Theory 3: blocked operations

Author: joeyparrish

externs/idb.js

@@ -23,3 +23,6 @@ var IDBOpenDBRequest = function() {};
 
 /** @type {!IDBDatabase} */
 IDBOpenDBRequest.prototype.result;
+
+/** @type {function(!Event)} */
+IDBOpenDBRequest.prototype.onversionchange;

lib/offline/indexeddb/db_operation.js

@@ -33,6 +33,7 @@ shaka.offline.indexeddb.DBOperation = class {
       this.promise_.reject();
     };
     transaction.onerror = (event) => {
+      window.dump('Transaction error');
       this.promise_.reject();
     };
     transaction.oncomplete = (event) => {
@@ -68,7 +69,10 @@ shaka.offline.indexeddb.DBOperation = class {
   forEachEntry(callback) {
     return new Promise((resolve, reject) => {
       const req = this.store_.openCursor();
-      req.onerror = reject;
+      req.onerror = (event) => {
+        window.dump('Cursor error');
+        reject(event);
+      };
       req.onsuccess = async (event) => {
         // When we reach the end of the data that the cursor is iterating over,
         // |req.result| will be null to signal the end of the iteration.

lib/offline/indexeddb/storage_mechanism.js

@@ -46,6 +46,13 @@ shaka.offline.indexeddb.StorageMechanism = class {
     this.v5_ = null;
     /** @private {shaka.extern.EmeSessionStorageCell} */
     this.sessions_ = null;
+    /** @private {string} */
+    this.stack_ = '';
+    try {
+      throw new Error('');
+    } catch (error) {
+      this.stack_ = error.stack;
+    }
   }
 
   /**
@@ -62,6 +69,7 @@ shaka.offline.indexeddb.StorageMechanism = class {
     let timedOut = false;
     const timeOutTimer = new shaka.util.Timer(() => {
       timedOut = true;
+      window.dump('TIMEOUT on open from: ' + this.stack_);
       p.reject(new shaka.util.Error(
           shaka.util.Error.Severity.CRITICAL,
           shaka.util.Error.Category.STORAGE,
@@ -89,6 +97,9 @@ shaka.offline.indexeddb.StorageMechanism = class {
       timeOutTimer.stop();
       p.resolve();
     };
+    open.onversionchange = (event) => {
+      window.dump('VERSIONCHANGE triggered for database from: ' + this.stack_);
+    };
     open.onupgradeneeded = (event) => {
       // Add object stores for the latest version only.
       this.createStores_(open.result);
@@ -105,6 +116,10 @@ shaka.offline.indexeddb.StorageMechanism = class {
           open.error));
       timeOutTimer.stop();
     };
+    open.onblocked = (event) => {
+      window.dump('Opening ' + name + ' is being blocked from: ' + this.stack_);
+      p.reject(new Error('Open blocked'));
+    };
 
     return p;
   }
@@ -191,7 +206,7 @@ shaka.offline.indexeddb.StorageMechanism = class {
       this.db_.close();
     }
 
-    await shaka.offline.indexeddb.StorageMechanism.deleteAll_();
+    await this.deleteAll_();
 
     // Reset before initializing.
     this.db_ = null;
@@ -329,14 +344,16 @@ shaka.offline.indexeddb.StorageMechanism = class {
    * @return {!Promise}
    * @private
    */
-  static deleteAll_() {
+  deleteAll_() {
     const name = shaka.offline.indexeddb.StorageMechanism.DB_NAME;
 
     const p = new shaka.util.PublicPromise();
 
     const del = window.indexedDB.deleteDatabase(name);
     del.onblocked = (event) => {
-      shaka.log.warning('Deleting', name, 'is being blocked', event);
+      window.dump(
+          'Deleting ' + name + ' is being blocked from: ' + this.stack_);
+      p.reject(new Error('Delete blocked'));
     };
     del.onsuccess = (event) => {
       p.resolve();

test/test/util/canned_idb.js

@@ -160,9 +160,21 @@ shaka.test.CannedIDB = class {
    * @private
    */
   static openDatabase_(name) {
+    let stack;
+    try {
+      throw new Error('');
+    } catch (error) {  // eslint-disable-line
+      stack = error.stack;
+    }
+
     return new Promise((resolve, reject) => {
       const request = indexedDB.open(name);
 
+      request.onversionchange = (event) => {
+        window.dump(
+            'VERSIONCHANGE from openDatabase_ in canned_idb from ' + stack);
+      };
+
       request.onupgradeneeded = (event) => {
         reject(new Error('DB did not exist!'));
         const transaction = event.target.transaction;
@@ -253,9 +265,21 @@ shaka.test.CannedIDB = class {
    * @private
    */
   static createDatabase_(name, savedDatabase) {
+    let stack;
+    try {
+      throw new Error('');
+    } catch (error) {  // eslint-disable-line
+      stack = error.stack;
+    }
+
     return new Promise((resolve, reject) => {
       const request = indexedDB.open(name, savedDatabase.version);
 
+      request.onversionchange = (event) => {
+        window.dump(
+            'VERSIONCHANGE from createDatabase_ in canned_idb from ' + stack);
+      };
+
       request.onupgradeneeded = (event) => {
         shaka.log.debug('DB upgrade from', event.oldVersion, 'to',
             savedDatabase.version);

test/test/util/indexeddb_utils.js

@@ -77,7 +77,17 @@ shaka.test.IndexedDBUtils = class {
     /** @type {!shaka.util.PublicPromise} */
     const p = new shaka.util.PublicPromise();
 
+    let stack;
+    try {
+      throw new Error('');
+    } catch (error) {  // eslint-disable-line
+      stack = error.stack;
+    }
+
     const open = window.indexedDB.open(name, version);
+    open.onversionchange = (event) => {
+      window.dump('VERSIONCHANGE from dbOpenNew_ in idb_utils from ' + stack);
+    };
     open.onerror = (e) => {
       p.reject();
     };
@@ -111,7 +121,17 @@ shaka.test.IndexedDBUtils = class {
     /** @type {!shaka.util.PublicPromise} */
     const p = new shaka.util.PublicPromise();
 
+    let stack;
+    try {
+      throw new Error('');
+    } catch (error) {  // eslint-disable-line
+      stack = error.stack;
+    }
+
     const open = window.indexedDB.open(name);
+    open.onversionchange = (event) => {
+      window.dump('VERSIONCHANGE from open in idb_utils from ' + stack);
+    };
     open.onerror = (e) => {
       p.reject();
     };