How to access top level meta key from json-api server's 200 response when calling ember data's destroyRecord()

Question

I\'m working on an Ember app that is using Ember Data and the now default json-api adapter.

According to the json-api spec (http://jsonapi.org/format/#crud-deleting)

Answer 1

After upgrading to Ember 2.6.1 and Ember 2.6.1 I was no longer able to access the store._metadataFor property.

To get access to the metadata from a particular call I now override the serializer for the model and add a meta property to the model itself that simply passes through the metadata.

As an example I have a record type called vote which when saved returns some metadata.

For the model I do the following:

// Vote Model (/app/models/vote)
export default DS.Model.extend({
  vote: DS.attr('number'),
  // Since i don't provide a transform the values for meta are passed through in
  // raw form
  meta: DS.attr()
});

Then in the serializer for the vote model I do the following:

// Vote serializer (/app/serializers/vote)
import DS from "ember-data";

export default DS.JSONAPISerializer.extend({
  normalizeSaveResponse(store, primaryModelClass, payload, id, requestType) {
    // The metadata in the payload does get processed by default and will be
    // placed into a top level `meta` key on the returned documentHash
    let documentHash = this._super(store, primaryModelClass, payload, id, requestType);

    // Make sure we always have an empty object assigned to the meta attribute
    if(typeof(payload.meta) !== 'object'){
      payload.meta = {};
    }

    // Move the metadata into the attributes hash for the model
    documentHash.data.attributes.meta = payload.meta;

    return documentHash;
  }
});

Note that in the above example I'm only adding in metadata to the vote model when making a save call to the store. If you wanted to always add in the metadata then you would override the normalize method instead of the normalizeSaveResponse method.

Then you can access a meta field in the results of your save call.

let vote = self.store.createRecord('vote', {
   vote: voteValue
});

vote.save().then(function(result){
   // this will now contain your metadata
   console.info(result.get('meta'));
});