feat(Offline): Allow no timeout when opening IndexedDB database (#8372)

This is the followup to the previous PR #8366 , to allow to disable the
timeout, as per @avelad
[suggestion](#8366 (comment))
to add this in another PR...

---------

Co-authored-by: Loïc Raux <[email protected]>
Co-authored-by: Álvaro Velad Galván <[email protected]>
Co-authored-by: Wojciech Tyczyński <[email protected]>

Author: 4 people

docs/tutorials/offline.md

@@ -685,11 +685,29 @@ setting or set it explicitly with:
 usePersistentLicense: true
 ```
 
-## Configure opening IndexedDB timeout
+## Configure the timeout for opening IndexedDB-based storage
 
-This configuration must be done before doing any other operation:
+There is a default timeout of 5 seconds for opening IndexedDB-based storage.
+This is useful to ensure that your application does not block indefinitely
+while waiting for the IndexedDB database to open.
+
+If you want to change the value of this timeout, you can do so by setting
+accordingly the value of the `shaka.offline.indexeddb.StorageMechanismOpenTimeout`
+variable. For example, to set the timeout to 10 seconds, you can do the following:
 
 ```js
 // In seconds
-shaka.offline.indexeddb.StorageMechanismOpenTimeout = 5;
+shaka.offline.indexeddb.StorageMechanismOpenTimeout = 10;
+```
+
+You can also disable this timeout and consequently wait indefinitely for the
+IndexedDB database to open successfully or fail to open. To do this, set the
+`shaka.offline.indexeddb.StorageMechanismOpenTimeout` variable to `false`:
+
+```js
+shaka.offline.indexeddb.StorageMechanismOpenTimeout = false;
 ```
+
+Note that this configuration must be done before doing any other offline
+storage related operation (download and store content, list content,
+remove content, playback of content).

lib/offline/indexeddb/storage_mechanism.js

@@ -67,14 +67,18 @@ shaka.offline.indexeddb.StorageMechanism = class {
           shaka.util.Error.Category.STORAGE,
           shaka.util.Error.Code.INDEXED_DB_INIT_TIMED_OUT));
     });
-    timeOutTimer.tickAfter(shaka.offline.indexeddb.StorageMechanismOpenTimeout);
+    const openTimeout = shaka.offline.indexeddb.StorageMechanismOpenTimeout;
+    if (typeof openTimeout === 'number' && openTimeout > 0) {
+      timeOutTimer.tickAfter(openTimeout);
+    }
 
     const open = window.indexedDB.open(name, version);
     open.onsuccess = (event) => {
       if (timedOut) {
         // Too late, we have already given up on opening the storage mechanism.
         return;
       }
+      timeOutTimer.stop();
       const db = open.result;
       this.db_ = db;
       this.v1_ = shaka.offline.indexeddb.StorageMechanism.createV1_(db);
@@ -86,7 +90,6 @@ shaka.offline.indexeddb.StorageMechanism = class {
       this.v5_ = shaka.offline.indexeddb.StorageMechanism.createV5_(db);
       this.sessions_ =
           shaka.offline.indexeddb.StorageMechanism.createEmeSessionCell_(db);
-      timeOutTimer.stop();
       p.resolve();
     };
     open.onupgradeneeded = (event) => {
@@ -98,12 +101,12 @@ shaka.offline.indexeddb.StorageMechanism = class {
         // Too late, we have already given up on opening the storage mechanism.
         return;
       }
+      timeOutTimer.stop();
       p.reject(new shaka.util.Error(
           shaka.util.Error.Severity.CRITICAL,
           shaka.util.Error.Category.STORAGE,
           shaka.util.Error.Code.INDEXED_DB_ERROR,
           open.error));
-      timeOutTimer.stop();
 
       // Firefox will raise an error on the main thread unless we stop it here.
       event.preventDefault();
@@ -383,7 +386,10 @@ shaka.offline.indexeddb.StorageMechanism.V5_MANIFEST_STORE = 'manifest-v5';
 shaka.offline.indexeddb.StorageMechanism.SESSION_ID_STORE = 'session-ids';
 
 /**
- * @type {number}
+ * Timeout in seconds for opening the IndexedDB database,
+ * or <code>false</code> to disable the timeout and wait indefinitely
+ * for the database to open successfully or fail.
+ * @type {number|boolean}
  * @export
  */
 shaka.offline.indexeddb.StorageMechanismOpenTimeout = 5;