attrs not working for json-api-serializer

[digabit]

Defining an attrs map when using JSONAPISerializer does not seem to be working.

For example if I have the following model:

// app/models/product.js
export default DS.Model.extend({
    productNumber: DS.attr('string')
});

and the following serializer:

// app/serializers/product.js
export default DS.JSONAPISerializer.extend({
  attrs: {
    productNumber: 'partNumber'
  }
});

and JSON:API data like this coming over the wire:

{
    "data": [{
           "type": "products",
           "id": "15296",
           "attributes": {
               "partNumber": "3004-787"
           },
           "relationships": ...,
           "links": ...
        }]
}

The serializer does not assign '3004-787' to the productNumber property of the new product.

The root cause seems to be in json-api-serializer which uses normalizeUsingDeclaredMapping from json-serializer. That method looks for the keys on attrs at the root level of the hash. In JSON:API these properties are inside the attributes property. So it seems like we need to override normalizeUsingDeclaredMapping and do something like this:

// serializers/product.js
 normalizeUsingDeclaredMapping: function (typeClass, hash) {
    var get = Ember.get;
    var attrs = get(this, "attrs");
    var payloadKey, key;

    if (attrs) {
      for (key in attrs) {
        payloadKey = this._getMappedKey(key);
        if (!hash.attributes || !hash.attributes.hasOwnProperty(payloadKey)) {
          continue;
        }

        if (payloadKey !== key) {
          hash.attributes[key] = hash.attributes[payloadKey];
          delete hash.attributes[payloadKey];
        }
      }
    }
  }

This does in fact solve the problem in my environment. I didn't submit this as a pull request because I think there are probably other areas which I'm not familliar with but which need to be fixed as well. Like when serializing this property we need to do the reverse to construct the proper JSON from the model. Also does attrs apply to relationship names as well? Seems like it might have the same problem. Thanks

[HeroicEric]

@digabit If your server is sending the key as partNumber, I think you'll want to use:

export default DS.JSONAPISerializer.extend({
  attrs: {
    productNumber: { key: 'partNumber' }
  }
});

[HeroicEric]

Or maybe you need to do something like:

import DS from 'ember-data';

const { JSONAPISerializer } = DS;

export default JSONAPISerializer.extend({
  keyForAttribute(attr) {
    if (attr === 'partNumber') {
      attr = 'productNumber';
    }

    return this._super(...arguments);
  }
});

[digabit]

Thanks for the suggestions. Your first idea doesn't seem to work. Your second suggestion does give another way to do it although you need to:

return this._super(attr);

However what you are proposing are work-arounds. This is exactly what the attrs mapping is supposed to be for and it doesn't seem to be working.

[pangratz]

@digabit I think you should open a PR so this is fixed in the JSONAPISerializer. The normalizeUsingDeclaredMapping normalizes the keys for attributes and relationships, so this needs to be considered in the fix. I would change this line with something like:

this.normalizeUsingDeclaredMapping(modelClass, resourceHash.attributes);
this.normalizeUsingDeclaredMapping(modelClass, resourceHash.relationships);

There should likely be checks added, since normalizeUsingDeclaredMapping expects a hash as second argument, but attributes or relationships might be undefined on the JSONAPI document.

[digabit]

@pangraz Ah yeah that is cleaner than overriding the whole method. Alright I'll put together a PR.

[HeroicEric]

@digabit my bad. I misunderstood. I didn't realize normalizeUsingDeclaredMapping was a thing. I thought you added that.

[digabit]

@HeroicEric No problem!

[pangratz]

Hey @digabit, kindly asking if you had any chance yet for the PR?

[weinberg]

Hi @pangratz - just filed the PR here: #3845 (using my personal account). Thanks

[bmac]

I believe this issue is solved by #3847.