fix: 🐛 Handle failed loads when fetching data (#107)

Author: JamesAPetts

src/lib/getImageData.js

@@ -79,7 +79,13 @@ export default function getImageData(imageIds, displaySetInstanceUid) {
     });
   };
 
-  const _publishAllPixelDataInseted = () => {
+  const _publishPixelDataInsertedError = error => {
+    imageDataObject.subscriptions.onPixelDataInsertedError.forEach(callback => {
+      callback(error);
+    });
+  };
+
+  const _publishAllPixelDataInserted = () => {
     imageDataObject.subscriptions.onAllPixelDataInserted.forEach(callback => {
       callback();
     });
@@ -90,6 +96,7 @@ export default function getImageData(imageIds, displaySetInstanceUid) {
     // Remove all subscriptions on completion.
     imageDataObject.subscriptions = {
       onPixelDataInserted: [],
+      onPixelDataInsertedError: [],
       onAllPixelDataInserted: [],
     };
   };
@@ -108,16 +115,21 @@ export default function getImageData(imageIds, displaySetInstanceUid) {
     loaded: false,
     subscriptions: {
       onPixelDataInserted: [],
+      onPixelDataInsertedError: [],
       onAllPixelDataInserted: [],
     },
     onPixelDataInserted: callback => {
       imageDataObject.subscriptions.onPixelDataInserted.push(callback);
     },
+    onPixelDataInsertedError: callback => {
+      imageDataObject.subscriptions.onPixelDataInsertedError.push(callback);
+    },
     onAllPixelDataInserted: callback => {
       imageDataObject.subscriptions.onAllPixelDataInserted.push(callback);
     },
     _publishPixelDataInserted,
-    _publishAllPixelDataInseted,
+    _publishAllPixelDataInserted,
+    _publishPixelDataInsertedError,
   };
 
   imageDataCache.set(displaySetInstanceUid, imageDataObject);

src/lib/loadImageData.js

@@ -55,6 +55,16 @@ export default function loadImageDataProgressively(imageDataObject) {
   const reRenderFraction = numberOfFrames / 5;
   let reRenderTarget = reRenderFraction;
 
+  const insertPixelDataErrorHandler = error => {
+    numberProcessed++;
+    imageDataObject._publishPixelDataInsertedError(error);
+
+    if (numberProcessed === numberOfFrames) {
+      // Done loading, publish complete and remove all subscriptions.
+      imageDataObject._publishAllPixelDataInserted();
+    }
+  };
+
   const insertPixelData = image => {
     const { imagePositionPatient } = metaDataMap.get(image.imageId);
 
@@ -93,27 +103,29 @@ export default function loadImageDataProgressively(imageDataObject) {
 
     if (numberProcessed === numberOfFrames) {
       // Done loading, publish complete and remove all subscriptions.
-      imageDataObject._publishAllPixelDataInseted();
+      imageDataObject._publishAllPixelDataInserted();
     }
   };
 
-  prefetchImageIds(imageIds, imageDataObject, insertPixelData);
+  prefetchImageIds(imageIds, insertPixelData, insertPixelDataErrorHandler);
 }
 
 const requestType = 'prefetch';
 const preventCache = false;
 
-function prefetchImageIds(imageIds, imageDataObject, insertPixelData) {
-  const noop = () => {};
-
+function prefetchImageIds(
+  imageIds,
+  insertPixelData,
+  insertPixelDataErrorHandler
+) {
   imageIds.forEach(imageId => {
     requestPoolManager.addRequest(
       {},
       imageId,
       requestType,
       preventCache,
       insertPixelData,
-      noop
+      insertPixelDataErrorHandler
     );
   });