express_dt 1.0.2

A Dart library to easily create http servers and perform requests.

express_dt

A light weight library for building REST APIS easily with Dart.

The library is still a work in progress and open to contribution

Installing

Add the following to your pubspec.yaml file:

dependencies:
  express_dt: any

Usage

import 'dart:io';
import 'dart:math';

import 'package:express_dt/express_dt.dart';
import 'package:express_dt/src/model/get.dart';
import 'package:express_dt/src/wrapper/cors.dart';
import 'package:path/path.dart' as p;

dynamic main() {
  // DoSomeWork('Felix').newExpressLoggy('name');

  var express = Express();

  //let express know to serve from the /web directory
  express.use(Express.static('example/web'));

  //Allowe cross Origin requests
  express.use(Cors(['*']));

  //Use path to get directory of the files to serve on that route

  express.get(ExpressMethod(route: '/home', callbacks: [
    (ExpressRequest req, ExpressResponse res) {
      int numb = Random().nextInt(7);
      if (numb % 2 == 0) {

      } else {
        return res
            .statusCode(400)
            .toJson({"message": "Only even numbers allowed"});
      }
    },
    (
      ExpressRequest req,
      ExpressResponse res,
    ) {

      return res.statusCode(200).sendFile(p.absolute('web/index.html'));
    }
  ]));

  express.get(ExpressMethod(route: '/', callbacks: [
    (ExpressRequest req, ExpressResponse res) {
      int numb = Random().nextInt(7);
      // print(numb);
      if (numb % 2 == 0) {
      } else {
        return res
            .statusCode(400)
            .toJson({"message": "Only even numbers allowed"});
      }
    },
    (ExpressRequest req, ExpressResponse res) {
      // req.sessions!.addAll({'state': "secret"});
      return res.statusCode(200).send('<h1>Hello World</h1>');
    },
  ]));

  //route to create a jwt token
  express.get(ExpressMethod(route: '/tokenRoute', callbacks: [
    (req, res) {
      String token = expressSign('Sjkbdjaksdjas', env['EXPRESS_SECRET_KEY']!);
      return res.statusCode(200).toJson({"token": token});
    }
  ]));


  //route with a middleware to verify jwt token
  express.get(ExpressMethod(route: '/verifyToken', callbacks: [
    (req, res) {
      String? token = extractTokenFromHeader(req.headers);
      if (token == null) {
        return res.statusCode(400).send('Authorization Failed');
      } else {
        var data = expressVerify(token, env['EXPRESS_SECRET_KEY']!);
        if (data == null) {
          return res.statusCode(400).send('Authorization Failed');
        }
      }
    },
    (req, res) {
      return res.statusCode(200).send('Authorized');
    }
  ]));
  
  //post request

  express.post(ExpressMethod(route: '/post', callbacks: [
    (ExpressRequest req, ExpressResponse res) async {
      return res.statusCode(200).toJson(req.body);
    }
  ]));

  //plain text

  express.get(ExpressMethod(route: '/text', callbacks: [
    (ExpressRequest req, ExpressResponse res) {
      return res.statusCode(200).send('data');
    }
  ]));

  // request parameters

  express.get(ExpressMethod(route: '/param/:username', callbacks: [
    (ExpressRequest req, ExpressResponse res) {
      return res.statusCode(200).toJson({'params': req.params});
    }
  ]));

  // query parameters
  express.get(ExpressMethod(route: '/query', callbacks: [
    (ExpressRequest req, ExpressResponse res) {
      return res.statusCode(200).toJson(req.query);
    }
  ]));

  //Upload Files

  express.post(ExpressMethod(route: 'upload', callbacks: [
    (req, res) async {
      for (var i = 0; i < req.files.keys.length; i++) {
        //Handle your file stream as you see fit, write to file, pipe to a cdn etc --->
        var file = File(req.files[req.files.keys.toList()[i]]!.filename!);
        await for (var data in req
            .files[req.files.keys.toList()[i]]!.streamController!.stream) {
          if (data is String) {
            await file.writeAsString(data, mode: FileMode.append);
          } else {
            await file.writeAsBytes(data, mode: FileMode.append);
          }
        }
      }

      return res.statusCode(200).toJson(req.body);
    }
  ]));

  //Bind server to port 4000
  express.stream(4000, callback: () {});
}

Make Requests

• Use the ExpressMethod to make a request.
• It takes in a route parameter and a list of callback functions.
• The function can be just one, or you can have a middleware and your callback functinon.
• The callback function takes ExpressRequest and ExpressResponse as parameters

Other available request types:

• PUT
• PATCH
• DELETE
• COPY
• HEAD
• OPTIONS
• LINK
• UNLINK
• PURGE
• LOCK
• UNLOCK
• PROFIND
• VIEW

Secure routes

//route to create a jwt token
  express.get(ExpressMethod(route: '/tokenRoute', callbacks: [
    (req, res) {

      //Use expressSign() to create a token with the id and your secret key
      String token = expressSign('Sjkbdjaksdjas', env['EXPRESS_SECRET_KEY']!);
      return res.statusCode(200).toJson({"token": token});
    }
  ]));


  //route with a middleware to verify jwt token
  express.get(ExpressMethod(route: '/verifyToken', callbacks: [
    (req, res) {
      //Extract token from header
      String? token = extractTokenFromHeader(req.headers);
      if (token == null) {
        return res.statusCode(400).send('Authorization Failed');
      } else {
        //Verify the token
        var data = expressVerify(token, env['EXPRESS_SECRET_KEY']!);
        if (data == null) {
          return res.statusCode(400).send('Authorization Failed');
        }
      }
    },
    //proceed to the request
    (req, res) {
      return res.statusCode(200).send('Authorized');
    }
  ]));

Working with html files

//let express know to serve from the /web directory
  express.use(Express.static('example/web'));

  express.get(ExpressMethod(route: '/home', callbacks: [

    (
      ExpressRequest req,
      ExpressResponse res,
    ) {

      return res.statusCode(200).sendFile(p.absolute('web/index.html'));
    }
  ]));