fearphage / backbone.cacheit

Fetch caching made super simple in Backbone.

backbone.cacheit v0.0.1

Created by Tim Branyen @tbranyen.

This is useful for when you have Models and Collections that once data is fetched you can operate with the same dataset throughout the lifetime of your application. Whatever route your application starts with can safely call the fetch method to get the data into the instances.

Tested with Underscore, Backbone and jQuery. You can swap out jQuery with a custom configuration or substitute Underscore with Lo-Dash.

Documentation

Every fetch method is patched to return a Deferred, instead of the jqXHR object in jQuery.ajax. If you call fetch multiple times while it is fetching or after it's fetched, you will always get the same Deferred and it will not make additional requests.

Cancelling is super simple, just add the reload option:

fetch({ reload: true });

optionally you can make a Model or Collection always reload by doing the following (works with Models too):

Backbone.Collection.extend({
  reload: true
}):

Since you're getting a brand new deferred and nothing ever happens to the old one you can be assured that fetch callbacks will only trigger after the most recent fetch has completed.

If you want use underscore.deferred or some other implementation you can specify an override to swap out that dependency.

Backbone.Collection.prototype.fetch.deferred = function() {
  return _.Deferred();
};

Notes on SafeSync

It's entirely possible that requests will come back out of order if you use the { reload: true } option. This is most likely not your intention. If you agree, you should put the following plugin into your project. CacheIt will work seamlessly.

https://github.com/amccloud/backbone-safesync

Release notes

0.0.1

• Initial beta release.