config/repositories/EnvironmentRepository.js

//--------------------------------------------------------
//-- Node IoC - Config - Config Grammar
//--------------------------------------------------------

import __     from '@absolunet/private-registry';
import dotenv from 'dotenv';


/**
 * Environment repository that exposes all environment variables.
 *
 * @memberof config.repositories
 * @hideconstructor
 */
class EnvironmentRepository {

	/**
	 * Class dependencies: <code>['app', 'evaluator']</code>.
	 *
	 * @type {Array<string>}
	 */
	static get dependencies() {
		return ['app', 'evaluator'];
	}

	/**
	 * @inheritdoc
	 * @private
	 */
	init() {
		this.setFromFile(this.app.basePath('.env'));
	}

	/**
	 * Set environment values from given file.
	 *
	 * @param {string} file - The .env file to load the specific environment variable from.
	 */
	setFromFile(file) {
		const { error, parsed } = dotenv.config({ path: file });
		const environment = Object.entries(error ? {} : parsed).reduce((object, [key, value]) => {
			object[key] = value;

			return object;
		}, process.env); // eslint-disable-line no-process-env
		__(this).set('env', environment);
	}

	/**
	 * Get all loaded environment variables.
	 *
	 * @returns {object<string, *>} The environment variables.
	 */
	all() {
		return { ...__(this).get('env') || {} };
	}

	/**
	 * Get single environment variable.
	 * Value will be automatically cast as null, a boolean, a number or a string.
	 * The first valid value will be returned.
	 *
	 * @param {string} key - The environment variable name.
	 * @param {null|boolean|number|string}[defaultValue] - The default value to use if the environment variable is not defined.
	 * @returns {boolean|null|number|string} The environment variable value.
	 */
	get(key, defaultValue = null) {
		if (!this.has(key)) {
			return defaultValue;
		}

		return this.evaluator.evaluate(this.all()[key]);
	}

	/**
	 * Check if environment variable was defined.
	 *
	 * @param {string} key - The environment variable name.
	 * @returns {boolean} Indicates if the variable exists in environment.
	 */
	has(key) {
		return Object.prototype.hasOwnProperty.call(this.all(), key);
	}

}


export default EnvironmentRepository;