Offlibrary for Workbox

Workbox is how most production service workers are built: precaching for the app shell, routing, and caching strategies. If yours is one of them, you don’t need a second service worker or a second fetch listener to use Offlibrary. offlibrary/workbox plugs it into Workbox:

Export	What it is	Use it when
`offlibraryMatch` + `offlibraryHandler()`	A ready-made Workbox route	You want “stored files from the device, everything else from the network” in one line
`OfflibraryPlugin`	A Workbox plugin	You already have a media route and strategy, and want it to know about downloads
`initOfflibrary()`	Background Fetch handling without a `fetch` listener	Always, if you use Background Fetch (the default in Chromium)

import { precacheAndRoute } from 'workbox-precaching';
import { registerRoute } from 'workbox-routing';
import { NetworkOnly } from 'workbox-strategies';
import { initOfflibrary, offlibraryMatch, offlibraryHandler } from 'offlibrary/workbox';

initOfflibrary();
precacheAndRoute(self.__WB_MANIFEST);
registerRoute(offlibraryMatch, offlibraryHandler({ fallback: new NetworkOnly() }));

The page side is the same as without Workbox: createOfflibrary() and download().

Why a dedicated entry

Workbox caches what the network sends while the app runs. Offlibrary stores what the user chose to keep: whole episodes, lessons and map packs, downloaded with Background Fetch or a resumable fallback, under quota and LRU rules. To play those files offline, the service worker must find them and answer Range requests, inside Workbox’s routing. That’s what this entry does, with the same matching and Range logic as offlibrarySW().

No Workbox inside

offlibrary/workbox imports nothing from Workbox. The plugin and the route handler are plain objects that match Workbox’s interfaces, and they’re type-checked against workbox-core’s own types in CI. So:

no peer dependency, and never a second copy of Workbox in your bundle;
works with Workbox 6 and 7, bundled or loaded with workbox-sw (tested against Workbox 7.4);
the route alone costs ~1.7 KB gzipped; the whole entry, Background Fetch handling included, ~4.2 KB.

It lives in the main offlibrary package as a subpath export, so versions can’t drift apart.

Offlibrary for Workbox

Why a dedicated entry

No Workbox inside

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