subscribe

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  currentUser: Ember.computed(function () {
  	return this.store.createRecord('user', {name:'current'})
  }),
  
  users: Ember.computed(function() {
    return [
      this.store.createRecord('user', {name:'one'}),
      this.store.createRecord('user', {name:'two'}),
      this.store.createRecord('user', {name:'three'}),
      this.store.createRecord('user', {name:'four'}),
      this.store.createRecord('user', {name:'five'})
    ]
  }),
  
  actions: {
    subscribe(user) {
      if (user.followers.mapBy('following.id').includes(this.currentUser.id)) {
        return
      }
      const subscribe = this.store.createRecord('subscribe', {
        follower: this.currentUser,
        following: user
			})
    },
    
    subscribeToCurrentUser(user) {
      if (this.currentUser.followers.mapBy('follower.id').includes(user.id)) {
        return
      }
	    const subscribe = this.store.createRecord('subscribe', {
        follower: user,
        following: this.currentUser
			})
    }
  }
	 
});

models.subscribe.js

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

export default Model.extend({
  follower: belongsTo('user', { inverse: 'followings' }),
  following: belongsTo('user', { inverse: 'followers' })
});

models.user.js

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

export default Model.extend({
  name: attr('string', { defaultValue() { return "asd" } }),
  
  followers: hasMany('subscribe', { inverse: 'following' }),
  followings: hasMany('subscribe', { inverse: 'follower' })
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
current user name: {{currentUser.name}}
{{log currentUser.followers}}
<p>followers: {{currentUser.followers.length}}</p>
<p>followings: {{currentUser.followings.length}}</p>

<hr />

<p>users list</p>
{{#each users as |user|}}
	<div style="border: 1px solid #ddd; margin-bottom: 10px">
  	<p>name: {{user.name}}</p>
	  <p>followers: {{user.followers.length}}</p>
    <p>followings: {{user.followings.length}}</p>
  	<p {{action "subscribe" user}}>subscribe</p>
    <p {{action "subscribeToCurrentUser" user}}>subscribe to current user</p>
  </div>
{{/each}}
<br>
<br>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}