Refactors MessageHandler.send to remove callbacks

src/core/evaluator.js

@@ -214,7 +214,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
         then(function(imageObj) {
           var imgData = imageObj.createImageData(/* forceRGBA = */ false);
           self.handler.send('obj', [objId, self.pageIndex, 'Image', imgData],
-            null, [imgData.data.buffer]);
+            [imgData.data.buffer]);
         }).then(null, function (reason) {
           warn('Unable to decode image: ' + reason);
           self.handler.send('obj', [objId, self.pageIndex, 'Image', null]);
@@ -1592,7 +1592,7 @@ var OperatorList = (function OperatorListClosure() {
         },
         pageIndex: this.pageIndex,
         intent: this.intent
-      }, null, transfers);
+      }, transfers);
       this.dependencies = {};
       this.fnArray.length = 0;
       this.argsArray.length = 0;

src/core/image.js

@@ -31,14 +31,11 @@ var PDFImage = (function PDFImageClosure() {
       var colorSpace = dict.get('ColorSpace', 'CS');
       colorSpace = ColorSpace.parse(colorSpace, xref, res);
       var numComps = colorSpace.numComps;
-      var resolvePromise;
+      var decodePromise = handler.sendWithPromise('JpegDecode',
-      handler.send('JpegDecode', [image.getIR(), numComps], function(message) {
+                                                  [image.getIR(), numComps]);
+      return decodePromise.then(function (message) {
         var data = message.data;
-        var stream = new Stream(data, 0, data.length, image.dict);
+        return new Stream(data, 0, data.length, image.dict);
-        resolvePromise(stream);
-      });
-      return new Promise(function (resolve) {
-        resolvePromise = resolve;
       });
     } else {
       return Promise.resolve(image);

src/core/worker.js

@@ -279,60 +279,47 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
       });
     });
 
-    handler.on('GetPageIndex', function wphSetupGetPageIndex(data, deferred) {
+    handler.on('GetPageIndex', function wphSetupGetPageIndex(data) {
       var ref = new Ref(data.ref.num, data.ref.gen);
       var catalog = pdfManager.pdfDocument.catalog;
-      catalog.getPageIndex(ref).then(function (pageIndex) {
+      return catalog.getPageIndex(ref);
-        deferred.resolve(pageIndex);
-      }, deferred.reject);
     });
 
     handler.on('GetDestinations',
-      function wphSetupGetDestinations(data, deferred) {
+      function wphSetupGetDestinations(data) {
-        pdfManager.ensureCatalog('destinations').then(function(destinations) {
+        return pdfManager.ensureCatalog('destinations');
-          deferred.resolve(destinations);
-        });
       }
     );
 
     handler.on('GetAttachments',
-      function wphSetupGetAttachments(data, deferred) {
+      function wphSetupGetAttachments(data) {
-        pdfManager.ensureCatalog('attachments').then(function(attachments) {
+        return pdfManager.ensureCatalog('attachments');
-          deferred.resolve(attachments);
-        }, deferred.reject);
       }
     );
 
     handler.on('GetJavaScript',
-      function wphSetupGetJavaScript(data, deferred) {
+      function wphSetupGetJavaScript(data) {
-        pdfManager.ensureCatalog('javaScript').then(function (js) {
+        return pdfManager.ensureCatalog('javaScript');
-          deferred.resolve(js);
-        }, deferred.reject);
       }
     );
 
     handler.on('GetOutline',
-      function wphSetupGetOutline(data, deferred) {
+      function wphSetupGetOutline(data) {
-        pdfManager.ensureCatalog('documentOutline').then(function (outline) {
+        return pdfManager.ensureCatalog('documentOutline');
-          deferred.resolve(outline);
-        }, deferred.reject);
       }
     );
 
     handler.on('GetMetadata',
-      function wphSetupGetMetadata(data, deferred) {
+      function wphSetupGetMetadata(data) {
-        Promise.all([pdfManager.ensureDoc('documentInfo'),
+        return Promise.all([pdfManager.ensureDoc('documentInfo'),
-                     pdfManager.ensureCatalog('metadata')]).then(
+                            pdfManager.ensureCatalog('metadata')]);
-            function (results) {
-          deferred.resolve(results);
-        }, deferred.reject);
       }
     );
 
-    handler.on('GetData', function wphSetupGetData(data, deferred) {
+    handler.on('GetData', function wphSetupGetData(data) {
       pdfManager.requestLoadedStream();
-      pdfManager.onLoadedStream().then(function(stream) {
+      return pdfManager.onLoadedStream().then(function(stream) {
-        deferred.resolve(stream.bytes);
+        return stream.bytes;
       });
     });
 
@@ -398,29 +385,25 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
       });
     }, this);
 
-    handler.on('GetTextContent', function wphExtractText(data, deferred) {
+    handler.on('GetTextContent', function wphExtractText(data) {
-      pdfManager.getPage(data.pageIndex).then(function(page) {
+      return pdfManager.getPage(data.pageIndex).then(function(page) {
         var pageNum = data.pageIndex + 1;
         var start = Date.now();
-        page.extractTextContent().then(function(textContent) {
+        return page.extractTextContent().then(function(textContent) {
-          deferred.resolve(textContent);
           info('text indexing: page=' + pageNum + ' - time=' +
                (Date.now() - start) + 'ms');
-        }, function (e) {
+          return textContent;
-          // Skip errored pages
-          deferred.reject(e);
         });
       });
     });
 
-    handler.on('Cleanup', function wphCleanup(data, deferred) {
+    handler.on('Cleanup', function wphCleanup(data) {
       pdfManager.cleanup();
-      deferred.resolve(true);
+      return true;
     });
 
-    handler.on('Terminate', function wphTerminate(data, deferred) {
+    handler.on('Terminate', function wphTerminate(data) {
       pdfManager.terminate();
-      deferred.resolve();
     });
   }
 };

src/display/api.js

@@ -546,15 +546,9 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
      * object that represent the page text content.
      */
     getTextContent: function PDFPageProxy_getTextContent() {
-      return new Promise(function (resolve) {
+      return this.transport.messageHandler.sendWithPromise('GetTextContent', {
-        this.transport.messageHandler.send('GetTextContent', {
+        pageIndex: this.pageNumber - 1
-            pageIndex: this.pageNumber - 1
+      });
-          },
-          function textContentCallback(textContent) {
-            resolve(textContent);
-          }
-        );
-      }.bind(this));
     },
     /**
      * Destroys resources allocated by the page.
@@ -682,7 +676,7 @@ var WorkerTransport = (function WorkerTransportClosure() {
         // Some versions of Opera throw a DATA_CLONE_ERR on serializing the
         // typed array. Also, checking if we can use transfers.
         try {
-          messageHandler.send('test', testObj, null, [testObj.buffer]);
+          messageHandler.send('test', testObj, [testObj.buffer]);
         } catch (ex) {
           info('Cannot use postMessage transfers');
           testObj[0] = 0;
@@ -707,7 +701,7 @@ var WorkerTransport = (function WorkerTransportClosure() {
       this.pageCache = [];
       this.pageCapabilities = [];
       var self = this;
-      this.messageHandler.send('Terminate', null, function () {
+      this.messageHandler.sendWithPromise('Terminate', null).then(function () {
         FontLoader.clear();
         if (self.worker) {
           self.worker.terminate();
@@ -934,9 +928,9 @@ var WorkerTransport = (function WorkerTransportClosure() {
         this.workerReadyCapability.reject(data);
       }, this);
 
-      messageHandler.on('PageError', function transportError(data, intent) {
+      messageHandler.on('PageError', function transportError(data) {
         var page = this.pageCache[data.pageNum - 1];
-        var intentState = page.intentStates[intent];
+        var intentState = page.intentStates[data.intent];
         if (intentState.displayReadyCapability.promise) {
           intentState.displayReadyCapability.reject(data.error);
         } else {
@@ -944,40 +938,47 @@ var WorkerTransport = (function WorkerTransportClosure() {
         }
       }, this);
 
-      messageHandler.on('JpegDecode', function(data, deferred) {
+      messageHandler.on('JpegDecode', function(data) {
         var imageUrl = data[0];
         var components = data[1];
         if (components != 3 && components != 1) {
-          error('Only 3 component or 1 component can be returned');
+          return Promise.reject(
+            new Error('Only 3 component or 1 component can be returned'));
         }
 
-        var img = new Image();
+        return new Promise(function (resolve, reject) {
-        img.onload = (function messageHandler_onloadClosure() {
+          var img = new Image();
-          var width = img.width;
+          img.onload = function () {
-          var height = img.height;
+            var width = img.width;
-          var size = width * height;
+            var height = img.height;
-          var rgbaLength = size * 4;
+            var size = width * height;
-          var buf = new Uint8Array(size * components);
+            var rgbaLength = size * 4;
-          var tmpCanvas = createScratchCanvas(width, height);
+            var buf = new Uint8Array(size * components);
-          var tmpCtx = tmpCanvas.getContext('2d');
+            var tmpCanvas = createScratchCanvas(width, height);
-          tmpCtx.drawImage(img, 0, 0);
+            var tmpCtx = tmpCanvas.getContext('2d');
-          var data = tmpCtx.getImageData(0, 0, width, height).data;
+            tmpCtx.drawImage(img, 0, 0);
-          var i, j;
+            var data = tmpCtx.getImageData(0, 0, width, height).data;
+            var i, j;
 
-          if (components == 3) {
+            if (components == 3) {
-            for (i = 0, j = 0; i < rgbaLength; i += 4, j += 3) {
+              for (i = 0, j = 0; i < rgbaLength; i += 4, j += 3) {
-              buf[j] = data[i];
+                buf[j] = data[i];
-              buf[j + 1] = data[i + 1];
+                buf[j + 1] = data[i + 1];
-              buf[j + 2] = data[i + 2];
+                buf[j + 2] = data[i + 2];
+              }
+            } else if (components == 1) {
+              for (i = 0, j = 0; i < rgbaLength; i += 4, j++) {
+                buf[j] = data[i];
+              }
             }
-          } else if (components == 1) {
+            resolve({ data: buf, width: width, height: height});
-            for (i = 0, j = 0; i < rgbaLength; i += 4, j++) {
+          };
-              buf[j] = data[i];
+          img.onerror = function () {
-            }
+            reject(new Error('JpegDecode failed to load image'));
-          }
+          };
-          deferred.resolve({ data: buf, width: width, height: height});
+          img.src = imageUrl;
-        }).bind(this);
+        });
-        img.src = imageUrl;
+
       });
     },
 
@@ -1019,13 +1020,7 @@ var WorkerTransport = (function WorkerTransportClosure() {
     },
 
     getPageIndex: function WorkerTransport_getPageIndexByRef(ref) {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetPageIndex', { ref: ref });
-        this.messageHandler.send('GetPageIndex', { ref: ref },
-          function (pageIndex) {
-            resolve(pageIndex);
-          }
-        );
-      }.bind(this));
     },
 
     getAnnotations: function WorkerTransport_getAnnotations(pageIndex) {
@@ -1034,71 +1029,43 @@ var WorkerTransport = (function WorkerTransportClosure() {
     },
 
     getDestinations: function WorkerTransport_getDestinations() {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetDestinations', null);
-        this.messageHandler.send('GetDestinations', null,
-          function transportDestinations(destinations) {
-            resolve(destinations);
-          }
-        );
-      }.bind(this));
     },
 
     getAttachments: function WorkerTransport_getAttachments() {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetAttachments', null);
-        this.messageHandler.send('GetAttachments', null,
-          function transportAttachments(attachments) {
-            resolve(attachments);
-          }
-        );
-      }.bind(this));
     },
 
     getJavaScript: function WorkerTransport_getJavaScript() {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetJavaScript', null);
-        this.messageHandler.send('GetJavaScript', null,
-          function transportJavaScript(js) {
-            resolve(js);
-          }
-        );
-      }.bind(this));
     },
 
     getOutline: function WorkerTransport_getOutline() {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetOutline', null);
-        this.messageHandler.send('GetOutline', null,
-          function transportOutline(outline) {
-            resolve(outline);
-          }
-        );
-      }.bind(this));
     },
 
     getMetadata: function WorkerTransport_getMetadata() {
-      return new Promise(function (resolve) {
+      return this.messageHandler.sendWithPromise('GetMetadata', null).
-        this.messageHandler.send('GetMetadata', null,
+        then(function transportMetadata(results) {
-          function transportMetadata(results) {
+        return {
-            resolve({
+          info: results[0],
-              info: results[0],
+          metadata: (results[1] ? new PDFJS.Metadata(results[1]) : null)
-              metadata: (results[1] ? new PDFJS.Metadata(results[1]) : null)
+        };
-            });
+      });
-          }
-        );
-      }.bind(this));
     },
 
     startCleanup: function WorkerTransport_startCleanup() {
-      this.messageHandler.send('Cleanup', null,
+      this.messageHandler.sendWithPromise('Cleanup', null).
-        function endCleanup() {
+        then(function endCleanup() {
-          for (var i = 0, ii = this.pageCache.length; i < ii; i++) {
+        for (var i = 0, ii = this.pageCache.length; i < ii; i++) {
-            var page = this.pageCache[i];
+          var page = this.pageCache[i];
-            if (page) {
+          if (page) {
-              page.destroy();
+            page.destroy();
-            }
           }
-          this.commonObjs.clear();
+        }
-          FontLoader.clear();
+        this.commonObjs.clear();
-        }.bind(this)
+        FontLoader.clear();
-      );
+      }.bind(this));
     }
   };
   return WorkerTransport;

src/shared/util.js

@@ -1366,7 +1366,7 @@ function MessageHandler(name, comObj) {
   this.comObj = comObj;
   this.callbackIndex = 1;
   this.postMessageTransfers = true;
-  var callbacks = this.callbacks = {};
+  var callbacksCapabilities = this.callbacksCapabilities = {};
   var ah = this.actionHandler = {};
 
   ah['console_log'] = [function ahConsoleLog(data) {
@@ -1383,35 +1383,40 @@ function MessageHandler(name, comObj) {
     var data = event.data;
     if (data.isReply) {
       var callbackId = data.callbackId;
-      if (data.callbackId in callbacks) {
+      if (data.callbackId in callbacksCapabilities) {
-        var callback = callbacks[callbackId];
+        var callback = callbacksCapabilities[callbackId];
-        delete callbacks[callbackId];
+        delete callbacksCapabilities[callbackId];
-        callback(data.data);
+        if ('error' in data) {
+          callback.reject(data.error);
+        } else {
+          callback.resolve(data.data);
+        }
       } else {
         error('Cannot resolve callback ' + callbackId);
       }
     } else if (data.action in ah) {
       var action = ah[data.action];
       if (data.callbackId) {
-        var deferred = {};
+        Promise.resolve().then(function () {
-        var promise = new Promise(function (resolve, reject) {
+          return action[0].call(action[1], data.data);
-          deferred.resolve = resolve;
+        }).then(function (result) {
-          deferred.reject = reject;
-        });
-        deferred.promise = promise;
-        promise.then(function(resolvedData) {
           comObj.postMessage({
             isReply: true,
             callbackId: data.callbackId,
-            data: resolvedData
+            data: result
+          });
+        }, function (reason) {
+          comObj.postMessage({
+            isReply: true,
+            callbackId: data.callbackId,
+            error: reason
           });
         });
-        action[0].call(action[1], data.data, deferred);
       } else {
         action[0].call(action[1], data.data);
       }
     } else {
-      error('Unkown action from worker: ' + data.action);
+      error('Unknown action from worker: ' + data.action);
     }
   };
 }
@@ -1428,19 +1433,48 @@ MessageHandler.prototype = {
    * Sends a message to the comObj to invoke the action with the supplied data.
    * @param {String} actionName Action to call.
    * @param {JSON} data JSON data to send.
-   * @param {function} [callback] Optional callback that will handle a reply.
    * @param {Array} [transfers] Optional list of transfers/ArrayBuffers
    */
-  send: function messageHandlerSend(actionName, data, callback, transfers) {
+  send: function messageHandlerSend(actionName, data, transfers) {
     var message = {
       action: actionName,
       data: data
     };
-    if (callback) {
+    this.postMessage(message, transfers);
-      var callbackId = this.callbackIndex++;
+  },
-      this.callbacks[callbackId] = callback;
+  /**
-      message.callbackId = callbackId;
+   * Sends a message to the comObj to invoke the action with the supplied data.
+   * Expects that other side will callback with the response.
+   * @param {String} actionName Action to call.
+   * @param {JSON} data JSON data to send.
+   * @param {Array} [transfers] Optional list of transfers/ArrayBuffers.
+   * @param {boolean} withPromise true if response if expected.
+   * @returns {Promise} Promise to be resolved with response data.
+   */
+  sendWithPromise:
+    function messageHandlerSendWithPromise(actionName, data, transfers) {
+    var callbackId = this.callbackIndex++;
+    var message = {
+      action: actionName,
+      data: data,
+      callbackId: callbackId
+    };
+    var capability = createPromiseCapability();
+    this.callbacksCapabilities[callbackId] = capability;
+    try {
+      this.postMessage(message, transfers);
+    } catch (e) {
+      capability.reject(e);
     }
+    return capability.promise;
+  },
+  /**
+   * Sends raw message to the comObj.
+   * @private
+   * @param message {Object} Raw message.
+   * @param transfers List of transfers/ArrayBuffers, or undefined.
+   */
+  postMessage: function (message, transfers) {
     if (transfers && this.postMessageTransfers) {
       this.comObj.postMessage(message, transfers);
     } else {