xl/fs: Return InvalidPart{} error for part ETag mismatch. (#4541)

Fixes #4539

cmd/api-errors.go

@@ -317,7 +317,7 @@ var errorCodeResponse = map[APIErrorCode]APIError{
 	},
 	ErrInvalidPart: {
 		Code:           "InvalidPart",
-		Description:    "One or more of the specified parts could not be found.",
+		Description:    "One or more of the specified parts could not be found.  The part may not have been uploaded, or the specified entity tag may not match the part's entity tag.",
 		HTTPStatusCode: http.StatusBadRequest,
 	},
 	ErrInvalidPartOrder: {

cmd/fs-v1-multipart.go

@@ -808,7 +808,7 @@ func (fs fsObjects) CompleteMultipartUpload(bucket string, object string, upload
 
 			if fsMeta.Parts[partIdx].ETag != part.ETag {
 				fs.rwPool.Close(fsMetaPathMultipart)
-				return ObjectInfo{}, traceError(BadDigest{})
+				return ObjectInfo{}, traceError(InvalidPart{})
 			}
 
 			// All parts except the last part has to be atleast 5MB.

cmd/object-api-errors.go

@@ -307,7 +307,7 @@ func (e InvalidUploadID) Error() string {
 type InvalidPart struct{}
 
 func (e InvalidPart) Error() string {
-	return "One or more of the specified parts could not be found"
+	return "One or more of the specified parts could not be found. The part may not have been uploaded, or the specified entity tag may not match the part's entity tag."
 }
 
 // PartTooSmall - error if part size is less than 5MB.

cmd/object-api-multipart_test.go

@@ -1895,7 +1895,7 @@ func testObjectCompleteMultipartUpload(obj ObjectLayer, instanceType string, t T
 		// Part number 0 doesn't exist, expecting InvalidPart error (Test number 12).
 		{bucketNames[0], objectNames[0], uploadIDs[0], []completePart{{ETag: "abcd", PartNumber: 0}}, "", InvalidPart{}, false},
 		// // Upload and PartNumber exists, But a deliberate ETag mismatch is introduced (Test number 13).
-		{bucketNames[0], objectNames[0], uploadIDs[0], inputParts[0].parts, "", BadDigest{}, false},
+		{bucketNames[0], objectNames[0], uploadIDs[0], inputParts[0].parts, "", InvalidPart{}, false},
 		// Test case with non existent object name (Test number 14).
 		{bucketNames[0], "my-object", uploadIDs[0], []completePart{{ETag: "abcd", PartNumber: 1}}, "", InvalidUploadID{UploadID: uploadIDs[0]}, false},
 		// Testing for Part being too small (Test number 15).

cmd/object-handlers_test.go

@@ -2252,7 +2252,7 @@ func testAPICompleteMultipartHandler(obj ObjectLayer, instanceType, bucketName s
 			accessKey: credentials.AccessKey,
 			secretKey: credentials.SecretKey,
 
-			expectedContent: encodeResponse(getAPIErrorResponse(getAPIError(toAPIErrorCode(BadDigest{})),
+			expectedContent: encodeResponse(getAPIErrorResponse(getAPIError(toAPIErrorCode(InvalidPart{})),
 				getGetObjectURL("", bucketName, objectName))),
 			expectedRespStatus: http.StatusBadRequest,
 		},

cmd/xl-v1-multipart.go

@@ -936,7 +936,7 @@ func (xl xlObjects) CompleteMultipartUpload(bucket string, object string, upload
 
 		// All parts should have same ETag as previously generated.
 		if currentXLMeta.Parts[partIdx].ETag != part.ETag {
-			return ObjectInfo{}, traceError(BadDigest{})
+			return ObjectInfo{}, traceError(InvalidPart{})
 		}
 
 		// All parts except the last part has to be atleast 5MB.