Merge pull request #11107 from Snuffleupagus/MessageHandler-postMessage

Various `MessageHandler` improvements when using Streams

src/display/api.js

@@ -1248,17 +1248,17 @@ class PDFPageProxy {
    */
   _tryCleanup(resetStats = false) {
     if (!this.pendingCleanup ||
-        Object.keys(this.intentStates).some(function(intent) {
+        Object.keys(this.intentStates).some((intent) => {
           const intentState = this.intentStates[intent];
           return (intentState.renderTasks.length !== 0 ||
                   !intentState.operatorList.lastChunk);
-        }, this)) {
+        })) {
       return;
     }
 
-    Object.keys(this.intentStates).forEach(function(intent) {
+    Object.keys(this.intentStates).forEach((intent) => {
       delete this.intentStates[intent];
-    }, this);
+    });
     this.objs.clear();
     this.annotationsPromise = null;
     if (resetStats && this._stats instanceof StatTimer) {
@@ -1443,18 +1443,18 @@ class LoopbackPort {
     }
 
     if (!this._defer) {
-      this._listeners.forEach(function(listener) {
+      this._listeners.forEach((listener) => {
         listener.call(this, { data: obj, });
-      }, this);
+      });
       return;
     }
 
     const cloned = new WeakMap();
     const e = { data: cloneValue(obj), };
     this._deferred.then(() => {
-      this._listeners.forEach(function(listener) {
+      this._listeners.forEach((listener) => {
         listener.call(this, e);
-      }, this);
+      });
     });
   }
 

src/shared/message_handler.js

@@ -18,6 +18,18 @@ import {
   ReadableStream, UnexpectedResponseException, UnknownErrorException
 } from './util';
 
+const StreamKind = {
+  UNKNOWN: 0,
+  CANCEL: 1,
+  CANCEL_COMPLETE: 2,
+  CLOSE: 3,
+  ENQUEUE: 4,
+  ERROR: 5,
+  PULL: 6,
+  PULL_COMPLETE: 7,
+  START_COMPLETE: 8,
+};
+
 async function resolveCall(fn, args, thisArg = null) {
   if (!fn) {
     return undefined;
@@ -36,20 +48,11 @@ function wrapReason(reason) {
       return new MissingPDFException(reason.message);
     case 'UnexpectedResponseException':
       return new UnexpectedResponseException(reason.message, reason.status);
-    default:
+    case 'UnknownErrorException':
       return new UnknownErrorException(reason.message, reason.details);
-  }
+    default:
-}
-
-function makeReasonSerializable(reason) {
-  if (!(reason instanceof Error) ||
-      reason instanceof AbortException ||
-      reason instanceof MissingPDFException ||
-      reason instanceof UnexpectedResponseException ||
-      reason instanceof UnknownErrorException) {
-    return reason;
-  }
       return new UnknownErrorException(reason.message, reason.toString());
+  }
 }
 
 function resolveOrReject(capability, data) {
@@ -113,7 +116,7 @@ function MessageHandler(sourceName, targetName, comObj) {
             targetName,
             isReply: true,
             callbackId: data.callbackId,
-            error: makeReasonSerializable(reason),
+            error: wrapReason(reason),
           });
         });
       } else if (data.streamId) {
@@ -143,13 +146,12 @@ MessageHandler.prototype = {
    * @param {Array} [transfers] - Optional list of transfers/ArrayBuffers
    */
   send(actionName, data, transfers) {
-    var message = {
+    this.postMessage({
       sourceName: this.sourceName,
       targetName: this.targetName,
       action: actionName,
       data,
-    };
+    }, transfers);
-    this.postMessage(message, transfers);
   },
   /**
    * Sends a message to the comObj to invoke the action with the supplied data.
@@ -161,19 +163,18 @@ MessageHandler.prototype = {
    */
   sendWithPromise(actionName, data, transfers) {
     var callbackId = this.callbackId++;
-    var message = {
-      sourceName: this.sourceName,
-      targetName: this.targetName,
-      action: actionName,
-      data,
-      callbackId,
-    };
     var capability = createPromiseCapability();
     this.callbacksCapabilities[callbackId] = capability;
     try {
-      this.postMessage(message, transfers);
+      this.postMessage({
-    } catch (e) {
+        sourceName: this.sourceName,
-      capability.reject(e);
+        targetName: this.targetName,
+        action: actionName,
+        callbackId,
+        data,
+      }, transfers);
+    } catch (ex) {
+      capability.reject(ex);
     }
     return capability.promise;
   },
@@ -191,6 +192,7 @@ MessageHandler.prototype = {
     let streamId = this.streamId++;
     let sourceName = this.sourceName;
     let targetName = this.targetName;
+    const comObj = this.comObj;
 
     return new ReadableStream({
       start: (controller) => {
@@ -207,7 +209,7 @@ MessageHandler.prototype = {
           streamId,
           data,
           desiredSize: controller.desiredSize,
-        });
+        }, transfers);
         // Return Promise for Async process, to signal success/failure.
         return startCapability.promise;
       },
@@ -215,10 +217,10 @@ MessageHandler.prototype = {
       pull: (controller) => {
         let pullCapability = createPromiseCapability();
         this.streamControllers[streamId].pullCall = pullCapability;
-        this.postMessage({
+        comObj.postMessage({
           sourceName,
           targetName,
-          stream: 'pull',
+          stream: StreamKind.PULL,
           streamId,
           desiredSize: controller.desiredSize,
         });
@@ -231,12 +233,12 @@ MessageHandler.prototype = {
         let cancelCapability = createPromiseCapability();
         this.streamControllers[streamId].cancelCall = cancelCapability;
         this.streamControllers[streamId].isClosed = true;
-        this.postMessage({
+        comObj.postMessage({
           sourceName,
           targetName,
-          stream: 'cancel',
+          stream: StreamKind.CANCEL,
-          reason,
           streamId,
+          reason,
         });
         // Return Promise to signal success or failure.
         return cancelCapability.promise;
@@ -252,12 +254,7 @@ MessageHandler.prototype = {
     let sourceName = this.sourceName;
     let targetName = data.sourceName;
     let capability = createPromiseCapability();
-
+    const comObj = this.comObj;
-    let sendStreamRequest = ({ stream, chunk, transfers,
-                               success, reason, }) => {
-      this.postMessage({ sourceName, targetName, stream, streamId,
-                         chunk, success, reason, }, transfers);
-    };
 
     let streamSink = {
       enqueue(chunk, size = 1, transfers) {
@@ -273,7 +270,13 @@ MessageHandler.prototype = {
           this.sinkCapability = createPromiseCapability();
           this.ready = this.sinkCapability.promise;
         }
-        sendStreamRequest({ stream: 'enqueue', chunk, transfers, });
+        self.postMessage({
+          sourceName,
+          targetName,
+          stream: StreamKind.ENQUEUE,
+          streamId,
+          chunk,
+        }, transfers);
       },
 
       close() {
@@ -281,7 +284,12 @@ MessageHandler.prototype = {
           return;
         }
         this.isCancelled = true;
-        sendStreamRequest({ stream: 'close', });
+        comObj.postMessage({
+          sourceName,
+          targetName,
+          stream: StreamKind.CLOSE,
+          streamId,
+        });
         delete self.streamSinks[streamId];
       },
 
@@ -290,7 +298,13 @@ MessageHandler.prototype = {
           return;
         }
         this.isCancelled = true;
-        sendStreamRequest({ stream: 'error', reason, });
+        comObj.postMessage({
+          sourceName,
+          targetName,
+          stream: StreamKind.ERROR,
+          streamId,
+          reason,
+        });
       },
 
       sinkCapability: capability,
@@ -305,9 +319,21 @@ MessageHandler.prototype = {
     streamSink.ready = streamSink.sinkCapability.promise;
     this.streamSinks[streamId] = streamSink;
     resolveCall(action[0], [data.data, streamSink], action[1]).then(() => {
-      sendStreamRequest({ stream: 'start_complete', success: true, });
+      comObj.postMessage({
+        sourceName,
+        targetName,
+        stream: StreamKind.START_COMPLETE,
+        streamId,
+        success: true,
+      });
     }, (reason) => {
-      sendStreamRequest({ stream: 'start_complete', success: false, reason, });
+      comObj.postMessage({
+        sourceName,
+        targetName,
+        stream: StreamKind.START_COMPLETE,
+        streamId,
+        reason,
+      });
     });
   },
 
@@ -315,11 +341,7 @@ MessageHandler.prototype = {
     let sourceName = this.sourceName;
     let targetName = data.sourceName;
     let streamId = data.streamId;
-
+    const comObj = this.comObj;
-    let sendStreamResponse = ({ stream, success, reason, }) => {
-      this.comObj.postMessage({ sourceName, targetName, stream,
-                                success, streamId, reason, });
-    };
 
     let deleteStreamController = () => {
       // Delete the `streamController` only when the start, pull, and cancel
@@ -336,16 +358,22 @@ MessageHandler.prototype = {
     };
 
     switch (data.stream) {
-      case 'start_complete':
+      case StreamKind.START_COMPLETE:
         resolveOrReject(this.streamControllers[data.streamId].startCall, data);
         break;
-      case 'pull_complete':
+      case StreamKind.PULL_COMPLETE:
         resolveOrReject(this.streamControllers[data.streamId].pullCall, data);
         break;
-      case 'pull':
+      case StreamKind.PULL:
         // Ignore any pull after close is called.
         if (!this.streamSinks[data.streamId]) {
-          sendStreamResponse({ stream: 'pull_complete', success: true, });
+          comObj.postMessage({
+            sourceName,
+            targetName,
+            stream: StreamKind.PULL_COMPLETE,
+            streamId,
+            success: true,
+          });
           break;
         }
         // Pull increases the desiredSize property of sink,
@@ -358,20 +386,31 @@ MessageHandler.prototype = {
         // Reset desiredSize property of sink on every pull.
         this.streamSinks[data.streamId].desiredSize = data.desiredSize;
         resolveCall(this.streamSinks[data.streamId].onPull).then(() => {
-          sendStreamResponse({ stream: 'pull_complete', success: true, });
+          comObj.postMessage({
+            sourceName,
+            targetName,
+            stream: StreamKind.PULL_COMPLETE,
+            streamId,
+            success: true,
+          });
         }, (reason) => {
-          sendStreamResponse({ stream: 'pull_complete',
+          comObj.postMessage({
-                               success: false, reason, });
+            sourceName,
+            targetName,
+            stream: StreamKind.PULL_COMPLETE,
+            streamId,
+            reason,
+          });
         });
         break;
-      case 'enqueue':
+      case StreamKind.ENQUEUE:
         assert(this.streamControllers[data.streamId],
                'enqueue should have stream controller');
         if (!this.streamControllers[data.streamId].isClosed) {
           this.streamControllers[data.streamId].controller.enqueue(data.chunk);
         }
         break;
-      case 'close':
+      case StreamKind.CLOSE:
         assert(this.streamControllers[data.streamId],
                'close should have stream controller');
         if (this.streamControllers[data.streamId].isClosed) {
@@ -381,27 +420,38 @@ MessageHandler.prototype = {
         this.streamControllers[data.streamId].controller.close();
         deleteStreamController();
         break;
-      case 'error':
+      case StreamKind.ERROR:
         assert(this.streamControllers[data.streamId],
                'error should have stream controller');
         this.streamControllers[data.streamId].controller.
           error(wrapReason(data.reason));
         deleteStreamController();
         break;
-      case 'cancel_complete':
+      case StreamKind.CANCEL_COMPLETE:
         resolveOrReject(this.streamControllers[data.streamId].cancelCall, data);
         deleteStreamController();
         break;
-      case 'cancel':
+      case StreamKind.CANCEL:
         if (!this.streamSinks[data.streamId]) {
           break;
         }
         resolveCall(this.streamSinks[data.streamId].onCancel,
                     [wrapReason(data.reason)]).then(() => {
-          sendStreamResponse({ stream: 'cancel_complete', success: true, });
+          comObj.postMessage({
+            sourceName,
+            targetName,
+            stream: StreamKind.CANCEL_COMPLETE,
+            streamId,
+            success: true,
+          });
         }, (reason) => {
-          sendStreamResponse({ stream: 'cancel_complete',
+          comObj.postMessage({
-                               success: false, reason, });
+            sourceName,
+            targetName,
+            stream: StreamKind.CANCEL_COMPLETE,
+            streamId,
+            reason,
+          });
         });
         this.streamSinks[data.streamId].sinkCapability.
           reject(wrapReason(data.reason));