Routing

Route Parameters and Query Parameters 📝

You can define routes with dynamic parameters and query parameters to create flexible and powerful APIs. Here are some examples:

Route Parameters


void main() {
  final app = Darto();
 
  // Example route with parameters
  app.get('/user/:id', (Request req, Response res) {
    final id = req.param['id'];
 
    res.send('User ID: $id');
  });
 
  app.listen(3000);
}

Optional Parameters


void main() {
  final app = Darto();
 
  // Example optional params
  app.get('/author/:name?', (Request req, Response res) {
    final id = req.param['name'] ?? 'Unknown';
 
    res.send('User ID: $id');
  });
 
  app.listen(3000);
}

All parameters in order of definition


void main() {
  final app = Darto();
 
  // Example optional params
  app.get('/author/:name?/post/:id', (Request req, Response res) {
    // You can destructure the parameters in order of definition
    final [name, id] = req.params();
 
    // When you use optional params before required params, you must pass a default value in url
    // http://localhost:3000/author/John/post/123
    // http://localhost:3000/author/null/post/123
    res.send('Hello, $name -  $id!');
  });
 
  app.listen(3000);
}

Wildcard Parameters


void main() {
  final app = Darto();
 
  app.get('/author/*', (Request req, Response res) {
    // You can access all routes with wildcard if start with /author/
    // if necessary you can add a extra logic to check if the route is valid
    res.send('Hello World!');
  });
 
  app.listen(3000);
}

Query Parameters


void main() {
  final app = Darto();
 
  // Example route with query parameters
  // http://localhost:3000/search?name=John&age=30
  app.get('/search', (Request req, Response res) {
    final name = req.query['name'];
    final age = req.query['age'];
 
    res.send('Name: $name, Age: $age');
  });
 
  app.listen(3000);
}

Returning Implicit Responses

In Darto, you can return implicit responses directly from the route handler. Here’s an example:


void main() {
  final app = Darto();
 
  app.get('/hello', (Request req, Response res) {
    return 'Hello, World!';
  });
 
  app.listen(3000);
}

Using the Router Class

The Router class allows you to create modular route handlers. This can help you organize your routes better. Here’s an example:


import 'package:darto/darto.dart';
 
Router appRouter() {
  final router = Router();
 
  router.get('/', (req, res) {
    res.send('Dashboard Page');
  });
 
  router.get('/profile', (req, res) {
    throw Exception('Error in profile route');
  });
 
  router.get('/events/:id/attendees', (Request req, Response res) {
    return res.send('Attendees for event ${req.param['id']}');
  });
 
  return router;
}
 
void main() {
  final app = Darto();
 
  // Use the router
  app.use(appRouter());
 
  // If you want you can add a prefix in router
  app.use('/app', appRouter());
 
  app.listen(3000);
}

In this example, the appRouter function creates a new Router instance and defines several routes. The router is then used in the main application with app.use('/app', appRouter()).

Route to Redirect to an External Site


void main() {
  final app = Darto();
 
  app.get('/go', (Request req, Response res) {
    res.redirect('http://example.com');
  });
 
  app.listen(3000);
}

Route to Get the Request Body


void main() {
  final app = Darto();
 
  app.post('/file', (Request req, Response res) async {
    final body = await req.body;
 
    res.send(body);
  });
 
  app.listen(3000);
}

Routes in chained

Inspired by new version of express.js, you can chain routes. define route path, then define methods with their handlers. Syntax must be like this: router.route(path).get(handler);

Note: Type handler must be Function(Request req, Response res, Next next)


router
      .route('/new')
      .all((req, res, next) {
        req.log.debug('middleware for all methods');
        next();
      })
      .get((req, res, next) {
        res.send('New route');
      })
      .post((req, res, next) {
        next(Exception('Not implemented'));
      })
      .put((req, res, next) {
        next(Exception('Not implemented'));
      });

Routes with a function receiving the instance of the Darto class or Router class.


void routesWithDarto(Darto app) {
  app.get('/hello1', (req, res) {
    res.send('With Darto');
  });
}
 
void routesWithRouter(Router router) {
  router.get('/hello2', (req, res) {
    res.send('With Router');
  });
}
 
void main() {
  final app = Darto();
 
  app.use(routesWithDarto);
  app.use('/api', routesWithRouter);
}