Ember Engines

This is a quickstart guide inspired by ember engine quickstart on how to set up an ember engine in Vault!

Create a new in-repo engine:

ember g in-repo-engine <engine-name>

This blueprint in-repo engine command will add a new folder lib/<engine-name> and add the engine to our main app’s package.json

Engine’s package.json:

{
  "name": "<engine-name>",

  "dependencies": {
    "ember-cli-htmlbars": "*",
    "ember-cli-babel": "*"
  },

  "ember-addon": {
    "paths": ["../core"]
  }
}

For our application, we want to include the ember-addon path ../core

By adding this ember-addon path, we are able to share elements between your in-repo addon and the Vault application¹.

Configure your Engine

In the engine’s index.js file:

/**
 * Copyright IBM Corp. 2016, 2025
 * SPDX-License-Identifier: BUSL-1.1
 */

/* eslint-disable node/no-extraneous-require */
const { buildEngine } = require('ember-engines/lib/engine-addon');

module.exports = buildEngine({
  name: '<engine-name>',
  lazyLoading: {
    enabled: false,
  },
  isDevelopingAddon() {
    return true;
  },
});

Within your Engine’s config/environment.js file:

/**
 * SPDX-License-Identifier: BUSL-1.1
 */

// config/environment.js

'use strict';

module.exports = function (environment) {
  const ENV = {
    modulePrefix: '<engine-name>',
    environment: environment,
  };

  return ENV;
};

Within your Engine’s addon/engine.js file:

/**
 * SPDX-License-Identifier: BUSL-1.1
 */

import Engine from '@ember/engine';

import loadInitializers from 'ember-load-initializers';
import Resolver from 'ember-resolver';

import config from './config/environment';

const { modulePrefix } = config;

export default class <EngineName>Engine extends Engine {
  modulePrefix = modulePrefix;
  Resolver = Resolver;
  dependencies = {
    services: ['app-router', 'store', 'secret-mount-path', 'flash-messages'],
    externalRoutes: ['secrets'],
  };
}

loadInitializers(<EngineName>Engine, modulePrefix);

Service Dependencies:

The services in the example above are common services that we often use in our engines. If your engine requires other services from the main application, add them to the services array.

Notes:

• Service dependencies are OPTIONAL. If your engine does not use any external services, you do not need to include a services dependency array.
• Remember to include any dependencies here in the engine's dependencies in app/app.js

External Route Dependencies:

The external route dependencies allow you to link to a route outside of your engine. In this example, we list 'secrets' in the externalRoute and the route is defined in the app.js file.

Notes:

• In order to link to the other routes in the main app using the LinkToExternal component from your engine, you need to add the route to the app/app.js and your engine’s addon/engine.js. More information on Linking to An External Context..

Additional info about your engine's application.hbs:

• Optional step: Add some text in the engine’s application.hbs file (to see if your engine was set up correctly).
• NOTE: Most of our existing engines do not keep the generated application.hbs template file. If nothing will be added to it and it remains as just an {{outlet}} it can safely be removed.

Register your engine with our main application:

In our app/app.js file in the engines object, add your engine’s name and dependencies. The router service must be referenced via an alias within engines. The pattern is to use app-router as the alias, see example below.

/**
 * SPDX-License-Identifier: BUSL-1.1
 */

import Application from '@ember/application';
import Resolver from 'ember-resolver';
import loadInitializers from 'ember-load-initializers';
import config from 'vault/config/environment';

export default class App extends Application {
	...
  engines = {
    <engine-name>: {
      dependencies: {
        services: [{ 'app-router': 'router' }, 'store', 'secret-mount-path', 'flash-messages', <any-other-dependencies-you-have>],
        externalRoutes: {
          secrets: 'vault.cluster.secrets.backends',
        },
      },
    },
  };
}

loadInitializers(App, config.modulePrefix);

If you used ember g in-repo-engine <engine-name> to generate the engine’s blueprint, it should have added this.mount(<engine-name>) to the main app’s router.js file (this adds your engine and its associated routes). *Move this.mount(<engine-name>) to match your engine’s route structure. For more information about Routable Engines.

Add engine path to ember-addon section of main app package.json

  "ember-addon": {
    "paths": [
      "lib/core",
      "lib/your-new-engine"
    ]
  },

Important Notes:

• Anytime a new engine is created, you will need to pnpm install and RESTART ember server!
• To add package.json dependencies or devDependencies, you can copy + paste the dependency into corresponding sections. Most of the time, we will want to use "*" in place of the version number to ensure all the dependencies have the latest version.

Common blueprint commands:

• Generating In-repo engines routes: ember generate route <route-name> --in-repo <in-repo-name> - generates tests and route files and templates
• Remove In-repo engines routes: ember destroy route <route-name> --in-repo <in-repo-name> - removes tests and route files and templates
• Generating In-repo engines components: ember generate component <component-name> --in-repo <in-repo-name>- generates tests and component files and templates
• Remove In-repo engines components: ember destroy component <component-name> --in-repo <in-repo-name>- removes tests and component files and templates