title: Handling File Uploads When Offline With Service Worker
body: <p>We have a web app (built using AngularJS) that we're gradually adding PWA 'features' too (service worker, launchable, notifications, etc). One of the features our web app has is the ability to complete a web form while offline. At the moment, we store the data in IndexedDB when offline, and simply encourage the user to push that data to the server once they're online ("This form is saved to your device. Now you're back online, you should save it to the cloud..."). We will do this automatically at some point, but that's not necessary at the moment.</p>
  
  <p>We are adding a feature to these web forms, whereby the user will be able to attach files (images, documents) to the form, perhaps at several points throughout the form.</p>
  
  <p>My question is this - is there a way for service worker to handle file uploads? To somehow - perhaps - store the path to the file to be uploaded, when offline, and push that file up once the connection has been restored? Would this work on mobile devices, as do we have access to that 'path' on those devices? Any help, advice or references would be much appreciated.</p>