Unable to use value from an Ember Data store in template - ember.js

Question

I'm building a simple application using Ember v1.8.1, Ember CLI 0.1.15 and Ember Data 1.0.0-beta.15 in an attempt to learn the basics of Ember.js. Data is coming from a simple REST API, so I'm using the DS.RESTAdapter and DS.RESTSerializer. The payload is normalized in the serializer, because the API doesn't properly wrap its data in the required hashes.
I'm trying to implement an edit route, but am unable to populate the form fields of that template or even display a simple value. My index route, displaying a list of posts, works as expected, but edit doesn't for some reason.
Using {{title}} in my template doesn't render the value, but outputs a string of unexpected data, something along the lines of: <my-app#model:post::ember413:21>. I'm probably passing something improperly from the route or elsewhere, but I don't know what and where exactly.
Below is some of my relevant code:
app/router.js
import Ember from 'ember';
import config from './config/environment';
var Router = Ember.Router.extend({
location: config.locationType
});
Router.map(function() {
this.route('login');
this.resource('posts', function() {
this.route('add');
this.route('view', { path: ':post_id'});
this.route('edit', { path: ':post_id/edit'});
});
});
export default Router;
app/routes/posts/edit.js
import Ember from 'ember';
import AuthenticatedRouteMixin from 'simple-auth/mixins/authenticated-route-mixin';
export default Ember.Route.extend(AuthenticatedRouteMixin, {
model: function(params){
return this.store.find('post', params.post_id);
}
});
app/routes/posts/index.js
import Ember from 'ember';
import AuthenticatedRouteMixin from 'simple-auth/mixins/authenticated-route-mixin';
export default Ember.Route.extend(AuthenticatedRouteMixin, {
model: function(){
return this.store.find('post');
}
});
app/controllers/posts/edit.js
import Ember from 'ember';
export default Ember.ObjectController.extend();
app/serializers/application.js
import Ember from "ember";
import DS from "ember-data";
export default DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin, {
primaryKey: 'ID',
attrs: {
author: { embedded: 'always' }
},
extractSingle: function(store, type, payload, id) {
payload = { post : payload };
return this._super(store, type, payload, id);
},
extractArray: function(store, type, payload) {
payload = { posts : payload };
return this._super(store, type, payload);
},
serializeIntoHash: function(hash, type, record, options) {
Ember.merge(hash, this.serialize(record, options));
}
});
app/templates/edit.hbs
<div class="page">
<div class="page-content">
<h2>{{title}}</h2>
{{{content}}}
</div>
</div>
app/templates/index.hbs
<div class="page">
<div class="page-content">
<ul>
{{#each}}
<li>
<h2>{{title}}</h2>
{{{content}}}
</li>
{{/each}}
</ul>
</div>
</div>
Having looked at some examples the above should work, so probably there's an error in the serializer. In the route I can access values from the store however. The following logs the expected data when used in the model method of my edit.js route:
this.store.find('post', params.post_id).then(function(post) {
console.log(post.get('title'));
});
UPDATE: Here is a JS Bin recreating most of the application without Ember CLI. The behaviour is exactly the same as on my local machine; the edit route doesn't properly show the content value (title works, for some reason). When I swap to fixtures instead of the API output the problem remains the same. Also the model in the bin doesn't map to all the values returned by the API, but that doesn't seem to make a difference.
UPDATE 2: Seems the content entry of the returned payload is causing the problems, when I rename the key it's displayed correctly in the edit template. Didn't realise this before, because I was so focussed on getting the content value to display and forgot to test other values. Not sure why it happens only happens on a nested route though and with that particular keyword.
UPDATE 3: If I understand correctly, this might be related to an outstanding issue for Ember Data, there's a proposal for reporting such collisions as well.