var keepWarm = require('keep-warm');

/* Params:
 * key: a unique string
 * fetch: a function returning a Promise
 * interval: cache will be updated every interval ms
 */
keepWarm('myKey', function() {
    // does something async and returns a Promise
}, 15000);

/* Params
 * key: the key you originally passed to keepWarm
 * Use when you want the data synchronously and don't care about a failure when the cache has not been initially populated
 */
var myData = keepWarm.get('myKey');

/* Params
 * key: the key you originally passed to keepWarm
 * Use when you want to wait for the cache to be populated if it's not
 */
var myData;
keepWarm.getAsync('myKey').then(function(value) {
    myData = value;
});