sg-service-registry/lib/ServiceRegistry.js

Simple service registry

'use strict';

Object.defineProperty(exports, "__esModule", {
    value: true
});

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var NULL_INSTANCE = {};

var Service = function () {
    function Service(name, factory) {
        _classCallCheck(this, Service);

        this.name = name;
        this.factory = factory;
        this.instance = NULL_INSTANCE;
    }

    _createClass(Service, [{
        key: 'getInstance',
        value: function getInstance() {
            if (this.instance == NULL_INSTANCE) {
                this.instance = this.factory();
            }

            return this.instance;
        }
    }]);

    return Service;
}();

var ServiceRegistry = exports.ServiceRegistry = function () {
    function ServiceRegistry() {
        _classCallCheck(this, ServiceRegistry);

        this.servicesMap = new Map();
    }

    _createClass(ServiceRegistry, [{
        key: 'register',
        value: function register(name, factory) {
            var _this = this;

            this.servicesMap.set(name, new Service(name, function () {
                return factory(_this);
            }));
        }
    }, {
        key: 'get',
        value: function get(name) {
            if (this.servicesMap.has(name)) {
                return this.servicesMap.get(name).getInstance();
            } else {
                var err = new Error(name + ' is not registered service');
                err.serviceName = name;

                throw err;
            }
        }
    }]);

    return ServiceRegistry;
}();