How to setup environments for Cypress. Io

When using Cypress for end-to-end testing, correctly setting and managing environment variables is crucial. Environment variables enable us to use different configurations across various environments (such as development, testing, and production) without modifying the code. Below are several methods to set environment variables in Cypress:

1. Through cypress.json Configuration File

Cypress allows direct setting of environment variables in its configuration file cypress.json. This is a straightforward approach, particularly suitable for variables that rarely change. For example:

json
{
  "baseUrl": "http://localhost:3000",
  "env": {
    "login_email": "user@example.com",
    "login_password": "password123"
  }
}

In test code, we can access these variables using Cypress.env('login_email') and Cypress.env('login_password').

2. Through Command Line

We can pass environment variables via the command line when launching Cypress tests. This is ideal for temporarily modifying variables or using specific variables in isolated test runs. For example:

bash
cypress run --env host=localHost,api_key=123456

After this setup, we can retrieve the corresponding values in tests using Cypress.env('host') and Cypress.env('api_key').

3. Using .env File

For scenarios requiring dynamic management of environment variables, we can leverage the dotenv package to load variables from a .env file. First, install dotenv:

bash
npm install dotenv

Then, in the Cypress plugin file cypress/plugins/index.js, load and configure dotenv:

javascript
require('dotenv').config()

module.exports = (on, config) => {
  config.env.login_email = process.env.LOGIN_EMAIL;
  config.env.login_password = process.env.LOGIN_PASSWORD;

  return config;
};

Next, set these variables in the .env file:

shell
LOGIN_EMAIL=user@example.com
LOGIN_PASSWORD=password123

4. Using Cypress's Environment Variable API

Cypress provides an API for dynamically setting environment variables. We can use these APIs in the plugin file to modify environment variables as needed:

javascript
module.exports = (on, config) => {
  config.env.login_email = 'anotheruser@example.com';
  return config;
};

Summary

Through these methods, Cypress offers flexible and powerful ways to manage environment variables to accommodate diverse testing requirements and environments. In practice, we can select the most appropriate method for setting environment variables based on the specific needs of the project and team.