A lightweight, minimal HTTP framework for productive and fun API development with dart.

This is a new project under active development

There's an express-like server framework in the dart ecosystem called Alfred.

This is the H3 implementation with similar design goals. Special thanks to Pooya Parsa and the Unjs community for making a awesome http library.

• Lightweight: H4 ships with a small core and a set of composable utilities.
• Middleware: H4 comes with built-in onRequest and onError middleware.
• Generic Handlers: Specify the return type of your handler functions.

Add H4 to your pubspec.yaml:

dependencies:
  h4: ^1.0.0

Or install with dart pub get

dart pub add h4

Import the library and start building your server:

import 'package:h4/create.dart';

void main() {
 var app = createApp();
 var router = createRouter();

 app.use(router);

 router.get("/", (event) => "Hello world!");
}

void main() {
  var app = createApp(port: 4000, autoStart: false);
  var router = createRouter();

  app.use(router);

  router.get("/hi", (event) => "Hi")

  app.start()
}

Specify the return type of your handlers

router.get<bool>("/25/**", (event) => true);

You can register global hooks:

• onRequest
• onError

These hooks are called for every request and can be used to add global logic to your app such as logging, error handling, etc.

 var app = createApp(
   port: 5173,
   onRequest: (event) => {},
   onError: (error, stacktrace, event) => {},
   afterResponse: (event) => {},
 );
 var router = createRouter();
 app.use(router);

You can throw a create error Exception that will terminate the request and send a 400 - Bad Request response

router.get('/error', (event) async {
 try {
  // Code that could fail.
 }
 catch(e) {
   throw CreateError(message: 'Womp Womp', errorCode: 400);
 }
});

The client recieves this json payload -

{
 "status": 400,
 "message": "Womp Womp"
}

You can define parameters in your routes using : prefix:

router.get('/users/:id', (event) {
 final userId = event.params['id'];
 return 'User $userId'
});

// Matches 'articles/page' and '/articles/otherPage' but not 'articles/page/otherPage'
router.get('/articles/*', (event) {
 final path = event.path;
 return 'The tea is teaing!!'
});

// Matches 'articles/foo/bar' and 'articles/rice/eba/beans'
router.get('/articles/**', (event) {
 final path = event.path;
 return 'The tea is teaing!!'
});

A set of composable utilities that help you add functionality to your server

Reads the request body as json or text depending on the contentType of the request body.

router.post("/vamos", (event) async {
 var body = await readRequestBody(event);
 return body;
});

Get the value of any of the incoming request headers. For convenience you can use the HTTPHeaders utility to get header strings.

router.post("/vamos", (event) async {
 var header = getHeader(event, HttpHeaders.userAgentHeader);
 return body;
});

A good first PR would be helping me improve the test coverage of this library, or adding one of the utilities listed here.

In the root directory run

dart test

Show respect and consideration for others when creating issues and contributing to the library. Only good vibes!