backoff-polling

controllers.application.js

import Ember from 'ember';
import { task, timeout } from 'ember-concurrency';

export default Ember.Controller.extend({
  pollModelWithCustomStuff: task(function*() {
		let poller = backoffPoller(() => model.reload());

    while (get(model, 'isRunning')) {
      // Do custom stuff before polling
      yield poller.poll();
      // Do custom stuff after polling
    }
    
    // Do stuff after it's done
  }),
  
  pollModelWithoutFancyStuff: task(function*() {
		yield backoffPoller(() => model.reload())
    	.pollUntil(() => !get(model, 'isRunning'));

    // Do stuff after it's done
  }),
});

  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
function backoffPoller(callback, options) {
  return BackoffPoller.create({ callback, ...options });
}

const BackoffPoller = Ember.Object.extend({
  baseInterval: 250,
  maxInterval: 60 * 1000,
  retryCount: 0,
  
  callback: null,
  
  poll() {
    return this.get('_poll').perform(...arguments);
  },
  
  pollUntil() {
    return this.get('_pollUntil').perform(...arguments);
  },
  
  _poll: task(function*() {
    const { retryCount, baseInterval, maxInterval, callback } = this;

    this.incrementProperty('retryCount');

    if (retryCount > 0) {
      yield timeout(Math.min(baseInterval, baseInterval * Math.pow(1.25, retryCount - 1)));
    }
    
    return callback();
  }),
  
  _pollUntil: task(function*(condition) {
    while (!(yield condition())) {
      yield this.poll();
    }
  }),
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.13.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-concurrency": "*"
  }
}