feat(auth) : Implemented user authentication

client/chat.go

@@ -2,8 +2,8 @@ package main
 
 import (
 	"bufio"
+	"encoding/json"
 	"fmt"
-	"log"
 	"net/url"
 	"os"
 	"strings"
@@ -24,26 +24,57 @@ func connectToEchoServer(serverURL string, username string, password string) err
 	defer c.Close()
 
 	fmt.Printf("[%s] ✓ Connected to server\n", getTimestamp())
-	err = c.WriteMessage(websocket.TextMessage, []byte(username))
+
+	// Create authentication JSON
+	authData := map[string]string{
+		"username": username,
+		"password": password,
+	}
+	authJSON, err := json.Marshal(authData)
+	if err != nil {
+		return fmt.Errorf("Failed to create authentication data: %v", err)
+	}
+
+	err = c.WriteMessage(websocket.TextMessage, authJSON)
 	if err != nil {
 		return fmt.Errorf("Failed to write to server: %v", err)
 
 	}
-	fmt.Printf("[%s] ✓ Username sent: %s\n", getTimestamp(), username)
+	fmt.Printf("[%s] ✓ Authentication data sent for user: %s\n", getTimestamp(), username)
 	fmt.Println("-------------------------------------------")
+	fmt.Println("Waiting for authentication response...")
+
+	// Wait for authentication response
+	messageType, data, err := c.ReadMessage()
+	if err != nil {
+		return fmt.Errorf("[%s] ✗ Connection error: %v", getTimestamp(), err)
+	}
+
+	if messageType == websocket.TextMessage {
+		message := string(data)
+		if strings.HasPrefix(message, "ERROR:") {
+			fmt.Printf("\r%s%s\n", "\033[K", message)
+			return fmt.Errorf("Authentication failed: %s", message)
+		} else {
+			fmt.Printf("\r%s%s\n", "\033[K", message)
+			fmt.Printf("[%s] ✓ Authentication successful!\n", getTimestamp())
+		}
+	}
+
 	fmt.Println("Listening for messages from server...")
 
 	// Run a goroutine so incoming messages are received in background while user types
 	go func() {
 		for {
 			messageType, data, err := c.ReadMessage()
 			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway, websocket.CloseAbnormalClosure) {
-				log.Printf("error: %v", err)
-				log.Println(err)
+				fmt.Printf("\r%sConnection closed by server.\n", "\033[K")
+				os.Exit(1)
 				return
 			}
 			if err != nil {
-				fmt.Printf("error: %v\n", err)
+				fmt.Printf("\r%sConnection error: %v\n", "\033[K", err)
+				os.Exit(1)
 				break
 			}
 			if messageType == websocket.TextMessage {
@@ -70,12 +101,18 @@ func connectToEchoServer(serverURL string, username string, password string) err
 
 func getUsername() string {
 	reader := bufio.NewReader(os.Stdin)
-	fmt.Print("Enter your username: ")
-	username, _ := reader.ReadString('\n')
-	if len(username) > 0 && username[len(username)-1] == '\n' {
-		username = username[:len(username)-1]
+	for {
+		fmt.Print("Enter your username: ")
+		username, _ := reader.ReadString('\n')
+		username = strings.TrimSpace(username)
+
+		if username == "" {
+			fmt.Println("Username cannot be empty. Please try again.")
+			continue
+		}
+
+		return username
 	}
-	return username
 }
 
 func getTimestamp() string {
@@ -97,7 +134,16 @@ func getServerAddress() string {
 
 func getPassword() string {
 	reader := bufio.NewReader(os.Stdin)
-	fmt.Print("Enter your password: ")
-	password, _ := reader.ReadString('\n')
-	return strings.TrimSpace(password)
+	for {
+		fmt.Print("Enter your password: ")
+		password, _ := reader.ReadString('\n')
+		password = strings.TrimSpace(password)
+
+		if password == "" {
+			fmt.Println("Password cannot be empty. Please try again.")
+			continue
+		}
+
+		return password
+	}
 }

documentation.md

@@ -71,7 +71,6 @@ getTimestamp() // returns the current timestamp as a string in the format of "02
 - Updated client/chat.go:
   - Added getServerAddress() function to capture server URL from user input via stdin.
   - Implemented default fallback to "localhost:8080" if input is empty.
-
 - Updated client/main.go:
   - Removed dependency on command-line flags for server address.
   - Reordered logic to prompt for Server Address first, then Username.
@@ -80,6 +79,7 @@ getTimestamp() // returns the current timestamp as a string in the format of "02
 ### {Krishna200608} {#108 Into Fire (Client ver.)}
 
 - Updated client/chat.go:
+
   - Added getPassword() function to capture user password from stdin.
   - Updated connectToEchoServer() signature to accept password parameter.
   - Modified message listener loop to remove "Server -> Client" prefix and redundant client-side timestamp, aligning output with the required spec.
@@ -88,3 +88,30 @@ getTimestamp() // returns the current timestamp as a string in the format of "02
   - Added call to getPassword() after username prompt.
   - Passed password to connectToEchoServer().
 - Tested locally: Verified password prompt appears and chat messages display cleanly.
+
+### {dwivediprashant} {#111 Into Fire (Server ver.)}
+
+- Updated server/server.js:
+
+  - Added bcrypt dependency for password hashing.
+  - Implemented authentication functions: hashPassword(), verifyPassword(), findUser(), createUser().
+  - Modified connection logic to handle JSON authentication data.
+  - Added proper error handling for wrong passwords and duplicate online users.
+
+- Updated server/models/User.js:
+
+  - Added password field to user schema for storing hashed passwords.
+
+- Updated server/package.json:
+
+  - Added bcrypt dependency for secure password hashing.
+
+- Updated client/chat.go:
+
+  - Added JSON encoding for authentication data.
+  - Modified connectToEchoServer() to send {"username": "...", "password": "..."}.
+  - Added input validation to prevent empty usernames and passwords.
+  - Implemented proper authentication error handling with clean exit on failure.
+  - Added success message display for correct authentication.
+
+- Tested locally: Verified new user registration, existing user login, wrong password rejection, and proper error handling.

server/.env.example

@@ -0,0 +1 @@
+MONGODB_URI=your_mongodb_uri

server/models/User.js

@@ -7,6 +7,10 @@ const userSchema = new mongoose.Schema({
     unique: true,
     trim: true,
   },
+  password: {
+    type: String,
+    required: true,
+  },
   connectedAt: {
     type: Date,
     default: Date.now,

server/package.json

@@ -11,6 +11,7 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
+    "bcrypt": "^6.0.0",
     "dotenv": "^17.2.3",
     "mongoose": "^9.1.2",
     "nodemon": "^3.1.11",