Learning Progressive Web Apps: Building Modern Web Apps Using Service Workers

7. Passing Data between Service Workers and Web Applications

Service workers and web apps have a symbiotic relationship on modern browsers that support service workers; the two work closely together to deliver an improved experience for users. So far, the only interactions I showed between web apps and service workers are situations in which the service worker helps the web app, such as by managing resource fetching and processing push notifications as they arrive. In this chapter, I show how to pass data between a service worker and a web app running in a browser (desktop or mobile). This data communication goes both ways: from a service worker to the web app, from a web app to the service worker, or even from the service worker to all browser ...