Custom template or extension point? about offline-plugin

[NekR]

Hi @willdurand,

Yes, you can have custom entry file for SW where you can handle fetch events as you want, but you cannot override behavior for assets listed in caches option. i.e. if you do some API request and want to handle them in SW, just set ServiceWorker.entry option to some JS file, like this:

var OfflinePlugin = require('offline-plugin');

module.exports = {
  // ...

  plugins: [
    // ... other plugins

    new OfflinePlugin({
      // All options are optional
      caches: 'all',
      scope: '/',
      updateStrategy: 'all',
      version: 'v1',

      ServiceWorker: {
        output: 'sw.js',
        entry: 'sw-handler.js'
      },

      AppCache: {
        directory: 'appcache/'
      }
    })
  ]
  // ...
}

and in sw-handler.js:

self.addEventListener('fetch', () => {
  // ...
});

Is it what you wanted?

[NekR]

Okay, I see what you do in your fork. So basically your SPA and for all (some?) requests server returns contents of / and you want same for SW, right? Yeah, it would be unfortunate to cache page for every such request separately.

[willdurand]

So basically you SPA and for all (some?) requests server returns contents of / and you want same for SW, right? Yeah, it would be unfortunate to cache page for every such request separately.

Exactly! The SPA has a single entrypoint (/) and uses the URI to determine which data to load (e.g. /123). This works well online, but I want to be able to refresh the page offline, and still get the content. That is why redirecting any request matching (/<identifier>) to the cached version of / is interesting to me.

Should the sw-handler.js file be a modified version of sw-template.js?

[NekR]

Should the sw-handler.js file be a modified version of sw-template.js?

No, it's an additional file to generated SW, it does not replace anything. Unfortunately there is no way at a moment to alter sw-template.js 😒

[willdurand]

Ok, great. Thank you for your answers. I am not sure to be able to only leverage the sw-handler.js file right now, but it is definitely good to know :)

[NekR]

Tracking cache mapping issue here now: #59
Not sure about custom templates though, it reduces whole point of this plugin then since it's an internal thing which depends on particular version of the plugin. I guess just forking plugin and adopt template for your app is fine.