server side framework for dart inspired by express.js

  Framework

Queen Palace 🏰👑

Introduction

server side dart micro-framework to handle incoming http requests

hello world app

Future<void> main(List<String> args) async {
  final palace = Palace();
  palace.get('/greet_the_queen', (req, res) => res.send('Long Live The Queen 👑'));
  await palace.openGates();
}

hello world with decoration

decoration will help you split your code to parts or modules easily making the application easy to maintain

void main(List<String> args) async {
  final palace = Palace();
  palace.controllers([MainController()]);
  await palace.openGates();
}

class MainController extends PalaceController {
  MainController() : super('/');

  @Get()
  void greeTheQueen(Request req, Response res) {
    return res.send('Long Live The Queen 👑');
  }
}

Core Parts

Palace class

  • register routes and the call back for each route
  • use guards ‘palace.use(CORSGuard())’ for example
  • open the server
  • close the server

Request class

wrapper class around dart:io HttpRequest with extra functions and getters to make your life easier.

Response class

wrapper class around dart:io HttpResponse with extra functions and getters also to make the same life easier .

some of these functions are

  • res.json(data?) will convert the given data to JSON and sent it back to the user
  • res.file(path) give it path and it will give the file to the user
  • res.notFound(data?) => 404
  • res.internalServerError(data?) => 500
  • res.accepted(data?) => 200
  • res.created(data?) => 201

and so on….

Middleware aka Guard guardsman

a simple function

  • return void
  • takes any parameters you want starting from 0 parameters or the entire parameters list (see the parameters list down below)
  • guards considered as extra layer before the Handlers layers
  • they can be registered for specific route or as global guard for any kind of requests
  • they can response to incoming requests since they have access to the incoming request
  • they can preform any kind of logic before or after the handler be triggered

PalaceException class

you can throw them from any where from your application so guards can and handlers can or even the services can throw them

but what will happened then ? the palace will catch the exception format it to json including the given data object – if one was provided – and end the request life cycle

  • here some of them
  • BadRequest(data?)
  • NotFound(data?)
  • Unauthorized(data?)

Callback Parameters

if you are using the decoration you can get extra push to your endpoint callback or the guards you can extract these type of data from the incoming request

  • without decorations you can get access to the incoming request or the response by declaring the type of them
  @Get()
  void sayHi(Request req,Response Res) {
    //logic
    }

need to aces the request body directly and strong typed ? use @Body() decorator

class SignUpBody{
  late String name;
  late String email;
  late String password;
}
  @Post()
  void signUp(Request req,Response Res,@Body() SignUpBody body) {
    //logic
    }

need to access specific value from the body ?

@Body('key') String email

the same goes for

@Query()
@QueryParam()
@Param()

if you are building a guard use

@Next()

to get access to the next callback

Download server side framework to handle incoming http requests source code on GitHub