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NodeAutoFetchableMixin

Makes use of the identifier of the related node to:

  • check if the model or collection can be fetched; it checks only if the related node is fetchable by default
  • fetch the model or collection automatically when the identifier of the related node changes (if requested); the default event to listen to is 'change:id'

How to apply the mixin to a model​

var MyCollection = Backbone.Collection.extend({

  constructor: function MyCollection(models, options) {
    Backbone.Collection.prototype.constructor.apply(this, arguments);
    this
      .makeNodeConnectable(options)
      .makeFetchable(options)
      .makeNodeAutoFetchable(options);
  }
  
});

NodeConnectableMixin.mixin(MyCollection.prototype);
FetchableMixin.mixin(MyCollection.prototype);
NodeAutoFetchableMixin.mixin(MyCollection.prototype);

This mixin us usually comined together with the NodeConnectableMixin or with another cumulated mixin which includes it and also with the with the FetchableMixin to prevent parallel fetches. If you need all these three mixins, have a look at the NodeResourceMixin, which combines these three together.

How use the mixin​

// Enable watching for the model identifier changes
var connector = new Connector(...),
    node = new NodeModel({id: 2000}, {connector: connector}),
    collection = new MyCollection(undefined, {
      node: node,
      autofetch: true
    });

// A fetch of the collection will take place, notifying the event
// listeners about its progress
node.set('id', 2000);

makeNodeAutoFetchable(options) : this​

Must be called in the constructor to initialize the mixin functionality. Expects the Backbone.Model constructor options passed in.

Recognized option properies:

autofetch : If set to true, it executes the fetch method whenever the node model identifier changes (boolean, undefined is the default)

autofetchEvent : Can override the event to listen to on the node model for the automatic fetching (string, 'change:id' by default)

automateFetch(boolean) : void​

Truns on or off the automatic fetching depending if you pass true or false in. It can be used to change the behaviour set up by the constructor.

isFetchable() : boolean​

Returns true if the model or collection is fetchable, otherwise false. It requires the related node not only fetchable, but also having the 'id' property set. (While nodes can be fetched using other properties, like volumes by 'type', for example, other resources related to the node may not.) If the model or collection is not fetchable, the automatic fetching will not take place.

See Also​

NodeConnectableMixin, FetchableMixin, NodeResourceMixin