synth

Simple, minimal, and efficient Dart web developement framework.

Prerequisite: Dart and Git installed in your machine.

Basic usage

Step 1: Create a project using Dart IDE or commandline. Instructions below is thru commandline.

$ mkdir hello
$ cd hello

Step 2: Inside hello directory create a pubspec.yaml file with the contents below.

name: hello
dependencies:
  synth:
    git: git://github.com/maiah/synth.git

Step 3: Inside hello directory execute pub install. This will create packages folder and download the synth library.

$ pub install

Step 4: Create hello_server.dart file inside hello folder and import synth.dart library in that file.

import 'package:synth/synth.dart';

Step 5: And also in this file create main method and define your routes and start the HTTP server.

main () {
  route('GET', '/', (req, res)
    => res.write('Hello, World!'));

  start(port: 7000);
  print('Listening on port 7000');
}

Step 6: Run your Dart program using Dart IDE or commandline. Instructions below is thru commandline.

$ dart hello_server.dart

Step 7: Open your web browser and go to http://localhost:7000 and the message below will be shown.

Hello, World!

Routing

You can register a route with a path that holds a variable like below.

route('GET', '/person/:name', (req, res)
  => res.write('Hi there.'));

Then you can access this route with http://localhost:7000/person/maiah URL.

You can also have multiple variable in a single route path.

route('GET', '/person/:name/department/:id', (req, res)
  => res.write('Hello there.'));

Then you can access this route with http://localhost:7000/person/maiah/department/557 URL.

Adding middleware

Adding middleware is very simple. It's like providing a HTTP request handler. But you have to register your middleware thru the use method.

Unlike request handler, middlewares has a 3rd parameter next that can be executed to call the next middleware in the stack. Take a look at the typedef Middleware signature below:

typedef void Middleware(Request req, Response res, next);

For example you want to add a middleware that will log the request path each time a request is processed.

use((req, res, next) {
  print('Request path is ${req.path}');
  next(); // Executes the next middleware in the stack if any.
});

The code above will register the middleware closure you created and will execute everytime a request is processed.

Adding middleware into a specific route

Adding middleware into a specific route is done thru route method. The middleware method signature is the same. Add it before the request handler like below.

...
var someMiddleware = (req, res, next) {
  print('Some middleware here.');
  next();
}
...

route('GET', '/', someMiddleware, (req, res) {
  res.write('A route with middleware.');
});

The code above will register and execute the middleware only for this specific route.

Built-in middlewares

• logPath - Used for logging the request path and its query parameters.
• reqContent - Used to gather request POST data and populate Request#dataMap property which can be accessed by user-defined request handlers and other middlewares.
• reqJsonContent - Similar to reqContent, except it parses JSON POST data and populates Request#dataObj.

Synth Robot Boy art by KabisCube kabiscube@yahoo.com