Enhancement for format error message

- add yaml format error handler
- silent usage when build command fails

pkg/internal/error/yamlformaterror.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package error has contextual error types.
+package error
+
+import (
+	"fmt"
+
+	yaml "k8s.io/apimachinery/pkg/util/yaml"
+)
+
+// YamlFormatError represents error with yaml file name where json/yaml format error happens.
+type YamlFormatError struct {
+	Path     string
+	ErrorMsg string
+}
+
+func (e YamlFormatError) Error() string {
+	return fmt.Sprintf("YAML file [%s] encounters a format error.\n%s\n", e.Path, e.ErrorMsg)
+}
+
+// ErrorHandler handles YamlFormatError
+func ErrorHandler(e error, path string) error {
+	if err, ok := e.(yaml.YAMLSyntaxError); ok {
+		return YamlFormatError{
+			Path:     path,
+			ErrorMsg: err.Error(),
+		}
+	}
+	return e
+}