Adds destroy method to the document loading task.

Also renames PDFPageProxy.destroy method to cleanup.

src/display/api.js

@@ -265,6 +265,9 @@ PDFJS.getDocument = function getDocument(src,
       pdfDataRangeTransport = Object.create(pdfDataRangeTransport);
       pdfDataRangeTransport.length = src.length;
       pdfDataRangeTransport.initialData = src.initialData;
+      if (!pdfDataRangeTransport.abort) {
+        pdfDataRangeTransport.abort = function () {};
+      }
     }
     src = Object.create(src);
     src.range = pdfDataRangeTransport;
@@ -324,6 +327,7 @@ PDFJS.getDocument = function getDocument(src,
   workerInitializedCapability.promise.then(function transportInitialized() {
     transport.fetchDocument(task, params);
   });
+  task._transport = transport;
 
   return task;
 };
@@ -336,6 +340,7 @@ var PDFDocumentLoadingTask = (function PDFDocumentLoadingTaskClosure() {
   /** @constructs PDFDocumentLoadingTask */
   function PDFDocumentLoadingTask() {
     this._capability = createPromiseCapability();
+    this._transport = null;
 
     /**
      * Callback to request a password if wrong or no password was provided.
@@ -361,7 +366,14 @@ var PDFDocumentLoadingTask = (function PDFDocumentLoadingTaskClosure() {
       return this._capability.promise;
     },
 
-    // TODO add cancel or abort method
+    /**
+     * Aborts all network requests and destroys worker.
+     * @return {Promise} A promise that is resolved after destruction activity
+     *                   is completed.
+     */
+    destroy: function () {
+      return this._transport.destroy();
+    },
 
     /**
      * Registers callbacks to indicate the document loading completion.
@@ -448,6 +460,9 @@ var PDFDataRangeTransport = (function pdfDataRangeTransportClosure() {
     requestDataRange:
         function PDFDataRangeTransport_requestDataRange(begin, end) {
       throw new Error('Abstract method PDFDataRangeTransport.requestDataRange');
+    },
+
+    abort: function PDFDataRangeTransport_abort() {
     }
   };
   return PDFDataRangeTransport;
@@ -461,9 +476,10 @@ PDFJS.PDFDataRangeTransport = PDFDataRangeTransport;
  * @class
  */
 var PDFDocumentProxy = (function PDFDocumentProxyClosure() {
-  function PDFDocumentProxy(pdfInfo, transport) {
+  function PDFDocumentProxy(pdfInfo, transport, loadingTask) {
     this.pdfInfo = pdfInfo;
     this.transport = transport;
+    this.loadingTask = loadingTask;
   }
   PDFDocumentProxy.prototype = /** @lends PDFDocumentProxy.prototype */ {
     /**
@@ -586,7 +602,7 @@ var PDFDocumentProxy = (function PDFDocumentProxyClosure() {
      * Destroys current document instance and terminates worker.
      */
     destroy: function PDFDocumentProxy_destroy() {
-      this.transport.destroy();
+      return this.transport.destroy();
     }
   };
   return PDFDocumentProxy;
@@ -663,8 +679,9 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
     this.commonObjs = transport.commonObjs;
     this.objs = new PDFObjects();
     this.cleanupAfterRender = false;
-    this.pendingDestroy = false;
+    this.pendingCleanup = false;
     this.intentStates = {};
+    this.destroyed = false;
   }
   PDFPageProxy.prototype = /** @lends PDFPageProxy.prototype */ {
     /**
@@ -728,7 +745,7 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
 
       // If there was a pending destroy cancel it so no cleanup happens during
       // this call to render.
-      this.pendingDestroy = false;
+      this.pendingCleanup = false;
 
       var renderingIntent = (params.intent === 'print' ? 'print' : 'display');
 
@@ -775,7 +792,7 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
       var self = this;
       intentState.displayReadyCapability.promise.then(
         function pageDisplayReadyPromise(transparency) {
-          if (self.pendingDestroy) {
+          if (self.pendingCleanup) {
             complete();
             return;
           }
@@ -795,9 +812,9 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
         }
 
         if (self.cleanupAfterRender) {
-          self.pendingDestroy = true;
+          self.pendingCleanup = true;
         }
-        self._tryDestroy();
+        self._tryCleanup();
 
         if (error) {
           internalRenderTask.capability.reject(error);
@@ -858,20 +875,47 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
         pageIndex: this.pageNumber - 1
       });
     },
+
     /**
-     * Destroys resources allocated by the page.
+     * Destroys page object.
      */
-    destroy: function PDFPageProxy_destroy() {
-      this.pendingDestroy = true;
-      this._tryDestroy();
+    _destroy: function PDFPageProxy_destroy() {
+      this.destroyed = true;
+      this.transport.pageCache[this.pageIndex] = null;
+
+      Object.keys(this.intentStates).forEach(function(intent) {
+        var intentState = this.intentStates[intent];
+        intentState.renderTasks.forEach(function(renderTask) {
+          renderTask.cancel();
+        });
+      }, this);
+      this.objs.clear();
+      this.annotationsPromise = null;
+      this.pendingCleanup = false;
+    },
+
+    /**
+     * Cleans up resources allocated by the page.
+     * Deprecated, use cleanup() instead.
+     */
+    destroy: function() {
+      this.cleanup();
+    },
+
+    /**
+     * Cleans up resources allocated by the page.
+     */
+    cleanup: function PDFPageProxy_cleanup() {
+      this.pendingCleanup = true;
+      this._tryCleanup();
     },
     /**
      * For internal use only. Attempts to clean up if rendering is in a state
      * where that's possible.
      * @ignore
      */
-    _tryDestroy: function PDFPageProxy__destroy() {
-      if (!this.pendingDestroy ||
+    _tryCleanup: function PDFPageProxy_tryCleanup() {
+      if (!this.pendingCleanup ||
           Object.keys(this.intentStates).some(function(intent) {
             var intentState = this.intentStates[intent];
             return (intentState.renderTasks.length !== 0 ||
@@ -885,7 +929,7 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
       }, this);
       this.objs.clear();
       this.annotationsPromise = null;
-      this.pendingDestroy = false;
+      this.pendingCleanup = false;
     },
     /**
      * For internal use only.
@@ -923,7 +967,7 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
 
       if (operatorListChunk.lastChunk) {
         intentState.receivingOperatorList = false;
-        this._tryDestroy();
+        this._tryCleanup();
       }
     }
   };
@@ -941,6 +985,8 @@ var WorkerTransport = (function WorkerTransportClosure() {
     this.commonObjs = new PDFObjects();
 
     this.loadingTask = null;
+    this.destroyed = false;
+    this.destroyCapability = null;
 
     this.pageCache = [];
     this.pagePromises = [];
@@ -1001,6 +1047,18 @@ var WorkerTransport = (function WorkerTransportClosure() {
   }
   WorkerTransport.prototype = {
     destroy: function WorkerTransport_destroy() {
+      if (this.destroyCapability) {
+        return this.destroyCapability.promise;
+      }
+
+      this.destroyed = true;
+      this.destroyCapability = createPromiseCapability();
+
+      this.pageCache.forEach(function (page) {
+        if (page) {
+          page._destroy();
+        }
+      });
       this.pageCache = [];
       this.pagePromises = [];
       var self = this;
@@ -1009,7 +1067,14 @@ var WorkerTransport = (function WorkerTransportClosure() {
         if (self.worker) {
           self.worker.terminate();
         }
-      });
+        if (self.pdfDataRangeTransport) {
+          self.pdfDataRangeTransport.abort();
+          self.pdfDataRangeTransport = null;
+        }
+        self.messageHandler = null;
+        self.destroyCapability.resolve();
+      }, this.destroyCapability.reject);
+      return this.destroyCapability.promise;
     },
 
     setupFakeWorker: function WorkerTransport_setupFakeWorker() {
@@ -1091,9 +1156,10 @@ var WorkerTransport = (function WorkerTransportClosure() {
       messageHandler.on('GetDoc', function transportDoc(data) {
         var pdfInfo = data.pdfInfo;
         this.numPages = data.pdfInfo.numPages;
-        var pdfDocument = new PDFDocumentProxy(pdfInfo, this);
+        var loadingTask = this.loadingTask;
+        var pdfDocument = new PDFDocumentProxy(pdfInfo, this, loadingTask);
         this.pdfDocument = pdfDocument;
-        this.loadingTask._capability.resolve(pdfDocument);
+        loadingTask._capability.resolve(pdfDocument);
       }, this);
 
       messageHandler.on('NeedPassword',
@@ -1294,6 +1360,12 @@ var WorkerTransport = (function WorkerTransportClosure() {
     },
 
     fetchDocument: function WorkerTransport_fetchDocument(loadingTask, source) {
+      if (this.destroyed) {
+        loadingTask._capability.reject(new Error('Loading aborted'));
+        this.destroyCapability.resolve();
+        return;
+      }
+
       this.loadingTask = loadingTask;
 
       source.disableAutoFetch = PDFJS.disableAutoFetch;
@@ -1332,6 +1404,9 @@ var WorkerTransport = (function WorkerTransportClosure() {
       var promise = this.messageHandler.sendWithPromise('GetPage', {
         pageIndex: pageIndex
       }).then(function (pageInfo) {
+        if (this.destroyed) {
+          throw new Error('Transport destroyed');
+        }
         var page = new PDFPageProxy(pageIndex, pageInfo, this);
         this.pageCache[pageIndex] = page;
         return page;
@@ -1389,7 +1464,7 @@ var WorkerTransport = (function WorkerTransportClosure() {
         for (var i = 0, ii = this.pageCache.length; i < ii; i++) {
           var page = this.pageCache[i];
           if (page) {
-            page.destroy();
+            page.cleanup();
           }
         }
         this.commonObjs.clear();