Add image transformer

pkg/image/imagetag.go

@@ -0,0 +1,31 @@
+/*
+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 image
+
+// Tag contains an image and a new tag, which will replace the original tag.
+// Tag usage is deprecated, instead use ImageTag.
+type Tag struct {
+	// Name is a tag-less image name.
+	Name string `json:"name,omitempty" yaml:"name,omitempty"`
+
+	// NewTag is the value to use in replacing the original tag.
+	NewTag string `json:"newTag,omitempty" yaml:"newTag,omitempty"`
+
+	// Digest is the value used to replace the original image tag.
+	// If digest is present NewTag value is ignored.
+	Digest string `json:"digest,omitempty" yaml:"digest,omitempty"`
+}