Improve Cypress testing against non-functioning app.js

Where to find the issue

Cypress test suite for cwa-website https://github.com/corona-warn-app/cwa-website/tree/master/cypress

Describe the issue

Running the Cypress test suite against the production webserver https://www.coronawarn.app on May 10, 2022 when there were multiple website issues occurring (see #2870) failed to identify any issue. The test suite passed although at the time the Google Chrome console was showing the error:

www.coronawarn.app/:1 Refused to execute script from 'https://www.coronawarn.app/assets/js/app.js' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled.

This error condition prevented many essential functions on the website from being available.

Steps to reproduce

Local clone

To simulate the mime problem locally, test with a removed app.js JavaScript file. From a bash prompt at the root of the cloned cwa-website repository execute:

1. npm run test:open
2. Manually delete /public/assets/js/app.js from generated local directory under cwa-website
3. Go to page http://localhost:8000/en/analysis/ in web browser and confirm “No data to display” in dashboard graphs (showing that web is broken)
4. In Cypress test runner click on “Run 6 integration tests”
5. Note that 87 tests pass and 0 tests fail, even though app.js is not available

Production server

To run the Cypress test suite against the production server, navigate in a bash prompt to the root of the cloned cwa-website repository and execute

npx cypress run -c baseUrl=https://coronawarn.app or npx cypress open -c baseUrl=https://coronawarn.app to run individual tests

Suggested enhancement

Add a new Cypress test to check for correct mime types.

[MikeMcC399]

• PR #2890 has been merged, so this enhancement request has now been fulfilled.

[MikeMcC399]

@Ein-Tim

Will the PR extend the test suite to check for the absence of app.js (that’s what you described in your steps to reproduce) or will it check for malfunctions of app.js?

You can view the test code in PR #2890 now. Its purpose is to check the mime types, which was the root cause of the problem https://github.com/corona-warn-app/cwa-website/issues/2870. If app.js is missing, the test will also fail with a 404 error, however that was not a problem in production, I just used the file deletion as a way to simulate the issue.