Testing your PWA score with Google Lighthouse

Chrome-based browsers provide together with the developer tools a utility called Lighthouse, specifically designed to test and rate web pages, and the readiness of PWAs. To access this tool, after you have opened your application in the browser, follow these steps:

1. Open the developer tools (by pressing F12 in Windows/Linux, Fn + F12 in Mac, or through the browser menu).
2. Click the Lighthouse menu toward the further right.
3. Select Mobile or Desktop, plus make sure the Progressive Web App category is checked.
4. Click Analyze page load in the top-right corner of the tool.

The developer tools should look something like this:

Figure 6.7 – Lighthouse utility

The tool will run a number of tests, and each different category will display a rating, as well as a detailed list of items that have either passed or failed. If our application does not qualify to be a PWA, the items marked in red...