fix windows drive volume mounting

agent/api/task/task_windows.go

@@ -74,7 +74,22 @@ func (task *Task) downcaseAllVolumePaths() {
 }
 
 func getCanonicalPath(path string) string {
-	return filepath.Clean(strings.ToLower(path))
+	lowercasedPath := strings.ToLower(path)
+	// if the path is a bare drive like "d:", don't filepath.Clean it because it will add a '.'.
+	// this is to fix the case where mounting from D:\ to D: is supported by docker but not ecs
+	if isBareDrive(lowercasedPath) {
+		return lowercasedPath
+	}
+
+	return filepath.Clean(lowercasedPath)
+}
+
+func isBareDrive(path string) bool {
+	if filepath.VolumeName(path) == path {
+		return true
+	}
+
+	return false
 }
 
 // platformHostConfigOverride provides an entry point to set up default HostConfig options to be

agent/api/task/task_windows_test.go

@@ -295,3 +295,29 @@ func TestCPUPercentBasedOnUnboundedEnabled(t *testing.T) {
 		})
 	}
 }
+
+func TestGetCanonicalPath(t *testing.T) {
+	testcases := []struct {
+		name           string
+		path           string
+		expectedResult string
+	}{
+		{
+			name:           "folderPath",
+			path:           `C:\myFile`,
+			expectedResult: `c:\myfile`,
+		},
+		{
+			name:           "drivePath",
+			path:           `D:`,
+			expectedResult: `d:`,
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			result := getCanonicalPath(tc.path)
+			assert.Equal(t, result, tc.expectedResult)
+		})
+	}
+}