Source: lib/offline/indexeddb/db_connection.js

  1. /** @license
  2.  * Copyright 2016 Google LLC
  3.  * SPDX-License-Identifier: Apache-2.0
  4.  */
  6. goog.provide('shaka.offline.indexeddb.DBConnection');
  8. goog.require('shaka.offline.indexeddb.DBOperation');
  9. goog.require('shaka.util.ArrayUtils');
  12. /**
  13.  * DBConnection is used to manage an IndexedDB connection. It can create new
  14.  * operations. If the connection is killed (via |destroy|) all pending
  15.  * operations will be cancelled.
  16.  */
  17. shaka.offline.indexeddb.DBConnection = class {
  18.   /**
  19.    * @param {IDBDatabase} connection A connection to an IndexedDB instance.
  20.    */
  21.   constructor(connection) {
  22.     /** @private {IDBDatabase} */
  23.     this.connection_ = connection;
  24.     /** @private {!Array.<shaka.offline.indexeddb.DBOperation>} */
  25.     this.pending_ = [];
  26.   }
  28.   /**
  29.    * @return {!Promise}
  30.    */
  31.   destroy() {
  32.     return Promise.all(this.pending_.map((op) => {
  33.       return op.abort();
  34.     }));
  35.   }
  37.   /**
  38.    * @param {string} store The name of the store that the operation should
  39.    *                       occur on.
  40.    * @return {!shaka.offline.indexeddb.DBOperation}
  41.    */
  42.   startReadOnlyOperation(store) {
  43.     return this.startOperation_(store, 'readonly');
  44.   }
  46.   /**
  47.    * @param {string} store The name of the store that the operation should
  48.    *                       occur on.
  49.    * @return {!shaka.offline.indexeddb.DBOperation}
  50.    */
  51.   startReadWriteOperation(store) {
  52.     return this.startOperation_(store, 'readwrite');
  53.   }
  55.   /**
  56.    * @param {string} store The name of the store that the operation should
  57.    *                       occur on.
  58.    * @param {string} type The type of operation being performed on the store.
  59.    *                      This determines what commands may be performed. This
  60.    *                      can either be "readonly" or "readwrite".
  61.    * @return {!shaka.offline.indexeddb.DBOperation}
  62.    * @private
  63.    */
  64.   startOperation_(store, type) {
  65.     const transaction = this.connection_.transaction([store], type);
  66.     const operation =
  67.         new shaka.offline.indexeddb.DBOperation(transaction, store);
  69.     this.pending_.push(operation);
  71.     // Once the operation is done (regardless of outcome) stop tracking it.
  72.     operation.promise().then(
  73.         () => this.stopTracking_(operation),
  74.         () => this.stopTracking_(operation)
  75.     );
  77.     return operation;
  78.   }
  80.   /**
  81.    * @param {!shaka.offline.indexeddb.DBOperation} operation
  82.    * @private
  83.    */
  84.   stopTracking_(operation) {
  85.     shaka.util.ArrayUtils.remove(this.pending_, operation);
  86.   }
  87. };