koa-tiny-router

koa-tiny-router

koa-tiny-router is a very simple router package for Koa2. It uses the same underlying library for parsing routes as koa-router, but it has one fundamental difference from koa-router: it doesn't use the HTTP method for matching routes.

This library can work in conjuction with koa-router though, so you can have parts of your application use koa-router, and other parts use koa-tiny-router depending on your needs.

API-documentation

• koa-tiny-router
  • Router ⏏
    • new Router()
    • instance
      • .match ⇒ Router

koa-tiny-router

kind: package

Router

kind: Exported class

new Router()

Create a new router.

Example

Basic usage:

var app = require('koa')();
var router = require('koa-source-router')();
router.match('/foo', function(ctx, next) {...});

router.match ⇒ Router

Match a path and execute a middleware function if it does. The path is evaluated using path-to-regexp.

Example

router.match('/article/:id', function(ctx, next) {
  ctx.body = 'Hello world' + ctx.params.id;
});

Query strings will not be considered when matching. Any URL parameters (such as :id) in the last example will be set to ctx.params.

Use-case

This library was developed at Turnstyle, because while we developing a REST webservice, we noticed that:

1. There was a lot of repetition in our routes.
2. It was annoying to write per-route middleware.

In our use-case, we wanted to express the following pattern efficiently.

Controller class

We have one ES2015 class per route or resource. These are our controllers. We never break this pattern. This allows our 'controller' to look like this:

class FooController {

  async get() {

  }

  async put() {

  }

  async del() {

  }

  async post() {

  }

  async options() {

  }

}

If there's a route that only supports 1 method (GET for example), that means that those controllers also have one method (async get()).

We use a super-class that implements defaults for all these methods, which just cause a 405 Method Not Allowed to be returned.

The superclass looks a bit like this:

class BaseController {

  async match(ctx) {

    // Do content-negotiation.
    // Do validation.
    // Do pre-condition checking.
    // Call this[ctx.method](ctx).

  }

  async get(ctx) {

    // Throw 405

  }

  async put() {

    // Throw 405

  }

  async del() {

    // Throw 405

  }

  async post() {

    // Throw 405

  }

  async options() {

    // Add a bunch of default headers

  }

}

Having a a default 'match' method that matches every HTTP request is super use-ful, as we can do a number of things that are applicable to each HTTP request, but the default koa-router does not elegantly handle this.

Running tests

Run tests using npm test.