improve handling of FileReader errors, test added

Author: Kirill Semenov

evaporate.js

@@ -1422,6 +1422,7 @@
             SignedS3AWSRequest.prototype.send.call(self);
           });
     }
+    return Promise.resolve();
   };
   PutPart.prototype.success = function () {
     clearInterval(this.stalledInterval);
@@ -1467,14 +1468,31 @@
     return [CANCELED, ABORTED, PAUSED, PAUSING].indexOf(this.fileUpload.status) > -1;
   };
   PutPart.prototype.delaySend = function () {
+    var that = this;
     var backOffWait = this.backOffWait();
     this.attempts += 1;
-    setTimeout(this.send.bind(this), backOffWait);
+    setTimeout(function() {
+      that.send().catch(
+        function(e) {
+        l.w(e);
+      });
+     }, backOffWait);
   };
   PutPart.prototype.errorHandler = function (reason) {
     clearInterval(this.stalledInterval);
-    if (reason.match(/status:404/)) {
-      var errMsg = '404 error on part PUT. The part and the file will abort. ' + reason;
+    var hasError = false;
+    var errMsg = "Unexpected error occured";
+    if (reason instanceof DOMException) {
+      this.fileUpload.stopMonitor();
+      errMsg = "Error reading file. " + reason;
+      hasError = true;
+    }
+    else if (reason.match(/status:404/)) {
+      errMsg = '404 error on part PUT. The part and the file will abort. ' + reason;
+      hasError = true;
+    }
+
+    if (hasError) {
       l.w(errMsg);
       this.fileUpload.error(errMsg);
       this.part.status = ABORTED;
@@ -1560,16 +1578,18 @@
         slicerFn = (file.slice ? 'slice' : (file.mozSlice ? 'mozSlice' : 'webkitSlice')),
         blob = file[slicerFn](this.start, this.end);
     if (this.con.computeContentMd5) {
-      return new Promise(function (resolve) {
+      return new Promise(function (resolve, reject) {
         var reader = new FileReader();
         reader.onloadend = function () {
+          if (this.error) {
+            that.errorHandler(this.error);
+            reject(this.error.message);
+            return;
+          }
           var buffer = this.result && typeof this.result.buffer !== 'undefined',
               result = buffer ? new Uint8Array(this.result.buffer) : this.result;
           resolve(result);
         };
-        reader.onerror = function() {
-        	that.fileUpload.error("Problem occured while reading file " + file.name);
-        };
         reader.readAsArrayBuffer(blob);
       });
     }

test/common-case.spec.js

@@ -6,6 +6,11 @@ import test from 'ava'
 
 let server
 
+if (!global.DOMException) {
+	global.DOMException = function() {
+		this.error = undefined
+	}
+}
 function testCommon(t, addConfig, initConfig) {
   let evapConfig = Object.assign({}, {awsSignatureVersion: '2'}, initConfig)
   return testBase(t, addConfig, evapConfig)
@@ -405,3 +410,36 @@ test('should fail with the correctly ordered requests when PUT part 404s and DEL
         expect(requestOrder(t)).to.match(/initiate,PUT:partNumber=1,cancel,cancel/)
       })
 })
+
+// Failure on FileReader read error is propagated
+test.serial('should propagate error when FileReader api fails', (t) => {
+	var arrayBuffer = global['FileReader'].prototype.readAsArrayBuffer;
+
+	global.FileReader.prototype.readAsArrayBuffer = function(blob)
+	{
+		this.error = new DOMException();
+		this.onloadend();
+	};
+
+	const config = {
+		name: randomAwsKey(),
+		file: new File({
+			path: '/tmp/file',
+			size: 8,
+			name: randomAwsKey()
+		}),
+		computeContentMd5: true,
+		cryptoMd5Method: function () { return 'MD5Value'; },
+	}
+
+	return testCommon(t, config, config)
+		.then(
+			function (result) {
+				global['FileReader'].prototype.readAsArrayBuffer = arrayBuffer
+				t.fail('Expected upload to fail but it did not.')
+			},
+			function (reason) {
+				global['FileReader'].prototype.readAsArrayBuffer = arrayBuffer
+				expect(reason).to.match(/aborted/i)
+			})
+})