add function to run kustomize build

staging/src/BUILD

@@ -110,6 +110,7 @@ filegroup(
         "//staging/src/k8s.io/apiserver/plugin/pkg/authorizer/webhook:all-srcs",
         "//staging/src/k8s.io/cli-runtime/artifacts:all-srcs",
         "//staging/src/k8s.io/cli-runtime/pkg/genericclioptions:all-srcs",
+        "//staging/src/k8s.io/cli-runtime/pkg/kustomize:all-srcs",
         "//staging/src/k8s.io/client-go/deprecated-dynamic:all-srcs",
         "//staging/src/k8s.io/client-go/discovery:all-srcs",
         "//staging/src/k8s.io/client-go/dynamic:all-srcs",

staging/src/k8s.io/cli-runtime/pkg/kustomize/builder.go

+/*
+Copyright 2019 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 kustomize
+
+import (
+	"io"
+
+	"k8s.io/cli-runtime/pkg/kustomize/k8sdeps"
+	"sigs.k8s.io/kustomize/pkg/commands/build"
+	"sigs.k8s.io/kustomize/pkg/fs"
+)
+
+// RunKustomizeBuild runs kustomize build given a filesystem and a path
+func RunKustomizeBuild(out io.Writer, fSys fs.FileSystem, path string) error {
+	f := k8sdeps.NewFactory()
+	o := build.NewOptions(path, "")
+	return o.RunBuild(out, fSys, f.ResmapF, f.TransformerF)
+}

staging/src/k8s.io/cli-runtime/pkg/kustomize/builder_test.go

+/*
+Copyright 2019 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 kustomize
+
+import (
+	"bytes"
+	"testing"
+
+	"sigs.k8s.io/kustomize/pkg/fs"
+)
+
+const (
+	kustomizationContent1 = `
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+namePrefix: foo-
+nameSuffix: -bar
+namespace: ns1
+commonLabels:
+  app: nginx
+commonAnnotations:
+  note: This is a test annotation
+resources:
+  - deployment.yaml
+  - namespace.yaml
+configMapGenerator:
+- name: literalConfigMap
+  literals:
+  - DB_USERNAME=admin
+  - DB_PASSWORD=somepw
+secretGenerator:
+- name: secret
+  literals:
+    - DB_USERNAME=admin
+    - DB_PASSWORD=somepw
+  type: Opaque
+patchesJson6902:
+- target:
+    group: apps
+    version: v1
+    kind: Deployment
+    name: dply1
+  path: jsonpatch.json
+`
+	deploymentContent = `
+apiVersion: apps/v1
+metadata:
+  name: dply1
+kind: Deployment
+`
+	namespaceContent = `
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: ns1
+`
+	jsonpatchContent = `[
+    {"op": "add", "path": "/spec/replica", "value": "3"}
+]`
+
+	expectedContent = `apiVersion: v1
+kind: Namespace
+metadata:
+  annotations:
+    note: This is a test annotation
+  labels:
+    app: nginx
+  name: foo-ns1-bar
+---
+apiVersion: v1
+data:
+  DB_PASSWORD: somepw
+  DB_USERNAME: admin
+kind: ConfigMap
+metadata:
+  annotations:
+    note: This is a test annotation
+  labels:
+    app: nginx
+  name: foo-literalConfigMap-bar-8d2dkb8k24
+  namespace: ns1
+---
+apiVersion: v1
+data:
+  DB_PASSWORD: c29tZXB3
+  DB_USERNAME: YWRtaW4=
+kind: Secret
+metadata:
+  annotations:
+    note: This is a test annotation
+  labels:
+    app: nginx
+  name: foo-secret-bar-9btc7bt4kb
+  namespace: ns1
+type: Opaque
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  annotations:
+    note: This is a test annotation
+  labels:
+    app: nginx
+  name: foo-dply1-bar
+  namespace: ns1
+spec:
+  replica: "3"
+  selector:
+    matchLabels:
+      app: nginx
+  template:
+    metadata:
+      annotations:
+        note: This is a test annotation
+      labels:
+        app: nginx
+`
+)
+
+func TestResources1(t *testing.T) {
+	fSys := fs.MakeFakeFS()
+	fSys.WriteFile("/kustomization.yaml", []byte(kustomizationContent1))
+	fSys.WriteFile("/deployment.yaml", []byte(deploymentContent))
+	fSys.WriteFile("/namespace.yaml", []byte(namespaceContent))
+	fSys.WriteFile("/jsonpatch.json", []byte(jsonpatchContent))
+
+	var out bytes.Buffer
+	err := RunKustomizeBuild(&out, fSys, "/")
+	if err != nil {
+		t.Fatalf("unexpected Resources error %v", err)
+	}
+
+	if out.String() != expectedContent {
+		t.Fatalf("expected:\n%s\nbut got:\n%s", expectedContent, out.String())
+	}
+}