import ObservableStore from 'obs-store' /** * An ObservableStore that can composes a flat * structure of child stores based on configuration */ export default class ComposableObservableStore extends ObservableStore { /** * Create a new store * * @param {Object} [initState] - The initial store state * @param {Object} [config] - Map of internal state keys to child stores */ constructor (initState, config) { super(initState) this.updateStructure(config) } /** * Composes a new internal store subscription structure * * @param {Object} [config] - Map of internal state keys to child stores */ updateStructure (config) { this.config = config this.removeAllListeners() for (const key in config) { if (Object.prototype.hasOwnProperty.call(config, key)) { config[key].subscribe((state) => { this.updateState({ [key]: state }) }) } } } /** * Merges all child store state into a single object rather than * returning an object keyed by child store class name * * @returns {Object} - Object containing merged child store state */ getFlatState () { let flatState = {} for (const key in this.config) { if (Object.prototype.hasOwnProperty.call(this.config, key)) { const controller = this.config[key] const state = controller.getState ? controller.getState() : controller.state flatState = { ...flatState, ...state } } } return flatState } }