == '%message':
                 msg_id = int(message[1])
 
@@ -102,11 +110,12 @@ def handle_client(client):
                 client.send("You are disconnected from the server!\n".encode('utf-8'))
                 client.send("exit".encode("utf-8"))
                 client.close()
+                break
             elif command == "%groups":
                 response = f"Here're all the group available: \n {' '.join([str(i) for i in range(GROUPS)])}" 
 
                 client.send(response.encode("utf-8"))
-            elif command == "%groupjoin":
+            elif command == "%groupsjoin":
                 if len(message) < 2:
                     client.send('Invalid command format. Try again!\n'.encode('utf-8'))
                     continue
@@ -126,7 +135,6 @@ def handle_client(client):
                 if client in usernames:
                     username = usernames[client]
 
-                
                 client.send(f"User {username} join group {group_id}".encode("utf-8"))
             elif command == "%groupusers":
                 if len(message) < 2:
@@ -211,14 +219,54 @@ def handle_client(client):
             # print(e)
             print("Exception occurred in server: " + e)
             break
-        
+
+# Function to handle SIGINT
+def signal_handler(sig, frame):
+    global running
+    print("\nServer is shutting down...")
+    running = False
+    server.close()
+    for client in clients:
+        client.close()
+    print("Server shutdown complete.")
+
 def run_server():
+    global running
     print("Server started. Waiting for connections...")
-    while True:
-        client, address = server.accept()        
-        clients.append(client)
-        print(f'Connection established with {address}')
-        client.send("""Welcome to the chat room!
+    while running:
+        try:
+            client, address = server.accept()
+            clients.append(client)
+            print(f'Connection established with {address}')
+            client.send(welcome_message.encode('utf-8'))
+            thread = threading.Thread(target=handle_client, args=(client,))
+            thread.start()
+        except OSError:
+            # This exception will be raised when the server socket is closed
+            break
+
+if __name__ == "__main__":
+    host = 'localhost'
+    port = 6789
+    GROUPS = 5
+    
+    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    server.bind((host, port))
+    server.listen()
+    
+    clients = []  # List to keep track of clients
+    usernames = {}  # client -> username
+    messages = []  # messages
+    group_messages = {}  # group -> messages
+    group_users = {}  # group -> client
+
+    for i in range(GROUPS): 
+        group_users[i] = []
+        group_messages[i] = []
+
+    # Define welcome message outside the loop
+    welcome_message = """
+        Welcome to the chat room!
         Available commands:
         %connect [address] [port]: Connect to a different server
         %join [username]: Join with the username
@@ -235,29 +283,14 @@ def run_server():
         %groupusers [group ID]: Retrieve a list of users in the given group
         %groupmessage [group ID] [message ID]: retrieve the content of an earlier post if you belong to that group
         %groupleave [group ID]: Leave the current group if client is in that group
-        """.encode('utf-8'))
+        """
 
-        thread = threading.Thread(target=handle_client, args=(client,))
-        thread.start()
+    # Register the signal handler
+    signal.signal(signal.SIGINT, signal_handler)
 
-if __name__ == "__main__":    
-    host = 'localhost'
-    port = 6789
-    GROUPS = 5
-    
-    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-    server.bind((host, port))
-    server.listen()
-    
-    
-    clients: list[type(socket)] = []
-    usernames = {} # client -> username
-    messages = [] # messages
-    group_messages = {} # group -> messages
-    group_users = {} # group -> client
-    
-    for i in range(GROUPS): 
-        group_users[i] = []
-        group_messages[i] = []
-    
     run_server()
+
+
+
+
+