• function

makeFindOne

 

can.Model.makeFindOne: function(findOneData) -> findOne

Returns the external findOne method given the implemented findOneData function.

can.Model.findOne is implemented with a String, ajax settings object, or findOneData function. If it is implemented as a String or ajax settings object, those values are used to create a findOneData function.

The findOneData function is passed to makeFindOne. makeFindOne should use findOneData internally to get the raw data for the request.

Returns

{function(params, success, error)}

Returns function that implements the external API of findOne.

Use

makeFindOne can be used to implement base models that perform special behavior. makeFindOne is passed a findOneData function that retrieves raw data. It should return a function that when called, uses the findOneData function to get the raw data, convert them to model instances with models.

Caching

The following uses makeFindOne to create a base CachedModel:

CachedModel = can.Model.extend({
  makeFindOne: function(findOneData){
    // A place to store requests
    var cachedRequests = {};

    return function(params, success, error){
      // is this not cached?
      if(! cachedRequests[JSON.stringify(params)] ) {
        var self = this;
        // make the request for data, save deferred
        cachedRequests[JSON.stringify(params)] = 
          findOneData(params).then(function(data){
            // convert the raw data into instances
            return self.models(data)
          })
      }
      // get the saved request
      var def = cachedRequests[JSON.stringify(params)]
      // hookup success and error
      def.then(success,error)
      return def;
    }  
  }
},{})

The following Todo model will never request the same todo twice:

Todo = CachedModel({
  findOne: "/todos/{id}"
},{})

// widget 1
Todo.findOne({id: 5})

// widget 2
Todo.findOne({id: 5})