Source: lib/offline/indexeddb/db_connection.js

  1. /*! @license
  2.  * Shaka Player
  3.  * Copyright 2016 Google LLC
  4.  * SPDX-License-Identifier: Apache-2.0
  5.  */
  7. goog.provide('shaka.offline.indexeddb.DBConnection');
  9. goog.require('shaka.offline.indexeddb.DBOperation');
  10. goog.require('shaka.util.ArrayUtils');
  13. /**
  14.  * DBConnection is used to manage an IndexedDB connection. It can create new
  15.  * operations. If the connection is killed (via |destroy|) all pending
  16.  * operations will be cancelled.
  17.  */
  18. shaka.offline.indexeddb.DBConnection = class {
  19.   /**
  20.    * @param {IDBDatabase} connection A connection to an IndexedDB instance.
  21.    */
  22.   constructor(connection) {
  23.     /** @private {IDBDatabase} */
  24.     this.connection_ = connection;
  25.     /** @private {!Array.<shaka.offline.indexeddb.DBOperation>} */
  26.     this.pending_ = [];
  27.   }
  29.   /**
  30.    * @return {!Promise}
  31.    */
  32.   destroy() {
  33.     return Promise.all(this.pending_.map((op) => {
  34.       return op.abort();
  35.     }));
  36.   }
  38.   /**
  39.    * @param {string} store The name of the store that the operation should
  40.    *                       occur on.
  41.    * @return {!shaka.offline.indexeddb.DBOperation}
  42.    */
  43.   startReadOnlyOperation(store) {
  44.     return this.startOperation_(store, 'readonly');
  45.   }
  47.   /**
  48.    * @param {string} store The name of the store that the operation should
  49.    *                       occur on.
  50.    * @return {!shaka.offline.indexeddb.DBOperation}
  51.    */
  52.   startReadWriteOperation(store) {
  53.     return this.startOperation_(store, 'readwrite');
  54.   }
  56.   /**
  57.    * @param {string} store The name of the store that the operation should
  58.    *                       occur on.
  59.    * @param {string} type The type of operation being performed on the store.
  60.    *                      This determines what commands may be performed. This
  61.    *                      can either be "readonly" or "readwrite".
  62.    * @return {!shaka.offline.indexeddb.DBOperation}
  63.    * @private
  64.    */
  65.   startOperation_(store, type) {
  66.     const transaction = this.connection_.transaction([store], type);
  67.     const operation =
  68.         new shaka.offline.indexeddb.DBOperation(transaction, store);
  70.     this.pending_.push(operation);
  72.     // Once the operation is done (regardless of outcome) stop tracking it.
  73.     operation.promise().then(
  74.         () => this.stopTracking_(operation),
  75.         () => this.stopTracking_(operation));
  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. };