Resolving fingerprinted assets using generateAssetMap

Ember CLI
5

Well, I’ve basically read all the issues on Github and they just say “yeah we need to do it better”, but it hasn’t happened so far. :smile:

I’ve only run into two problems:

  1. The assetMap is on the CDN as well in my case, so it has to be retrieved from there
  2. The initializer was timing out all my tests, so I substituted a “dummy” service that just retuns the passed asset path in dev/testing

This is my version:

import Ember from 'ember';
import ENV from 'volders/config/environment';

export function initialize(container, application) {
  var AssetMap;

  application.deferReadiness();

  if (ENV.APP.CDN_PATH === '') {
    // use an asset map stub in development / testing
    AssetMap = Ember.Object.extend({
      resolve(name) {
        return name;
       }
    });

    container.register('assetMap:main', AssetMap, { singleton: true });
    application.inject('service:assets', 'assetMap', 'assetMap:main');
    application.advanceReadiness();
  } else {
    AssetMap = Ember.Object.extend();

    var promise = new Ember.RSVP.Promise(function(resolve, reject) {
      var assetMapURL = `${ENV.APP.CDN_PATH}assets/assetMap.json`;
      Ember.$.getJSON(assetMapURL, resolve).fail(reject);
    });

    promise.then(function(assetMap) {
      AssetMap.reopen({
        assetMap: assetMap,
        resolve: function(name) {
          // lookup asset in asset map; if not found, try the asset name itself
          return `${assetMap.prepend}${assetMap.assets[name]}` || name;
        }
      });
    }, function() {
      AssetMap.reopen({
        resolve: function(name) {
          return name;
        }
      });
    }).then(function() {
      container.register('assetMap:main', AssetMap, { singleton: true });
      application.inject('service:assets', 'assetMap', 'assetMap:main');
      application.advanceReadiness();
    });
  }
}

export default {
  name: 'asset-map',
  initialize: initialize
};

I set the ENV.APP.CDN_PATH in my config/environment.js by reading a JSON file that I also reuse in the ember-cli-build.js, so I don’t have to change paths in more than location.

edit: actually there was another problem in that the assetMap has a “prepend” entry that has to be prefixed to the actual asset lookup. Maybe this is something that changed recently. I updated my example.