Can't get it work 'ember-data' - ember.js

Question

App = Ember.Application.create();
App.Store = DS.Store.extend({
revision: 12,
adapter: 'DS.FixtureAdapter'
});
App.Router.map(function() {
this.resource('about')
this.resource('posts')
});
App.PostsRoute = Ember.Route.extend({
model: function() {
return this.store.find('post');
// i tried return App.Post.find(); didn't work.
}
});
App.Post = DS.Model.extend({
title: DS.attr('string'),
author: DS.attr('string'),
intro: DS.attr('string'),
extended: DS.attr('string'),
publishedAt: DS.attr('date')
});
App.Post.FIXTURES = [{
id: 1,
title: "Title 1",
author: "Anonim",
publishedAt: new Date('21-04-2014'),
intro: "Introduction",
extended: "It is a long story"
}, {
id: 2,
title: "Title 2",
author: "Anonymous 2",
publishedAt: new Date('12-04-2014'),
intro: "Introduction for ID 2",
extended: "It is a long story for ID 2"
}];
And handlebars (I wll try to use hbs next time)
<script type="text/x-handlebars">
<nav class="top-bar" data-topbar>
<ul class="title-area">
<li class="name">
<h1>Starter Kit</h1>
</li>
<li class="toggle-topbar menu-icon">Menu</li>
</ul>
<section class="top-bar-section">
<ul class="left">
<li>{{#link-to 'posts'}}Posts{{/link-to}}</li>
<li>{{#link-to 'about'}}About{{/link-to}}</li>
</ul>
</section>
</nav>
{{outlet}} <!--it is a placeholder to show templates-->
</script>
<script type="text/x-handlebars" id="posts">
<div class="row">
<div class="large-12 columns">
<h3>Posts Page</h3>
<h4>Dynamic Posts Page</h4>
{{#each model}}
<ul>
<li>
<p>{{title}}</p>
<p>{{author}}</p>
<p>{{intro}}</p>
<p>{{extended}}</p>
<p>{{date}}</p>
</li>
</ul>
{{/each}}
</div>
</div>
{{outlet}}
</script>
<script type="text/x-handlebars" id="about">
<div class="row">
<div class="large-12 columns">
<h3>About page</h3>
<p>About</p>
</div>
</div>
{{outlet}}
</script>
The error i get
GET http://localhost/posts 404 (Not Found) jquery.js:26
Error while loading route: undefined
After reading introductions both on ember.js offical site and other community sites, I tried to follow the ember guide following by this link, however, i couldn't make it work.

Answer 1

You should assign DS.FixtureAdapter itself rather than a string. You can also remove the revision property since that's not really necessary anymore.
Change:
App.Store = DS.Store.extend({
revision: 12,
adapter: 'DS.FixtureAdapter'
});
To:
App.Store = DS.Store.extend({
adapter: DS.FixtureAdapter
});

Answer 2

Your error explains exactly why it's not working. The GET request failed because http://localhost/posts doesn't exist. You should read more about Ember's adapters and their conventions.