Handle JSON Body After save() on a Model - ember.js

Question

In an application using the standard Ember 2.0 DS.JSONAPISerializer, the default behaviour for the REST API responding to a save() is "to return an empty object ({})."[1]
In my case, my REST API performs some changes to the data—including assigning a bigserial int64 ID from Postgres and processing text entry to Markdown (much, much faster than Ember can). This should (has to be) synchronous/blocking.
Is there an idiomatic approach to handling the response from save() on the default DS.JSONAPISerializer so that a (the) returned JSON model is stored in Ember's cache?
From what I can see I should be overriding normaliseSaveResponse to achieve this when accepting a response from the server. It's not immediately clear how I should set the fields of the "just saved" model with the server-provided values, however:
// app/models/item.js - simplified
export default DS.Model.extend({
id: DS.attr("number"),
title: DS.attr(),
body: DS.attr(),
// Only populated in the server response
rendered: DS.attr(),
createdDate: DS.attr("date"),
normalizeSaveResponse: function(store, primaryType, payload, id, requestType) {
// What goes here to deserialize the response into the model?
this.id = payload.item[i].id,
this.title = payload.item[i].title,
this.body = payload.item[i].rendered,
}
});
To sum:
I need to populate the model's ID field with a serial ID from the server as a response to save()
I also need to populate the rendered field with Markdown
Date fields, etc with server validated timestamps
Does this work when saving a single item AND multiple items?
If there's a better way to achieve this - e.g. a different method - I'm open to suggestions. The desire is to have additional validation/transforms happen on the server, return the 'corrected' response, and then have Ember save it in its own store => transition to /model/:id.

Answer 1

Just to close this out: Ember Data's default behaviour is to populate the fields (empty or not) in your model with the response JSON, provided your data has the correct structure for your adapter (i.e. RESTAdapter)
e.g.
A model like the below using the RESTAdapter:
export default DS.Model.extend({
id: DS.attr("number"),
title: DS.attr(),
body: DS.attr(),
// Only populated in the server response
rendered: DS.attr(),
// Only populated in the server response
createdDate: DS.attr("date"),
});
... will have the rendered and createdDate fields populated by the server provided your response looks like the below, with one exception (noted):
{
// This can be pluralized regardless of a single item or array response as Ember can deserialize it regardless
"posts": [{
"id": 1,
"title": "I'm Running to Reform the W3C's Tag",
"body": "Yehuda Katz",
"rendered": "<some markdown>",
// snake_case - not suitable by default
"created_at": "2015-09-08T20:31:09Z"
}]
}
You can fix this by overriding the keyForAttribute method on your serializer:
// app/serializers/application.js
export default DS.RESTSerializer.extend({
keyForAttribute: function(key) {
return Ember.String.decamelize(key);
}
});
Ref: http://emberigniter.com/fit-any-backend-into-ember-custom-adapters-serializers/