cache_manifest.js

//Convenience array of status values
var cacheStatusValues = [];
cacheStatusValues[0] = 'uncached';
cacheStatusValues[1] = 'idle';
cacheStatusValues[2] = 'checking';
cacheStatusValues[3] = 'downloading';
cacheStatusValues[4] = 'updateready';
cacheStatusValues[5] = 'obsolete';

// Listeners for all possible events
var cache = window.applicationCache;
cache.addEventListener('cached', logEvent, false);
cache.addEventListener('checking', logEvent, false);
cache.addEventListener('downloading', logEvent, false);
cache.addEventListener('error', logEvent, false);
cache.addEventListener('noupdate', logEvent, false);
cache.addEventListener('obsolete', logEvent, false);
cache.addEventListener('progress', logEvent, false);
cache.addEventListener('updateready', logEvent, false);

// Log every event to the console
function logEvent(e) {
    var online, status, type, message;
    online = (isOnline()) ? 'yes' : 'no';
    status = cacheStatusValues[cache.status];
    type = e.type;
    message = 'online: ' + online;
    message += ', event: ' + type;
    message += ', status: ' + status;
    if (type === 'error' && navigator.onLine) {
        message += ' There was an unknown error, check your Cache Manifest.';
    }
    log('' + message);
}

function log(s) {
    console.log(s);
}

function isOnline() {
    return navigator.onLine;
}

if (!jQuery('html').attr('manifest')) {
    log('No Cache Manifest listed on the  tag.');
}

// Swap in newly download files when update is ready
cache.addEventListener('updateready', function (e) {
    // Don't perform "swap" if this is the first cache
    if (cacheStatusValues[cache.status] !== 'idle') {
        cache.swapCache();
        log('Swapped/updated the Cache Manifest.');
    }
}
, false);

// These two functions check for updates to the manifest file
function checkForUpdates() {
    cache.update();
}

function autoCheckForUpdates() {
    setInterval(function () {
        cache.update();
    }, 10000);
}