cypress-autostub

This plugin for the Cypress automation framework alleviates the need to mantain brittle manual mocks by automating the recording and stubbing of requests.

Features

Written in Typescript, strongly typed interfaces for all functions
Global default configs in JS
Local spec configs to override globals
Simple to setup + mantain, plug-n-play auto mocking
CI/Robot friendly (record with an env variable)

API Docs

View the API docs here

Installation

yarn install cypress-autostub

Setup

Setup the plugin along with any desired global settings in cypress/plugins/index.js

// Import the plugin
import { autoStubSetup } from 'cypress-autostub'
 
module.exports = (on, config) => {
    autoStubSetup(on, {
        // Global settings go here
    })
}

Import the stubbing/recording function in your spec files

example.spec.js

import { autoStub } from 'cypress-autostub'
 
describe('Some Feature', () => {
    beforeEach(() => {
        // It can be called from any lifecycle hook
        autoStub()
    })
 
    it('should do the thing', () => {
        // Or from inside a test body
        autoStub()
    })
})

And you are good to go!

Recording

Recording is the process of listening to the network requests that are fired during the execution of your test, and writing the responses to disk.

Mock Files

Mock files are stored on disk in a format that can be directly plugged into cy.route.

The default location for these mock responses to be stored is cypress/mocks but this can be configured globally

The name of the mock file is tied to:

a: The currently executing spec

b: The currently executing test

So if you are running the following test in SomePage/example.spec.js:

describe('MyFeature', () => {
    it('should do a really important thing')
})

The mock file will by default be stored at:

cypress/mocks/SomePage/example/should do a really important thing.json

Note: The spacing in the file name is something I was not entirely happy with , and may be subject to change (or be configurable)

When does it record?

Provided the currently executing spec file has called autoStub , the plugin will begin recording if any of the following are true:

CYPRESS_FORCE_RECORD is set in the environment
forceRecord: true is set globally
forceRecord: true is set locally

Force recording

There is no such thing as "cleaning" up your mock files. If a mock file already exists and the plugin is force recording. The previous mock file will be overwritten.

I believe this is the least error prone method of mantaining the mock files.

Stubbing

Stubbing is very simply calling:

cy.route()

With the data stored in the mock files used as arguments for the cy.route

Troubleshooting

How can I stub/record my fetch requests?

Cypress currently only supports XHR requests. However... Theres an open issue on Cypress with many suggested workarounds for converting your fetch requests into XHR

And more recently theres an experimentalFetchPolyfill option which you can enable in your cypress.json

cypress-autostub