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tuxracer/service-worker.js

Created October 13, 2016 20:49
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  1. tuxracer created this gist Oct 13, 2016.
    47 changes: 47 additions & 0 deletions service-worker.js
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,47 @@
    var version = 'app-v1';

    var expectedCaches = [version];

    self.oninstall = () => console.log('Installed version:', version);

    self.onfetch = (event) => {
    event.respondWith(
    // Check cache for request
    caches.match(event.request)
    .then((cachedResponse) => {
    // If we have a cached response return it immediately unless this is an API request.
    // For those we'll only fallback to a cached response as a last resort
    if (cachedResponse &&
    cachedResponse.type !== 'error' &&
    !event.request.url.match('/api|jsonp')
    ) {
    console.log('Returning cached response ' + event.request.url, cachedResponse);
    return cachedResponse;
    }

    // Try to make the request
    return fetch(event.request.clone())
    .then((response) => {
    if (!response || response.status !== 200) {
    throw new Error('Invalid response ' + event.request.url);
    }

    return response.clone();
    })
    .then((response) => {
    const clonedRequest = event.request.clone();
    const clonedResponse = response.clone();

    // Cache the response
    caches.open(version).then((cache) => cache.put(clonedRequest, clonedResponse));

    // Return the live response
    console.log("Returning live response for", event.request.url);
    return response;
    }, (err) => {
    // Fallback to cached response if request fails
    return cachedResponse;
    });
    })
    );
    };