JWT Module

JWT_SECRET=your_secret_key_here
JWT_EXPIRY=3600

let payload = {
    "user_id": 123,
    "username": "alice",
    "email": "alice@example.com"
};
 
let token = jwt.sign(payload);
print(token);  // eyJhbGciOiJIUzI1NiIsInR5cCI6...

let token = jwt.sign({"user_id": 123});
let is_valid = jwt.verify(token);
print(is_valid);  // true

let payload = {"user_id": 123, "role": "admin"};
let token = jwt.sign(payload);
 
let decoded = jwt.decode(token);
print(decoded["user_id"]);  // 123
print(decoded["role"]);     // "admin"

// Login endpoint
func handle_login(req, res) {
    let credentials = json.parse(req.body);
    let username = credentials["username"];
    let password = credentials["password"];
    
    // Authenticate user
    let db = sqlite.open("users.db");
    let sql = "SELECT id, password_hash FROM users WHERE username = '" + username + "'";
    let results = sqlite.query(db, sql);
    
    if (len(results) == 0) {
        res.writeHead(401, {"Content-Type": "application/json"});
        res.end(json.stringify({"error": "Invalid credentials"}));
        return;
    }
    
    let user = results[0];
    if (!auth.verify(password, user["password_hash"])) {
        res.writeHead(401, {"Content-Type": "application/json"});
        res.end(json.stringify({"error": "Invalid credentials"}));
        return;
    }
    
    // Create JWT
    let token = jwt.sign({
        "user_id": user["id"],
        "username": username
    });
    
    res.writeHead(200, {"Content-Type": "application/json"});
    res.end(json.stringify({"token": token}));
    
    sqlite.close(db);
}

func verify_token(token_string) {
    if (token_string == null) {
        return null;
    }
    
    if (!jwt.verify(token_string)) {
        return null;
    }
    
    return jwt.decode(token_string);
}
 
func handle_protected_route(req, res) {
    // Get token from header
    let auth_header = req.headers["Authorization"];
    if (auth_header == null) {
        res.writeHead(401, {"Content-Type": "application/json"});
        res.end(json.stringify({"error": "No token provided"}));
        return;
    }
    
    // Verify token
    let token = replace(auth_header, "Bearer ", "");
    let user_data = verify_token(token);
    
    if (user_data == null) {
        res.writeHead(401, {"Content-Type": "application/json"});
        res.end(json.stringify({"error": "Invalid token"}));
        return;
    }
    
    // User is authenticated
    res.writeHead(200, {"Content-Type": "application/json"});
    res.end(json.stringify({
        "message": "Welcome",
        "user_id": user_data["user_id"]
    }));
}

let active_sessions = {};
 
func create_session(user_id, username) {
    let token = jwt.sign({
        "user_id": user_id,
        "username": username
    });
    
    active_sessions[token] = {
        "user_id": user_id,
        "created_at": "2024-12-12",
        "last_activity": "2024-12-12"
    };
    
    return token;
}
 
func invalidate_session(token) {
    if (token in active_sessions) {
        // Remove from active sessions
        delete active_sessions[token];
        return true;
    }
    return false;
}