How to change the baseUrl via command line with Cypress

Learn a simple technique to perform automated tests in different environments, overwriting the Cypress configuration

Resuming the series "Pinches of Cypress", I decided to bring a simple but recurring theme in discussion forums about testing automation.

Imagine that you need to run the same set of end-to-end tests against a local development environment, in a staging environment, and then in production.

Let's say the URLs for the environments are as follows:

• http://localhost:8000
• https://example.com/my-app-staging
• https://example.com/my-app

And in the Cypress settings file, the baseUrl property has the value http://localhost:8000. That is, it points to the local development environment.

In the package.json file, we could have the following scripts:

"scripts": {
  "test": "cypress run",
  "test:staging": "cypress run --config baseUrl=https://example.com/my-app-staging",
  "test:prod": "cypress run --config baseUrl=https://example.com/my-app"
}

Finally, at the terminal, or even in a continuous integration pipeline, execute the following commands to run the tests against the different environments.

• npm test (or npm t - short version) - to run tests against the local development environment
• npm run test:staging - to run the tests against the staging environment
• and npm run test:prod - to run the tests in production

That's it!

And just as baseUrl can be overwritten, so can other configurations.

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Tell me, what else would you like to see in the series "Pinches of Cypress"?

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This post was originally published in Portuguese on the Talking About Testing blog.

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Would you like to learn about test automation with Cypress? I was hoping you could get to know my online courses on Udemy. Happy testing! 🎉

Comments

[SheenaVanPunk]

Maybe this helps someone:
changing the mailHogUrl parameter with using --config flag doesn't work if you are using the cypress-mailhog package.
But it works if you set the mailHogUrl as an Environment variable 🎉 Then in the npm script we can call it with using --env flag:
--env mailHogUrl=your-custom-mailhog-url

[Walmyr]

That's a great tip! Thanks for sharing, @sheenavanpunk .

[SheenaVanPunk]

Useful tip!
Does the same logic work for any parameter from cypress.json file? For example, I have a mailhog url that I would need to alter in different environments.
--config parameter_name

[Walmyr]

Hi, @sheenavanpunk ,
I know you can change other configurations via the command line too. I'd recommend giving it a try.