Nightmare Gremlins

Gremlin.js actions for Nightmare.js to allow for monkey testing

Introduction

Nightmare Gremlins is an action and collection of tasks for Nightmare.js that allows for monkey testing via the Electron app.

There are two ways to use this npm:

1. Singular action that extends the Nightmare prototype via Nightmare.action

2. Series of individual tasks to be consumed by a Nightmare instance via nightmare.use.

Singular Action

The Nightmare prototype can be extended by using the Nightmare.action method:

import Nightmare from 'nightmare';
import gremlins from 'nightmare-gremlins';

Nightmare.action('gremlins', gremlins);
const nightmare = Nightmare();

const gremlinOptions = {
  seed: Date.now(),
  unleash: {
    nb: 10000,
  },
  wait: {
    maxErrors: 100,
    maxTime: 10 * 1000,
  },
};

nightmare
  .goto('https://google.com')
  .gremlins(gremlinOptions) // Run gremlins on the page
  .then((errors) => { console.log('Page errors:\n', errors); });

Series of tasks

Alternatively, Nightmare Gremlins also exposes a series of individual functions that can be used on an instance of Nightmare for custom composing via .use:

import Nightmare from 'nightmare';
import * as gremlins from 'nightmare-gremlins';

Nightmare.action('gremlins', gremlins);
const nightmare = Nightmare();

const gremlinOptions = {
  seed: Date.now(),
  unleash: {
    nb: 10000,
  },
  wait: {
    maxErrors: 100,
    maxTime: 10 * 1000,
  },
};

const errors = [];

nightmare
  .use(gremlins.recordErrors(errors))
  .use(gremlins.injectGremlins())
  .use(gremlins.createHorde())
  .use(gremlins.seedHorde(gremlinOptions.seed))
  .use(gremlins.unleashHorde(gremlinOptions.unleash))
  .use(gremlins.waitForGremlins(errors, gremlinOptions.wait))
  .then((errors) => { console.log('Page errors:\n', errors); });

By using a series of tasks, it is possible to add individual steps or functionality:

...

const errors = [];

nightmare
  .use(gremlins.recordErrors(errors))
  .use(gremlins.injectGremlins())
  .evaluate((seed) => {
    const horde = window.gremlins.createHorde();
    horde.seed(seed);
    horde.unleash();
  }, Date.now())
  .use(gremlins.waitForGremlins(errors, gremlinOptions.wait))
  .then(() => { console.log('Page errors:\n', errors); });

Available Actions

Nightmare Gremlins exposes the following tasks (with arguments and defaults):

• recordErrors(Array - []) - adds a listener to the page that will look for all errors and push the error message and stack onto the array passed in
• injectGremlins - injects a specially modified version of the gremlins.js script that supports keyboard entry on Electron
• createHorde - runs a script on the page that creates a horde under the window.horde namespace
• seedHorde(Number|String - Date.now()) - seeds the horde with a specific number to allow for behavior replication
• unleashHorde(Object - {}) - runs a script on the page that unleashes the horde with the options argument having been JSON serialized and deserialized to be passed to the browser
• waitForGremlins(Object - {maxTime: 10000, maxErrors: 100}) - a waiting function that looks for 1 of 2 conditions to be met: time passed is longer than maxTime or the number of errors recorded is greater than maxErrors

Bonus Action

Nightmare Gremlins includes an additional "super task", that is the same as the action used to extend the Nightmare prototype, but intended to be used on an instance instead:

import Nightmare from 'nightmare';
import {unleashGremlins} from 'nightmare-gremlins';

const nightmare = Nightmare();

const gremlinOptions = {
  seed: Date.now(),
  unleash: {
    nb: 10000,
  },
  wait: {
    maxErrors: 100,
    maxTime: 10 * 1000,
  },
};

nightmare
  .use(unleashGremlins(gremlinOptions))
  .then((errors) => { console.log('Page errors:\n', errors); });