[Ember.js] Custom API request

adapters-post.js

import RESTAdapter from 'ember-data/adapters/rest';

export default RESTAdapter.extend({
  
  /**
   * @param {DS.Model} model
   * @param {JSON} serializedCommentData
   * @returns {*}
   */
  postComment(model, serializedCommentData) {
    
    // http://example.com/posts/5/comments
    const url = this.buildURL('post', model.get('id')) + "/comments";
    
    return this.ajax(url, 'POST', {
      data: {
        'comment': serializedCommentData
      }
    });
  }
});

controllers-post.js

import Controller from 'ember-controller';

export default Controller.extend({

  actions: {
  
    submitForm(commentText) {
      
      // Post model already there (from route)
      var post = this.get('model');
      
      post.createComment({ text: commentText }).then((commentRecord) => {
        alert('Yahoo! Comment created');
      });
      
    }
    
  }
  
});

models-comment.js

import Model from 'ember-data/model';
import attr from 'ember-data/attr';
import { belongsTo } from 'ember-data/relationships';

export default Model.extend({
  text: attr('string'),
  post: belongsTo()
});

models-post.js

import Model from 'ember-data/model';
import attr from 'ember-data/attr';
import { hasMany } from 'ember-data/relationships';

/**
 * For example, we have instance of 'post' model
 * If we want create comment in this 'post', we do:
 * 
 * post.createComment({
 *    text: 'example text of comment'  
 * });
 */
export default Model.extend({
  
  title: attr('string'),
  
  comments: hasMany(),

  /** 
   * [POST] /posts/{id}/comments
   *
   * @param {JSON} rawData
   * @returns {Promise}
   */
  createComment(rawData) {
    
    // this.constructor.modelName = 'post'
    const adapter = this.store.adapterFor(this.constructor.modelName); 
    
    // Create record, and serialize before sending
    const commentRecord = this.store.createRecord('comment', rawData); 
    let serializedCommentData = commentRecord.serialize();

    // Make ajax request [POST]
    return adapter.postComment(this, serializedCommentData).then((responseData) => {
      
      let commentData = responseData.comment; 
      
      let commentSerializer = this.store.serializerFor('comment');
      let CommentModel = this.store.modelFor('comment');
      
      // Normalize response and set Data into commentRecord (what is created earlier)
      commentSerializer.normalize(CommentModel, commentData, 'comment');
      commentRecord.setProperties(commentData);
      commentRecord.transitionTo('saved');
      
      return commentRecord;
      
    });
  }

});