Improve error if we cannot determine if source is a directory (#1412)

* Improve error if we cannot determine if source is a directory

* Replace ste logger with scanning logger

* Undo white space changes

* Fix CI

Author: nakulkar-msft

cmd/zc_traverser_blob.go

@@ -72,7 +72,7 @@ func (t *blobTraverser) IsDirectory(isSource bool) bool {
 		return isDirDirect
 	}
 
-	_, isSingleBlob, _, err := t.getPropertiesIfSingleBlob()
+	_, _, isDirStub, err := t.getPropertiesIfSingleBlob()
 
 	if stgErr, ok := err.(azblob.StorageError); ok {
 		// We know for sure this is a single blob still, let it walk on through to the traverser.
@@ -81,7 +81,29 @@ func (t *blobTraverser) IsDirectory(isSource bool) bool {
 		}
 	}
 
-	return !isSingleBlob
+	if err == nil {
+		return isDirStub
+	}
+
+	blobURLParts := azblob.NewBlobURLParts(*t.rawURL)
+	containerRawURL := copyHandlerUtil{}.getContainerUrl(blobURLParts)
+	containerURL := azblob.NewContainerURL(containerRawURL, t.p)
+	searchPrefix := strings.TrimSuffix(blobURLParts.BlobName, common.AZCOPY_PATH_SEPARATOR_STRING) + common.AZCOPY_PATH_SEPARATOR_STRING
+	resp, err := containerURL.ListBlobsFlatSegment(t.ctx, azblob.Marker{}, azblob.ListBlobsSegmentOptions{Prefix: searchPrefix, MaxResults: 1})
+	if err != nil {
+		if azcopyScanningLogger != nil {
+			msg := fmt.Sprintf("Failed to check if the destination is a folder or a file (Azure Files). Assuming the destination is a file: %s", err)
+			azcopyScanningLogger.Log(pipeline.LogError, msg)
+		}
+		return false
+	}
+
+	if len(resp.Segment.BlobItems) == 0 {
+		//Not a directory
+		return false
+	}
+
+	return true
 }
 
 func (t *blobTraverser) getPropertiesIfSingleBlob() (props *azblob.BlobGetPropertiesResponse, isBlob bool, isDirStub bool, err error) {

cmd/zt_sync_blob_blob_test.go

@@ -482,7 +482,7 @@ func (s *cmdIntegrationSuite) TestSyncS2SContainerAndEmptyVirtualDir(c *chk.C) {
 
 	// construct the raw input to simulate user input
 	srcContainerURLWithSAS := scenarioHelper{}.getRawContainerURLWithSAS(c, srcContainerName)
-	dstVirtualDirURLWithSAS := scenarioHelper{}.getRawBlobURLWithSAS(c, dstContainerName, "emptydir")
+	dstVirtualDirURLWithSAS := scenarioHelper{}.getRawBlobURLWithSAS(c, dstContainerName, "emptydir/")
 	raw := getDefaultSyncRawInput(srcContainerURLWithSAS.String(), dstVirtualDirURLWithSAS.String())
 
 	// verify that targeting a virtual directory works fine

testSuite/scripts/test_blob_sync.py

@@ -71,7 +71,7 @@ def test_sync_entire_directory_with_local(self):
 
         # sync to local
         src = vdir_sas
-        dst = dir_path
+        dst = dir_path + "/"
         result = util.Command("sync").add_arguments(src).add_arguments(dst).add_flags("log-level", "info")\
             .execute_azcopy_copy_command()
         self.assertTrue(result)
@@ -116,7 +116,7 @@ def test_sync_entire_vdir_to_vdir(self):
         content_dir_name = "dir_sync_test"
         content_dir_path = util.create_test_n_files(1024, 10, content_dir_name)
         src_vdir_path = util.get_resource_sas("srcdir")
-        dst_vdir_path = util.get_resource_sas("dstdir")
+        dst_vdir_path = util.get_resource_sas("dstdir/")
 
         # create sub-directory inside directory
         sub_dir_name = os.path.join(content_dir_name, "sub_dir_sync_test")