Backbone poller is a simple utility that allows polling on any Backbone model or collection.

Some modern browsers and servers support Web Sockets or long polling (comet) and allow advanced polling models.

However, in many cases it is sufficient to run a standard http request every few seconds to keep the client synced with the server. For instance, basic operations such as checking for new messages in a mailbox.

Backbone poller helps with these cases:

• Allows you to poll without extending your base backbone models or collections
• Is 100% compliant with any Backbone model or collection.

The annotated source code is available online.

• Development Version 4.6kb, Uncompressed with Comments
• Production Version 1.8kb, Minified and Gzipped

// to initialize:
var poller = Backbone.Poller.get(model_or_collection);
poller.start()

// or
var poller = Backbone.Poller.get(model_or_collection).start()

// to stop:
poller.stop();

require(['path/to/backbone.poller', 'path/to/Collection'], function(Poller, Collection) {
  var collection = new Collection();
  var poller = Poller.get(collection).start();
});

var options = {

  // default delay is 1000ms
  delay: 300,

  // run after the first delay. defaults to false
  delayed: true,

  // condition for keeping polling active (when this stops being true, polling will stop)
  condition: function(model){
      return model.get('active') === true;
  },

  // We can pass data to a fetch request
  data: {fields: "*", sort: "name asc"}
}
var poller = Backbone.Poller.get(model, options);

var poller = Backbone.Poller.get(model);
poller.on('success', function(model){
  console.info('another successful fetch!');
});
poller.on('complete', function(model){
  console.info('hurray! we are done!');
});
poller.on('error', function(model){
  console.error('oops! something went wrong');
}
poller.start()

To stop we can manually call poller.stop() or we can make the conditional function return false:

var poller = Backbone.Poller.get(model);
poller.stop() // manually stops the poller

var options = {
  condition: function(model){
      return model.get('active') === true;
  }
};
var poller = Backbone.Poller.get(model, options);
model.set('active', false); // will programmatically stop the poller

var isActive = poller.active() // boolean;

Altering options will stop the current running poller and will require manual start. This method removes all existing options and set the new options assigned.

var poller = Backbone.Poller.get(model, {delay: 100}).start();

// stops the poller, replaces the options, and then starts
poller.set({delay: 300}).start();

Backbone.Poller.reset();

Copyright (c) 2012 Uzi Kilon, Splunk Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.