Tutorial: testing

testing

Overview

ActionHero provides test helpers so that you may try your actions and tasks within a headless environment. We do this by including a specHelper initializer which creates a server, testServer when running within the test environment. Via the testServer, you can easily call actions or tasks without making a real request.

We have chosen jest as our test framework which is included as dependencies within all new projects generated with actionhero generate. You do not need to use these testing tools, but an example will be provided which makes use of them.

You also don't need to use these test helpers, and you may want to make a real http or websocket request to test something specific. If this is the case, you can check out how ActionHero tests its own servers for examples.

Getting Started

// package.json from a new actionhero project with \`jest\`included
{
  "author"      : "YOU <[email protected]>",
  "name"        : "my_actionhero_project",
  "description" : "my actionhero project",
  "version"     : "0.1.0",
  "engines"     : {
    "node": ">=8.0.0"
  },
  "dependencies" : {
    "actionhero" : "^14.0.0",
    "ws"         : "latest"
  },
  "devDependencies" : {
    "jest" : "latest"
  },
  "scripts" : {
    "help"         : "actionhero help",
    "start"        : "actionhero start",
    "actionhero"   : "actionhero",
    "start cluster": "actionhero start cluster",
    "test"         : "jest"
  }
}

To run a jest test suite, you invoke the jest binary, ./node_modules/.bin/jest or npx jest. This will tell jest to look in your ./__tests__ folder and run any tests that it can find. There are ways to change the test folder location, only run specific tests, change the reporting format and more which you can learn about on Jest's website. We assume that you have jest installed to your project by listing it in your package.json. If you used actionHero generate to create your project, this should already be configured for you.

The majority of the time, you'll be testing actions and other methods you have written, so you'll need to "run" an actionhero server as part of your test suite. Many times you'll want to have ActionHero behave in a slightly unique way while testing (perhaps connect to a special database, don't log, etc). To do this, you can change the behavior of the config files for the test environment. Here is how we tell ActionHero not to write any logs when testing. Note the test-specific configuration overrides the defaults. Jest will automatically set NODE_ENV=test for you.

ActionHero comes with a specHelper to make it easier to test tasks and actions. This specHelper is a special server which can check things without needing to make an HTTP, websocket, etc request. If you need to check the true behavior of a server (perhaps how the router works for an HTTP request), you should make a real HTTP request in your test suite, using something like the request library (example).

Example Test

Say you had an action that was supposed to respond with a randomNumber, and you wanted to write a test for it.

const ActionHero = require('actionhero')
const actionhero = new ActionHero.Process()
let api

describe('Action', () => {
  describe('randomNumber', () => {
    beforeAll(async () => { api = await actionhero.start() })
    afterAll(async () => { await actionhero.stop() })

    let firstNumber = null

    test('generates random numbers', async () => {
      const {randomNumber} = await api.specHelper.runAction('randomNumber')
      expect(randomNumber).toBeGreaterThan(0)
      expect(randomNumber).toBeLessThan(1)
      firstNumber = randomNumber
    })

    test('is unique', async () => {
      const {randomNumber} = await api.specHelper.runAction('randomNumber')
      expect(randomNumber).toBeGreaterThan(0)
      expect(randomNumber).toBeLessThan(1)
      expect(randomNumber).not.toEqual(firstNumber)
    })
  })
})

More details on the specHelper methods can be found here

If you want to see fuller example of how to create an integration test within ActionHero, please check out the tutorial

Notes

If you do not want the specHelper actions to include metadata (data.response.serverInformation, data.response.requesterInformation, and data.response.messageId) from the server, you can configure api.specHelper.returnMetadata = false in your tests.