# Extending
CodeceptJS provides API to run custom code before and after the test and inject custom listeners into the event system.
# Plugins
Plugins allow to use CodeceptJS internal API to extend functionality. Use internal event dispatcher, container, output, promise recorder, to create your own reporters, test listeners, etc.
CodeceptJS includes built-in plugins which extend basic functionality and can be turned on and off on purpose. Taking them as examples (opens new window) you can develop your custom plugins.
A plugin is a basic JS module returning a function. Plugins can have individual configs which are passed into this function:
const defaultConfig = {
someDefaultOption: true
}
module.exports = function(config) {
config = Object.assign(defaultConfig, config);
// do stuff
}
Plugin can register event listeners or hook into promise chain with recorder. See API reference (opens new window).
To enable your custom plugin in config add it to plugins
section. Specify path to node module using require
.
"plugins": {
"myPlugin": {
"require": "./path/to/my/module",
"enabled": true
}
}
require
- specifies relative path to a plugin file. Path is relative to config file.enabled
- to enable this plugin.
If a plugin is disabled (enabled
is not set or false) this plugin can be enabled from command line:
npx codeceptjs run --plugin myPlugin
Several plugins can be enabled as well:
npx codeceptjs run --plugin myPlugin,allure
# Example: Execute code for a specific group of tests
If you need to execute some code before a group of tests, you can mark these tests with a same tag. Then to listen for tests where this tag is included (see test object api).
Let's say we need to populate database for a group of tests.
// populate database for slow tests
const event = require('codeceptjs').event;
module.exports = function() {
event.dispatcher.on(event.test.before, function (test) {
if (test.tags.indexOf('@populate') >= 0) {
recorder.add('populate database', async () => {
// populate database for this test
})
}
});
}
# Example: Check URL before running a test
If you want to share bootstrap script or run multiple bootstraps, it's a good idea to wrap that script into a plugin. Plugin can also execute JS before tests but you need to use internal APIs to synchronize promises.
const { recorder } = require('codeceptjs');
module.exports = function(options) {
event.dispatcher.on(event.all.before, function () {
recorder.startUnlessRunning(); // start recording promises
recorder.add('do some async stuff', async () => {
// your code
});
});
}
# API
Use local CodeceptJS installation to get access to codeceptjs
module
CodeceptJS provides an API which can be loaded via require('codeceptjs')
when CodeceptJS is installed locally.
These internal objects are available:
codecept
(opens new window): test runner classconfig
(opens new window): current codecept configevent
(opens new window): event listenerrecorder
(opens new window): global promise chainoutput
(opens new window): internal printercontainer
(opens new window): dependency injection container for tests, includes current helpers and support objectshelper
(opens new window): basic helper classactor
(opens new window): basic actor (I) class
API reference (opens new window) is available on GitHub. Also please check the source code of corresponding modules.
# Event Listeners
CodeceptJS provides a module with event dispatcher and set of predefined events (opens new window).
It can be required from codeceptjs package if it is installed locally.
const event = require('codeceptjs').event;
module.exports = function() {
event.dispatcher.on(event.test.before, function (test) {
console.log('--- I am before test --');
});
}
Available events:
event.test.before(test)
- async whenBefore
hooks from helpers and from test is executedevent.test.after(test)
- async after each testevent.test.started(test)
- sync at the very beginning of a test. Passes a current test object.event.test.passed(test)
- sync when test passedevent.test.failed(test, error)
- sync when test failedevent.test.finished(test)
- sync when test finishedevent.suite.before(suite)
- async before a suiteevent.suite.after(suite)
- async after a suiteevent.step.before(step)
- async when the step is scheduled for executionevent.step.after(step)
- async after a stepevent.step.started(step)
- sync when step starts.event.step.passed(step)
- sync when step passed.event.step.failed(step, err)
- sync when step failed.event.step.finished(step)
- sync when step finishes.event.step.comment(step)
- sync fired for comments likeI.say
.event.bddStep.before(bddStep)
- async when the gherkin step is scheduled for executionevent.bddStep.after(bddStep)
- async after a gherkin stepevent.all.before
- before running testsevent.all.after
- after running testsevent.all.result
- when results are printedsync - means that event is fired in the moment of action happens.
async - means that event is fired when an actions is scheduled. Use
recorder
to schedule your actions.
For further reference look for currently available listeners (opens new window) using event system.
# Test Object
Test events provide a test object with following fields:
title
title of a testbody
test function as a stringopts
additional test options like retries, and otherspending
true if test is scheduled for execution and false if a test has finishedtags
array of tags for this testfile
path to a file with a test.steps
array of executed steps (available only intest.passed
,test.failed
,test.finished
event)skipInfo
additional test options when test skippedmessage
string with reason for skip
description
string with test body and others
# Step Object
Step events provide step objects with following fields:
name
name of a step, like 'see', 'click', and othersactor
current actor, in most cases itI
helper
current helper instance used to execute this stephelperMethod
corresponding helper method, in most cases is the same asname
status
status of a step (passed or failed)prefix
if a step is executed insidewithin
block contain within text, like: 'Within .js-signup-form'.args
passed arguments
# Recorder
To inject asynchronous functions in a test or before/after a test you can subscribe to corresponding event and register a function inside a recorder object. Recorder (opens new window) represents a global promises chain.
Provide a function description as a first parameter, function should return a promise:
const event = require('codeceptjs').event;
const recorder = require('codeceptjs').recorder;
module.exports = function() {
event.dispatcher.on(event.test.before, function (test) {
const request = require('request');
recorder.add('create fixture data via API', function() {
return new Promise((doneFn, errFn) => {
request({
baseUrl: 'http://api.site.com/',
method: 'POST',
url: '/users',
json: { name: 'john', email: '[email protected]' }
}), (err, httpResponse, body) => {
if (err) return errFn(err);
doneFn();
}
});
}
});
}
Whenever you execute tests with --verbose
option you will see registered events and promises executed by a recorder.
# Output
Output module provides 4 verbosity levels. Depending on the mode you can have different information printed using corresponding functions.
default
: prints basic information usingoutput.print
steps
: toggled by--steps
option, prints step executiondebug
: toggled by--debug
option, prints steps, and debug information withoutput.debug
verbose
: toggled by--verbose
prints debug information and internal logs withoutput.log
It is recommended to avoid console.log
and use output.* methods for printing.
const output = require('codeceptjs').output;
output.print('This is basic information');
output.debug('This is debug information');
output.log('This is verbose logging information');
# Container
CodeceptJS has a dependency injection container with Helpers and Support objects. They can be retrieved from the container:
let container = require('codeceptjs').container;
// get object with all helpers
let helpers = container.helpers();
// get helper by name
let WebDriver = container.helpers('WebDriver');
// get support objects
let support = container.support();
// get support object by name
let UserPage = container.support('UserPage');
// get all registered plugins
let plugins = container.plugins();
New objects can also be added to container in runtime:
let container = require('codeceptjs').container;
container.append({
helpers: { // add helper
MyHelper: new MyHelper({ config1: 'val1' });
},
support: { // add page object
UserPage: require('./pages/user');
}
})
Container also contains current Mocha instance:
let mocha = container.mocha();
# Config
CodeceptJS config can be accessed from require('codeceptjs').config.get()
:
let config = require('codeceptjs').config.get();
if (config.myKey == 'value') {
// run hook
}
# Custom Runner
πΊ Watch this (opens new window) material on YouTube
CodeceptJS can be imported and used in custom runners. To initialize Codecept you need to create Config and Container objects.
const { codecept: Codecept } = require('codeceptjs');
const config = { helpers: { WebDriver: { browser: 'chrome', url: 'http://localhost' } } };
const opts = { steps: true };
const codecept = new Codecept(config, options);
codecept.init(testRoot);
// run tests
try {
await codecept.bootstrap();
codecept.loadTests('*_test.js');
await codecept.run(test);
} catch (err) {
printError(err);
process.exitCode = 1;
} finally {
await codecept.teardown();
}
In this way Codecept runner class can be extended.