chrsalx/koa-test

Testing framework for koa apps built using tape-async and supertest.

koa-test

Easy to use framework for koa API testing built on tape-async and supertest. The purpose of this project is to make testing for APIs as descriptive as possible.

Installation

npm i -D koa-test

Usage

Set up an scenario that will only pass only when all your assertions pass.

Simple API Testing

const createTestSuite = require('koa-test');
const koa = require('koa');

function apiFactory() {
  return koa()
    .use(function* helloWorld(next) {
      this.body = 'Hello World!';
      yield next;
    });
}

const createScenario = createTestSuite(apiFactory);

createScenario(
  {
    title: 'GET /',
    path: '/',
    method: 'get',
    assertions: [
      (res, t) => t.equal(res.status, 200),
      (res, t) => t.equal(res.text, 'Hello World!');
    ],
  },
);

You can also take advantage of dependency injection in order to easily unit test your API (or pass the real thing and do some integration testing if you are into that).

const createTestSuite = require('koa-test');
const koa = require('koa');

function apiFactory(dependencies) {
  const { returnHelloWorld } = dependencies;

  return koa()
    .use(function* helloWorld(next) {
      this.body = returnHelloWorld();
      yield next;
    });
}

const createScenario = createTestSuite(apiFactory);

createScenario(
  {
    title: 'GET /',
    path: '/',
    method: 'get',
    assertions: [
      (res, t) => t.equal(res.status, 200),
      (res, t) => t.equal(res.text, 'Hello World from a dependency!');
    ],
  },
  {
    returnHelloWorld: () => 'Hello World from a dependency!';
  }
);

API

createTestSuite

createTestSuite takes in a function that returns a koa app and returns a createScenario function that allows you to build your testing scenarios.

function apiFactory() {
  return koa()
    .use(function* helloWorld(next) {
      this.body = 'Hello World!';
      yield next;
    });
}

const createScenario = createTestSuite(apiFactory);

createScenario

createScenario takes two objects: config which is the setup for the request you will send to your API and dependencies which is an optional parameter containing all the dependencies you want to pass to your factory.

createScenario(
  {
    title: 'GET /',
    path: '/',
    method: 'get',
    assertions: [
      (res, t) => t.equal(res.status, 200),
      (res, t) => t.equal(res.text, 'Hello World from a dependency!');
    ],
  },
  {
    returnHelloWorld: () => 'Hello World from a dependency!';
  }
);

config

The config object has several fields that are used to build your request to your API.

• title: The title that you will see int the TAP output on tape.
• path: The path that your request will write to. (required)
• method: The method which will be used on the request. (required)
• body: The payload of the request.
• query: Object containing the query parameters of the request.
• headers: Object containing all the headers of the request.
• assertions: Array of functions that will receive tape's test object and the response object retreived from request.

assertion

An assertion function is callback that accepts two parameters: res which is the whole response object returned by supertest and t which is the whole assertion object created by tape.

(res, t) => t.equals(res.status, 200);

dependencies

The dependencies object is optional and it only serves the purpose to provide dependency injection to your API.