Adapt authoring tool UI documentation

v1.0.0-rc.4

adapt-authoring-core/lib/App.js

  1. import AbstractModule from './AbstractModule.js'
  2. import DependencyLoader from './DependencyLoader.js'
  3. import { fileURLToPath } from 'url'
  4. import fs from 'fs'
  5. import path from 'path'
  6. import Utils from './Utils.js'
  8. let instance
  9. /**
  10.  * Core functionality
  11.  * @namespace core
  12.  */
  13. /**
  14.  * The main application class
  15.  * @memberof core
  16.  * @extends {AbstractModule}
  17.  */
  18. class App extends AbstractModule {
  19.   /**
  20.    * The singleton instance. Self-initialises it if there isn't one.
  21.    * @type {App}
  22.    */
  23.   static get instance () {
  24.     if (!instance) instance = new App()
  25.     return instance
  26.   }
  28.   /** @override */
  29.   constructor () {
  30.     const rootDir = process.env.ROOT_DIR ?? process.cwd()
  31.     const adaptJson = JSON.parse(fs.readFileSync(path.join(rootDir, Utils.metadataFileName)))
  32.     const packageJson = JSON.parse(fs.readFileSync(path.join(rootDir, Utils.packageFileName)))
  33.     super(null, { ...packageJson, ...adaptJson, name: 'adapt-authoring-core', rootDir })
  34.   }
  36.   /** @override */
  37.   async init () {
  38.     /**
  39.      * Reference to the passed arguments (parsed for easy reference)
  40.      * @type {Object}
  41.      */
  42.     this.args = Utils.getArgs()
  43.     /**
  44.      * Instance of App instance (required by all AbstractModules)
  45.      * @type {App}
  46.      */
  47.     this.app = this
  48.     /**
  49.      * Reference to the DependencyLoader instance
  50.      * @type {DependencyLoader}
  51.      */
  52.     this.dependencyloader = new DependencyLoader(this)
  54.     /** @ignore */ this._isStarting = false
  56.     const configRootDir = this.getConfig('rootDir')
  57.     if (configRootDir) /** @ignore */this.rootDir = configRootDir
  59.     let startError
  60.     try {
  61.       await this.start()
  62.     } catch (e) {
  63.       startError = e
  64.     }
  65.     const failedMods = this.dependencyloader.failedModules
  66.     if (failedMods.length) this.log('warn', `${failedMods.length} module${failedMods.length === 1 ? '' : 's'} failed to load: ${failedMods}. See above for details`)
  67.     if (startError) {
  68.       process.exitCode = 1
  69.       throw new Error('Failed to start App')
  70.     }
  71.   }
  73.   /**
  74.    * The Adapt module dependencies and their configs
  75.    * @type {Object}
  76.    */
  77.   get dependencies () {
  78.     return this.dependencyloader.configs
  79.   }
  81.   /**
  82.    * Starts the app
  83.    * @return {Promise} Resolves when the app has started
  84.    */
  85.   async start () {
  86.     if (this._isReady) throw new Error('warn', 'cannot start app, already started')
  87.     if (this._isStarting) throw new Error('warn', 'cannot start app, already initialising')
  89.     this._isStarting = true
  91.     await this.dependencyloader.load()
  93.     this._isStarting = false
  94.   }
  96.   /**
  97.    * Enables waiting for other modules to load
  98.    * @param {...String} modNames Names of modules to wait for
  99.    * @return {Promise} Resolves when specified module has been loaded
  100.    */
  101.   async waitForModule (...modNames) {
  102.     const results = await Promise.all(modNames.map(m => this.dependencyloader.waitForModule(m)))
  103.     return results.length > 1 ? results : results[0]
  104.   }
  106.   /** @override */
  107.   setReady (error) {
  108.     this._isStarting = false
  109.     super.setReady(error)
  110.   }
  111. }
  113. export default App