shelf_router library Null safety

A request routing library for shelf.

When writing a shelf web server it is often desirable to route requests to different handlers based on HTTP method and path patterns. The following example demonstrates how to do this using Router.

Example

import 'package:shelf_router/shelf_router.dart';
import 'package:shelf/shelf.dart' show Request, Response;
import 'package:shelf/shelf_io.dart' as io;

void main() async {
  // Create a router
  final router = Router();

  // Handle GET requests with a path matching ^/say-hello/[^\]*$
  router.get('/say-hello/<name>', (Request request, String name) async {
    return Response.ok('hello $name');
  });

  // Listen for requests on port localhost:8080
  await io.serve(router.handler, 'localhost', 8080);
}

As it is often useful to organize request handlers in classes, methods can be annotated with the Route annotation, allowing the shelf_router_generator package to generated a method for creating a Router wrapping the class.

To automatically generate add the shelf_router_generator and build_runner packages to dev_dependencies. The follow the example below and generate code using pub run build_runner build.

Example, assume file name is hello.dart.

import 'package:shelf_router/shelf_router.dart';
import 'package:shelf/shelf.dart' show Request, Response;
import 'package:shelf/shelf_io.dart' as io;

// include the generated part, assumes current file is 'hello.dart'.
part 'hello.g.dart';

class HelloService {
  // Annotate a handler with the `Route` annotation.
  @Route.get('/say-hello/<name>')
  Future<Response> _sayHello(Request request, String name) async {
    return Response.ok('hello $name');
  }

  // Use the generated function `_$<ClassName>Router(<ClassName> instance)`
  // to create a getter returning a `Router` for this instance of
  // `HelloService`
  Router get router => _$HelloServiceRouter(this);
}

void main() async {
  // Create a `HelloService` instance
  final service = HelloService();

  await io.serve(service.router.handler, 'localhost', 8080);
}

Classes

Route
Annotation for handler methods that requests should be routed when using package shelf_router_generator. [...]
Router
A shelf Router routes requests to handlers based on HTTP verb and route pattern. [...]

Functions

params(Request request, String name) String
Get a URL parameter captured by the Router.