Debugging

The Ember Inspector is a browser extension that makes it easy to understand and debug your Ember.js application. To learn more, check out the dedicated guide.

import Application from '@ember/application';

export default class App extends Application {
  // Basic logging, e.g. "Transitioned into 'post'"
  LOG_TRANSITIONS = true;

  // Extremely detailed logging, highlighting every internal
  // step made while transitioning into a route, including
  // `beforeModel`, `model`, and `afterModel` hooks, and
  // information about redirects and aborted transitions
  LOG_TRANSITIONS_INTERNAL = true;
}

ENV.APP.LOG_VIEW_LOOKUPS = true;

ENV.APP.LOG_ACTIVE_GENERATION = true;

This option logs all the lookups that are done to the console. Custom objects you've created yourself have a tick, and Ember generated ones don't.

It's useful for understanding which objects Ember is finding when it does a lookup and which it is generating automatically for you.

import Application from '@ember/application';

export default class App extends Application {
  LOG_RESOLVER = true;
}

In addition to what is described in the Handling Deprecations guide, you can turn on the following settings:

Ember.ENV.RAISE_ON_DEPRECATION = true;
Ember.ENV.LOG_STACKTRACE_ON_DEPRECATION = true;

import Ember from 'ember';
import fetch from 'fetch';
// ...
Ember.onerror = function(error) {
  fetch('/error-notification', {
    method: 'POST',
    body: JSON.stringify({
      stack: error.stack,
      otherInformation: 'exception message'
    })
  });
}

If you are using imports with Ember, be sure to import the console:

Ember = {
  imports: {
    Handlebars: Handlebars,
    jQuery: $,
    console: window.console
  }
};

Backburner.js has support for stitching the stacktraces together so that you can track down where an error thrown by Ember.run.later is being initiated from. Unfortunately, this is quite slow and is not appropriate for production or even normal development.

To enable full stacktrace mode in Backburner, and thus determine the stack of the task when it was scheduled onto the run loop, you can set:

Ember.run.backburner.DEBUG = true;

Once the DEBUG value is set to true, when you are at a breakpoint you can navigate back up the stack to the flush method in and check the errorRecordedForStack.stack value, which will be the captured stack when this job was scheduled.