Source: client/subscribing-client.js

  1. /*
  2.  * Copyright 2023, TeamDev. All rights reserved.
  3.  *
  4.  * Licensed under the Apache License, Version 2.0 (the "License");
  5.  * you may not use this file except in compliance with the License.
  6.  * You may obtain a copy of the License at
  7.  *
  8.  * http://www.apache.org/licenses/LICENSE-2.0
  9.  *
  10.  * Redistribution and use in source and/or binary forms, with or without
  11.  * modification, must retain the above copyright notice and the following
  12.  * disclaimer.
  13.  *
  14.  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  15.  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  16.  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  17.  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  18.  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  19.  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  20.  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24.  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25.  */
  27. import {EventSubscriptionRequest, SubscriptionRequest} from "./subscribing-request";
  29. /**
  30.  * A client which manages entity state and event subscriptions.
  31.  *
  32.  * @abstract
  33.  */
  34. export class SubscribingClient {
  36.   /**
  37.    * @param {!ActorRequestFactory} actorRequestFactory
  38.    *        a request factory to build requests to Spine server
  39.    */
  40.   constructor(actorRequestFactory) {
  41.     this._requestFactory = actorRequestFactory;
  42.   }
  44.   /**
  45.    * Creates a new subscription request.
  46.    *
  47.    * @param {!Class<Message>} type the target entity type
  48.    * @param {!Client} client the client that initiated the request
  49.    * @return {SubscriptionRequest} a new subscription request
  50.    */
  51.   subscribeTo(type, client) {
  52.     return new SubscriptionRequest(type, client, this._requestFactory);
  53.   }
  55.   /**
  56.    * Subscribes to a given topic which targets an entity type.
  57.    *
  58.    * @param {!spine.client.Topic} topic a topic to subscribe to
  59.    * @return {Promise<EntitySubscriptionObject<Message>>} a subscription object
  60.    *
  61.    * @template <T> a Protobuf type of entities being the target of a subscription
  62.    */
  63.   subscribe(topic) {
  64.     throw new Error('Not implemented in abstract base.');
  65.   }
  67.   /**
  68.    * Creates a new event subscription request.
  69.    *
  70.    * @param {!Class<Message>} type the target event type
  71.    * @param {!Client} client the client that initiated the request
  72.    * @return {EventSubscriptionRequest} a new event subscription request
  73.    */
  74.   subscribeToEvent(type, client) {
  75.     return new EventSubscriptionRequest(type, client, this._requestFactory);
  76.   }
  78.   /**
  79.    * Subscribes to the given topic which targets an event type.
  80.    *
  81.    * @param {!spine.client.Topic} topic a topic to subscribe to
  82.    * @return {Promise<EventSubscriptionObject>} a subscription object
  83.    */
  84.   subscribeToEvents(topic) {
  85.     throw new Error('Not implemented in abstract base.');
  86.   }
  88.   /**
  89.    * Cancels all subscriptions, which were created through this instance of subscribing client.
  90.    */
  91.   cancelAllSubscriptions() {
  92.     throw new Error('Not implemented in abstract base.');
  93.   }
  95.   /**
  96.    * Returns a new topic factory instance which can be further used for the `Topic` creation.
  97.    *
  98.    * @return {TopicFactory}
  99.    */
  100.   newTopic() {
  101.     return this._requestFactory.topic();
  102.   }
  103. }
  105. const SUBSCRIPTIONS_NOT_SUPPORTED = 'Subscriptions are not supported.';
  107. /**
  108.  * A {@link SubscribingClient} which does not create subscriptions.
  109.  */
  110. export class NoOpSubscribingClient extends SubscribingClient {
  112.   constructor(actorRequestFactory) {
  113.     super(actorRequestFactory)
  114.   }
  116.   /**
  117.    * Always throws an error.
  118.    *
  119.    * @override
  120.    */
  121.   subscribe(topic) {
  122.     throw new Error(SUBSCRIPTIONS_NOT_SUPPORTED);
  123.   }
  125.   /**
  126.    * Always throws an error.
  127.    *
  128.    * @override
  129.    */
  130.   subscribeToEvents(topic) {
  131.     throw new Error(SUBSCRIPTIONS_NOT_SUPPORTED);
  132.   }
  134.   /**
  135.    * Always throws an error.
  136.    *
  137.    * @override
  138.    */
  139.   cancelAllSubscriptions() {
  140.     throw new Error(SUBSCRIPTIONS_NOT_SUPPORTED);
  141.   }
  142. }