workbox-cdn/workbox/workbox-window.dev.umd.js

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
  typeof define === 'function' && define.amd ? define(['exports'], factory) :
  (global = global || self, factory(global.workbox = {}));
}(this, function (exports) { 'use strict';

  try {
    self['workbox:window:4.3.0'] && _();
  } catch (e) {} // eslint-disable-line

  /*
    Copyright 2019 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  /**
   * Sends a data object to a service worker via `postMessage` and resolves with
   * a response (if any).
   *
   * A response can be set in a message handler in the service worker by
   * calling `event.ports[0].postMessage(...)`, which will resolve the promise
   * returned by `messageSW()`. If no response is set, the promise will not
   * resolve.
   *
   * @param {ServiceWorker} sw The service worker to send the message to.
   * @param {Object} data An object to send to the service worker.
   * @return {Promise<Object|undefined>}
   *
   * @memberof module:workbox-window
   */

  var messageSW = function messageSW(sw, data) {
    return new Promise(function (resolve) {
      var messageChannel = new MessageChannel();

      messageChannel.port1.onmessage = function (evt) {
        return resolve(evt.data);
      };

      sw.postMessage(data, [messageChannel.port2]);
    });
  };

  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);
    }
  }

  function _createClass(Constructor, protoProps, staticProps) {
    if (protoProps) _defineProperties(Constructor.prototype, protoProps);
    if (staticProps) _defineProperties(Constructor, staticProps);
    return Constructor;
  }

  function _inheritsLoose(subClass, superClass) {
    subClass.prototype = Object.create(superClass.prototype);
    subClass.prototype.constructor = subClass;
    subClass.__proto__ = superClass;
  }

  function _assertThisInitialized(self) {
    if (self === void 0) {
      throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
    }

    return self;
  }

  try {
    self['workbox:core:4.3.0'] && _();
  } catch (e) {} // eslint-disable-line

  /*
    Copyright 2018 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  /**
   * The Deferred class composes Promises in a way that allows for them to be
   * resolved or rejected from outside the constructor. In most cases promises
   * should be used directly, but Deferreds can be necessary when the logic to
   * resolve a promise must be separate.
   *
   * @private
   */

  var Deferred =
  /**
   * Creates a promise and exposes its resolve and reject functions as methods.
   */
  function Deferred() {
    var _this = this;

    this.promise = new Promise(function (resolve, reject) {
      _this.resolve = resolve;
      _this.reject = reject;
    });
  };

  /*
    Copyright 2019 Google LLC
    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  var logger = function () {
    var inGroup = false;
    var methodToColorMap = {
      debug: "#7f8c8d",
      // Gray
      log: "#2ecc71",
      // Green
      warn: "#f39c12",
      // Yellow
      error: "#c0392b",
      // Red
      groupCollapsed: "#3498db",
      // Blue
      groupEnd: null // No colored prefix on groupEnd

    };

    var print = function print(method, args) {
      var _console2;

      if (method === 'groupCollapsed') {
        // Safari doesn't print all console.groupCollapsed() arguments:
        // https://bugs.webkit.org/show_bug.cgi?id=182754
        if (/^((?!chrome|android).)*safari/i.test(navigator.userAgent)) {
          var _console;

          (_console = console)[method].apply(_console, args);

          return;
        }
      }

      var styles = ["background: " + methodToColorMap[method], "border-radius: 0.5em", "color: white", "font-weight: bold", "padding: 2px 0.5em"]; // When in a group, the workbox prefix is not displayed.

      var logPrefix = inGroup ? [] : ['%cworkbox', styles.join(';')];

      (_console2 = console)[method].apply(_console2, logPrefix.concat(args));

      if (method === 'groupCollapsed') {
        inGroup = true;
      }

      if (method === 'groupEnd') {
        inGroup = false;
      }
    };

    var api = {};

    var _arr = Object.keys(methodToColorMap);

    var _loop = function _loop() {
      var method = _arr[_i];

      api[method] = function () {
        for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
          args[_key] = arguments[_key];
        }

        print(method, args);
      };
    };

    for (var _i = 0; _i < _arr.length; _i++) {
      _loop();
    }

    return api;
  }();

  /*
    Copyright 2019 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  /**
   * A minimal `EventTarget` shim.
   * This is necessary because not all browsers support constructable
   * `EventTarget`, so using a real `EventTarget` will error.
   * @private
   */

  var EventTargetShim =
  /*#__PURE__*/
  function () {
    /**
     * Creates an event listener registry
     *
     * @private
     */
    function EventTargetShim() {
      // A registry of event types to listeners.
      this._eventListenerRegistry = {};
    }
    /**
     * @param {string} type
     * @param {Function} listener
     * @private
     */


    var _proto = EventTargetShim.prototype;

    _proto.addEventListener = function addEventListener(type, listener) {
      this._getEventListenersByType(type).add(listener);
    };
    /**
     * @param {string} type
     * @param {Function} listener
     * @private
     */


    _proto.removeEventListener = function removeEventListener(type, listener) {
      this._getEventListenersByType(type).delete(listener);
    };
    /**
     * @param {Event} event
     * @private
     */


    _proto.dispatchEvent = function dispatchEvent(event) {
      event.target = this;

      this._getEventListenersByType(event.type).forEach(function (listener) {
        return listener(event);
      });
    };
    /**
     * Returns a Set of listeners associated with the passed event type.
     * If no handlers have been registered, an empty Set is returned.
     *
     * @param {string} type The event type.
     * @return {Set} An array of handler functions.
     * @private
     */


    _proto._getEventListenersByType = function _getEventListenersByType(type) {
      return this._eventListenerRegistry[type] = this._eventListenerRegistry[type] || new Set();
    };

    return EventTargetShim;
  }();

  /*
    Copyright 2019 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  /**
   * Returns true if two URLs have the same `.href` property. The URLS can be
   * relative, and if they are the current location href is used to resolve URLs.
   *
   * @private
   * @param {string} url1
   * @param {string} url2
   * @return {boolean}
   */

  var urlsMatch = function urlsMatch(url1, url2) {
    return new URL(url1, location).href === new URL(url2, location).href;
  };

  /*
    Copyright 2019 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */
  /**
   * A minimal `Event` subclass shim.
   * This doesn't *actually* subclass `Event` because not all browsers support
   * constructable `EventTarget`, and using a real `Event` will error.
   * @private
   */

  var WorkboxEvent =
  /**
   * @param {string} type
   * @param {Object} props
   */
  function WorkboxEvent(type, props) {
    Object.assign(this, props, {
      type: type
    });
  };

  function _catch(body, recover) {
    try {
      var result = body();
    } catch (e) {
      return recover(e);
    }

    if (result && result.then) {
      return result.then(void 0, recover);
    }

    return result;
  }

  function _async(f) {
    return function () {
      for (var args = [], i = 0; i < arguments.length; i++) {
        args[i] = arguments[i];
      }

      try {
        return Promise.resolve(f.apply(this, args));
      } catch (e) {
        return Promise.reject(e);
      }
    };
  }

  function _invoke(body, then) {
    var result = body();

    if (result && result.then) {
      return result.then(then);
    }

    return then(result);
  }

  function _await(value, then, direct) {
    if (direct) {
      return then ? then(value) : value;
    }

    if (!value || !value.then) {
      value = Promise.resolve(value);
    }

    return then ? value.then(then) : value;
  }

  function _awaitIgnored(value, direct) {
    if (!direct) {
      return value && value.then ? value.then(_empty) : Promise.resolve();
    }
  }

  function _empty() {}
  // `skipWaiting()` wasn't called. This 200 amount wasn't scientifically
  // chosen, but it seems to avoid false positives in my testing.

  var WAITING_TIMEOUT_DURATION = 200; // The amount of time after a registration that we can reasonably conclude
  // that the registration didn't trigger an update.

  var REGISTRATION_TIMEOUT_DURATION = 60000;
  /**
   * A class to aid in handling service worker registration, updates, and
   * reacting to service worker lifecycle events.
   *
   * @fires [message]{@link module:workbox-window.Workbox#message}
   * @fires [installed]{@link module:workbox-window.Workbox#installed}
   * @fires [waiting]{@link module:workbox-window.Workbox#waiting}
   * @fires [controlling]{@link module:workbox-window.Workbox#controlling}
   * @fires [activated]{@link module:workbox-window.Workbox#activated}
   * @fires [redundant]{@link module:workbox-window.Workbox#redundant}
   * @fires [externalinstalled]{@link module:workbox-window.Workbox#externalinstalled}
   * @fires [externalwaiting]{@link module:workbox-window.Workbox#externalwaiting}
   * @fires [externalactivated]{@link module:workbox-window.Workbox#externalactivated}
   *
   * @memberof module:workbox-window
   */

  var Workbox =
  /*#__PURE__*/
  function (_EventTargetShim) {
    _inheritsLoose(Workbox, _EventTargetShim);

    /**
     * Creates a new Workbox instance with a script URL and service worker
     * options. The script URL and options are the same as those used when
     * calling `navigator.serviceWorker.register(scriptURL, options)`. See:
     * https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerContainer/register
     *
     * @param {string} scriptURL The service worker script associated with this
     *     instance.
     * @param {Object} [registerOptions] The service worker options associated
     *     with this instance.
     */
    function Workbox(scriptURL, registerOptions) {
      var _this;

      if (registerOptions === void 0) {
        registerOptions = {};
      }

      _this = _EventTargetShim.call(this) || this;
      _this._scriptURL = scriptURL;
      _this._registerOptions = registerOptions;
      _this._updateFoundCount = 0; // Deferreds we can resolve later.

      _this._swDeferred = new Deferred();
      _this._activeDeferred = new Deferred();
      _this._controllingDeferred = new Deferred(); // Bind event handler callbacks.

      _this._onMessage = _this._onMessage.bind(_assertThisInitialized(_assertThisInitialized(_this)));
      _this._onStateChange = _this._onStateChange.bind(_assertThisInitialized(_assertThisInitialized(_this)));
      _this._onUpdateFound = _this._onUpdateFound.bind(_assertThisInitialized(_assertThisInitialized(_this)));
      _this._onControllerChange = _this._onControllerChange.bind(_assertThisInitialized(_assertThisInitialized(_this)));
      return _this;
    }
    /**
     * Registers a service worker for this instances script URL and service
     * worker options. By default this method delays registration until after
     * the window has loaded.
     *
     * @param {Object} [options]
     * @param {Function} [options.immediate=false] Setting this to true will
     *     register the service worker immediately, even if the window has
     *     not loaded (not recommended).
     */


    var _proto = Workbox.prototype;
    _proto.register = _async(function (_temp) {
      var _this2 = this;

      var _ref = _temp === void 0 ? {} : _temp,
          _ref$immediate = _ref.immediate,
          immediate = _ref$immediate === void 0 ? false : _ref$immediate;

      {
        if (_this2._registrationTime) {
          logger.error('Cannot re-register a Workbox instance after it has ' + 'been registered. Create a new instance instead.');
          return;
        }
      }

      return _invoke(function () {
        if (!immediate && document.readyState !== 'complete') {
          return _awaitIgnored(new Promise(function (res) {
            return addEventListener('load', res);
          }));
        }
      }, function () {
        // Set this flag to true if any service worker was controlling the page
        // at registration time.
        _this2._isUpdate = Boolean(navigator.serviceWorker.controller); // Before registering, attempt to determine if a SW is already controlling
        // the page, and if that SW script (and version, if specified) matches this
        // instance's script.

        _this2._compatibleControllingSW = _this2._getControllingSWIfCompatible();
        return _await(_this2._registerScript(), function (_this2$_registerScrip) {
          _this2._registration = _this2$_registerScrip;

          // If we have a compatible controller, store the controller as the "own"
          // SW, resolve active/controlling deferreds and add necessary listeners.
          if (_this2._compatibleControllingSW) {
            _this2._sw = _this2._compatibleControllingSW;

            _this2._activeDeferred.resolve(_this2._compatibleControllingSW);

            _this2._controllingDeferred.resolve(_this2._compatibleControllingSW);

            _this2._reportWindowReady(_this2._compatibleControllingSW);

            _this2._compatibleControllingSW.addEventListener('statechange', _this2._onStateChange, {
              once: true
            });
          } // If there's a waiting service worker with a matching URL before the
          // `updatefound` event fires, it likely means that this site is open
          // in another tab, or the user refreshed the page (and thus the prevoius
          // page wasn't fully unloaded before this page started loading).
          // https://developers.google.com/web/fundamentals/primers/service-workers/lifecycle#waiting


          var waitingSW = _this2._registration.waiting;

          if (waitingSW && urlsMatch(waitingSW.scriptURL, _this2._scriptURL)) {
            // Store the waiting SW as the "own" Sw, even if it means overwriting
            // a compatible controller.
            _this2._sw = waitingSW; // Run this in the next microtask, so any code that adds an event
            // listener after awaiting `register()` will get this event.

            Promise.resolve().then(function () {
              _this2.dispatchEvent(new WorkboxEvent('waiting', {
                sw: waitingSW,
                wasWaitingBeforeRegister: true
              }));

              {
                logger.warn('A service worker was already waiting to activate ' + 'before this script was registered...');
              }
            });
          } // If an "own" SW is already set, resolve the deferred.


          if (_this2._sw) {
            _this2._swDeferred.resolve(_this2._sw);
          }

          {
            logger.log('Successfully registered service worker.', _this2._scriptURL);

            if (navigator.serviceWorker.controller) {
              if (_this2._compatibleControllingSW) {
                logger.debug('A service worker with the same script URL ' + 'is already controlling this page.');
              } else {
                logger.debug('A service worker with a different script URL is ' + 'currently controlling the page. The browser is now fetching ' + 'the new script now...');
              }
            }

            var currentPageIsOutOfScope = function currentPageIsOutOfScope() {
              var scopeURL = new URL(_this2._registerOptions.scope || _this2._scriptURL, document.baseURI);
              var scopeURLBasePath = new URL('./', scopeURL.href).pathname;
              return !location.pathname.startsWith(scopeURLBasePath);
            };

            if (currentPageIsOutOfScope()) {
              logger.warn('The current page is not in scope for the registered ' + 'service worker. Was this a mistake?');
            }
          }

          _this2._registration.addEventListener('updatefound', _this2._onUpdateFound);

          navigator.serviceWorker.addEventListener('controllerchange', _this2._onControllerChange, {
            once: true
          }); // Add message listeners.

          if ('BroadcastChannel' in self) {
            _this2._broadcastChannel = new BroadcastChannel('workbox');

            _this2._broadcastChannel.addEventListener('message', _this2._onMessage);
          }

          navigator.serviceWorker.addEventListener('message', _this2._onMessage);
          return _this2._registration;
        });
      });
    });
    /**
     * Resolves to the service worker registered by this instance as soon as it
     * is active. If a service worker was already controlling at registration
     * time then it will resolve to that if the script URLs (and optionally
     * script versions) match, otherwise it will wait until an update is found
     * and activates.
     *
     * @return {Promise<ServiceWorker>}
     */

    /**
     * Resolves with a reference to a service worker that matches the script URL
     * of this instance, as soon as it's available.
     *
     * If, at registration time, there's already an active or waiting service
     * worker with a matching script URL, it will be used (with the waiting
     * service worker taking precedence over the active service worker if both
     * match, since the waiting service worker would have been registered more
     * recently).
     * If there's no matching active or waiting service worker at registration
     * time then the promise will not resolve until an update is found and starts
     * installing, at which point the installing service worker is used.
     *
     * @return {Promise<ServiceWorker>}
     */
    _proto.getSW = _async(function () {
      var _this3 = this;

      // If `this._sw` is set, resolve with that as we want `getSW()` to
      // return the correct (new) service worker if an update is found.
      return _this3._sw || _this3._swDeferred.promise;
    });
    /**
     * Sends the passed data object to the service worker registered by this
     * instance (via [`getSW()`]{@link module:workbox-window.Workbox#getSW}) and resolves
     * with a response (if any).
     *
     * A response can be set in a message handler in the service worker by
     * calling `event.ports[0].postMessage(...)`, which will resolve the promise
     * returned by `messageSW()`. If no response is set, the promise will never
     * resolve.
     *
     * @param {Object} data An object to send to the service worker
     * @return {Promise<Object>}
     */

    _proto.messageSW = _async(function (data) {
      var _this4 = this;

      return _await(_this4.getSW(), function (sw) {
        return messageSW(sw, data);
      });
    });
    /**
     * Checks for a service worker already controlling the page and returns
     * it if its script URL matchs.
     *
     * @private
     * @return {ServiceWorker|undefined}
     */

    _proto._getControllingSWIfCompatible = function _getControllingSWIfCompatible() {
      var controller = navigator.serviceWorker.controller;

      if (controller && urlsMatch(controller.scriptURL, this._scriptURL)) {
        return controller;
      }
    };
    /**
     * Registers a service worker for this instances script URL and register
     * options and tracks the time registration was complete.
     *
     * @private
     */


    _proto._registerScript = _async(function () {
      var _this5 = this;

      return _catch(function () {
        return _await(navigator.serviceWorker.register(_this5._scriptURL, _this5._registerOptions), function (reg) {
          // Keep track of when registration happened, so it can be used in the
          // `this._onUpdateFound` heuristic. Also use the presence of this
          // property as a way to see if `.register()` has been called.
          _this5._registrationTime = performance.now();
          return reg;
        });
      }, function (error) {
        {
          logger.error(error);
        } // Re-throw the error.


        throw error;
      });
    });
    /**
     * Sends a message to the passed service worker that the window is ready.
     *
     * @param {ServiceWorker} sw
     * @private
     */

    _proto._reportWindowReady = function _reportWindowReady(sw) {
      messageSW(sw, {
        type: 'WINDOW_READY',
        meta: 'workbox-window'
      });
    };
    /**
     * @private
     */


    _proto._onUpdateFound = function _onUpdateFound() {
      var installingSW = this._registration.installing; // If the script URL passed to `navigator.serviceWorker.register()` is
      // different from the current controlling SW's script URL, we know any
      // successful registration calls will trigger an `updatefound` event.
      // But if the registered script URL is the same as the current controlling
      // SW's script URL, we'll only get an `updatefound` event if the file
      // changed since it was last registered. This can be a problem if the user
      // opens up the same page in a different tab, and that page registers
      // a SW that triggers an update. It's a problem because this page has no
      // good way of knowing whether the `updatefound` event came from the SW
      // script it registered or from a registration attempt made by a newer
      // version of the page running in another tab.
      // To minimize the possibility of a false positive, we use the logic here:

      var updateLikelyTriggeredExternally = // Since we enforce only calling `register()` once, and since we don't
      // add the `updatefound` event listener until the `register()` call, if
      // `_updateFoundCount` is > 0 then it means this method has already
      // been called, thus this SW must be external
      this._updateFoundCount > 0 || // If the script URL of the installing SW is different from this
      // instance's script URL, we know it's definitely not from our
      // registration.
      !urlsMatch(installingSW.scriptURL, this._scriptURL) || // If all of the above are false, then we use a time-based heuristic:
      // Any `updatefound` event that occurs long after our registration is
      // assumed to be external.
      performance.now() > this._registrationTime + REGISTRATION_TIMEOUT_DURATION ? // If any of the above are not true, we assume the update was
      // triggered by this instance.
      true : false;

      if (updateLikelyTriggeredExternally) {
        this._externalSW = installingSW;

        this._registration.removeEventListener('updatefound', this._onUpdateFound);
      } else {
        // If the update was not triggered externally we know the installing
        // SW is the one we registered, so we set it.
        this._sw = installingSW;

        this._swDeferred.resolve(installingSW); // The `installing` state isn't something we have a dedicated
        // callback for, but we do log messages for it in development.


        {
          if (navigator.serviceWorker.controller) {
            logger.log('Updated service worker found. Installing now...');
          } else {
            logger.log('Service worker is installing...');
          }
        }
      } // Increment the `updatefound` count, so future invocations of this
      // method can be sure they were triggered externally.


      ++this._updateFoundCount; // Add a `statechange` listener regardless of whether this update was
      // triggered externally, since we have callbacks for both.

      installingSW.addEventListener('statechange', this._onStateChange);
    };
    /**
     * @private
     * @param {Event} originalEvent
     */


    _proto._onStateChange = function _onStateChange(originalEvent) {
      var _this6 = this;

      var sw = originalEvent.target;
      var state = sw.state;
      var isExternal = sw === this._externalSW;
      var eventPrefix = isExternal ? 'external' : '';
      var eventProps = {
        sw: sw,
        originalEvent: originalEvent
      };

      if (!isExternal && this._isUpdate) {
        eventProps.isUpdate = true;
      }

      this.dispatchEvent(new WorkboxEvent(eventPrefix + state, eventProps));

      if (state === 'installed') {
        // This timeout is used to ignore cases where the service worker calls
        // `skipWaiting()` in the install event, thus moving it directly in the
        // activating state. (Since all service workers *must* go through the
        // waiting phase, the only way to detect `skipWaiting()` called in the
        // install event is to observe that the time spent in the waiting phase
        // is very short.)
        // NOTE: we don't need separate timeouts for the own and external SWs
        // since they can't go through these phases at the same time.
        this._waitingTimeout = setTimeout(function () {
          // Ensure the SW is still waiting (it may now be redundant).
          if (state === 'installed' && _this6._registration.waiting === sw) {
            _this6.dispatchEvent(new WorkboxEvent(eventPrefix + 'waiting', eventProps));

            {
              if (isExternal) {
                logger.warn('An external service worker has installed but is ' + 'waiting for this client to close before activating...');
              } else {
                logger.warn('The service worker has installed but is waiting ' + 'for existing clients to close before activating...');
              }
            }
          }
        }, WAITING_TIMEOUT_DURATION);
      } else if (state === 'activating') {
        clearTimeout(this._waitingTimeout);

        if (!isExternal) {
          this._activeDeferred.resolve(sw);
        }
      }

      {
        switch (state) {
          case 'installed':
            if (isExternal) {
              logger.warn('An external service worker has installed. ' + 'You may want to suggest users reload this page.');
            } else {
              logger.log('Registered service worker installed.');
            }

            break;

          case 'activated':
            if (isExternal) {
              logger.warn('An external service worker has activated.');
            } else {
              logger.log('Registered service worker activated.');

              if (sw !== navigator.serviceWorker.controller) {
                logger.warn('The registered service worker is active but ' + 'not yet controlling the page. Reload or run ' + '`clients.claim()` in the service worker.');
              }
            }

            break;

          case 'redundant':
            if (sw === this._compatibleControllingSW) {
              logger.log('Previously controlling service worker now redundant!');
            } else if (!isExternal) {
              logger.log('Registered service worker now redundant!');
            }

            break;
        }
      }
    };
    /**
     * @private
     * @param {Event} originalEvent
     */


    _proto._onControllerChange = function _onControllerChange(originalEvent) {
      var sw = this._sw;

      if (sw === navigator.serviceWorker.controller) {
        this.dispatchEvent(new WorkboxEvent('controlling', {
          sw: sw,
          originalEvent: originalEvent
        }));

        {
          logger.log('Registered service worker now controlling this page.');
        }

        this._controllingDeferred.resolve(sw);
      }
    };
    /**
     * @private
     * @param {Event} originalEvent
     */


    _proto._onMessage = function _onMessage(originalEvent) {
      var data = originalEvent.data;
      this.dispatchEvent(new WorkboxEvent('message', {
        data: data,
        originalEvent: originalEvent
      }));
    };

    _createClass(Workbox, [{
      key: "active",
      get: function get() {
        return this._activeDeferred.promise;
      }
      /**
       * Resolves to the service worker registered by this instance as soon as it
       * is controlling the page. If a service worker was already controlling at
       * registration time then it will resolve to that if the script URLs (and
       * optionally script versions) match, otherwise it will wait until an update
       * is found and starts controlling the page.
       * Note: the first time a service worker is installed it will active but
       * not start controlling the page unless `clients.claim()` is called in the
       * service worker.
       *
       * @return {Promise<ServiceWorker>}
       */

    }, {
      key: "controlling",
      get: function get() {
        return this._controllingDeferred.promise;
      }
    }]);

    return Workbox;
  }(EventTargetShim); // The jsdoc comments below outline the events this instance may dispatch:

  /*
    Copyright 2019 Google LLC

    Use of this source code is governed by an MIT-style
    license that can be found in the LICENSE file or at
    https://opensource.org/licenses/MIT.
  */

  exports.Workbox = Workbox;
  exports.messageSW = messageSW;

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

}));