Merge pull request #45 from monopole/createDiffPackage

Create and document diff package.

pkg/commands/build.go

@@ -27,7 +27,6 @@ import (
 	"github.com/kubernetes-sigs/kustomize/pkg/app"
 	"github.com/kubernetes-sigs/kustomize/pkg/constants"
 	"github.com/kubernetes-sigs/kustomize/pkg/loader"
-	kutil "github.com/kubernetes-sigs/kustomize/pkg/util"
 	"github.com/kubernetes-sigs/kustomize/pkg/util/fs"
 )
 
@@ -94,7 +93,7 @@ func (o *buildOptions) RunBuild(out, errOut io.Writer, fs fs.FileSystem) error {
 	}
 
 	// Output the objects.
-	res, err := kutil.Encode(allResources)
+	res, err := allResources.EncodeAsYaml()
 	if err != nil {
 		return err
 	}

pkg/commands/diff.go

@@ -25,10 +25,9 @@ import (
 
 	"github.com/kubernetes-sigs/kustomize/pkg/app"
 	"github.com/kubernetes-sigs/kustomize/pkg/constants"
+	"github.com/kubernetes-sigs/kustomize/pkg/diff"
 	"github.com/kubernetes-sigs/kustomize/pkg/loader"
-	"github.com/kubernetes-sigs/kustomize/pkg/util"
 	"github.com/kubernetes-sigs/kustomize/pkg/util/fs"
-	"k8s.io/utils/exec"
 )
 
 type diffOptions struct {
@@ -68,12 +67,6 @@ func (o *diffOptions) Validate(cmd *cobra.Command, args []string) error {
 
 // RunDiff gets the differences between Application.Resources() and Application.RawResources().
 func (o *diffOptions) RunDiff(out, errOut io.Writer, fs fs.FileSystem) error {
-	printer := util.Printer{}
-	diff := util.DiffProgram{
-		Exec:   exec.New(),
-		Stdout: out,
-		Stderr: errOut,
-	}
 
 	l := loader.Init([]loader.SchemeLoader{loader.NewFileLoader(fs)})
 
@@ -91,7 +84,7 @@ func (o *diffOptions) RunDiff(out, errOut io.Writer, fs fs.FileSystem) error {
 	if err != nil {
 		return err
 	}
-	resources, err := application.Resources()
+	transformedResources, err := application.Resources()
 	if err != nil {
 		return err
 	}
@@ -100,17 +93,5 @@ func (o *diffOptions) RunDiff(out, errOut io.Writer, fs fs.FileSystem) error {
 		return err
 	}
 
-	transformedDir, err := util.WriteToDir(resources, "transformed", printer)
-	if err != nil {
-		return err
-	}
-	defer transformedDir.Delete()
-
-	noopDir, err := util.WriteToDir(rawResources, "noop", printer)
-	if err != nil {
-		return err
-	}
-	defer noopDir.Delete()
-
-	return diff.Run(noopDir.Name, transformedDir.Name)
+	return diff.RunDiff(rawResources, transformedResources, out, errOut)
 }

pkg/diff/directory.go

@@ -0,0 +1,38 @@
+package diff
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+// directory represents a new temp directory and lets one create files in it.
+type directory struct {
+	n string
+}
+
+// newDirectory makes a directory instance holding a new temp directory on disk.
+// The directory name is the given prefix following by a random string.
+func newDirectory(prefix string) (*directory, error) {
+	name, err := ioutil.TempDir("", prefix+"-")
+	if err != nil {
+		return nil, err
+	}
+
+	return &directory{n: name}, nil
+}
+
+// newFile creates a new file in the directory.
+func (d *directory) newFile(name string) (*os.File, error) {
+	return os.OpenFile(filepath.Join(d.n, name), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0700)
+}
+
+// delete removes the directory recursively.
+func (d *directory) delete() error {
+	return os.RemoveAll(d.n)
+}
+
+// name is the name of the directory.
+func (d *directory) name() string {
+	return d.n
+}

pkg/diff/doc.go

@@ -0,0 +1,2 @@
+// Package diff runs system diff to compare resource collections
+package diff

pkg/diff/program.go

@@ -0,0 +1,59 @@
+/*
+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 diff
+
+import (
+	"io"
+	"os"
+
+	"k8s.io/utils/exec"
+)
+
+// program wraps the system diff program.
+// If specified, the value of KUBERNETES_EXTERNAL_DIFF environment variable
+// will be used instead of simply `diff(1)`.
+type program struct {
+	stdout io.Writer
+	stderr io.Writer
+}
+
+func newProgram(out, errOut io.Writer) *program {
+	return &program{
+		stdout: out,
+		stderr: errOut,
+	}
+}
+
+func (d *program) makeCommand(args ...string) exec.Cmd {
+	diff := ""
+	if envDiff := os.Getenv("KUBERNETES_EXTERNAL_DIFF"); envDiff != "" {
+		diff = envDiff
+	} else {
+		diff = "diff"
+		args = append([]string{"-u", "-N"}, args...)
+	}
+	cmd := exec.New().Command(diff, args...)
+	cmd.SetStdout(d.stdout)
+	cmd.SetStderr(d.stderr)
+	return cmd
+}
+
+// run runs the detected diff program. `from` and `to` are the directory to diff.
+func (d *program) run(from, to string) error {
+	d.makeCommand(from, to).Run() // Ignore diff return code
+	return nil
+}

pkg/diff/rundiff.go

@@ -0,0 +1,63 @@
+package diff
+
+import (
+	"github.com/ghodss/yaml"
+
+	"io"
+
+	"github.com/kubernetes-sigs/kustomize/pkg/resource"
+)
+
+// RunDiff runs system diff program to compare two ResourceCollections.
+func RunDiff(raw, transformed resource.ResourceCollection,
+	out, errOut io.Writer) error {
+	transformedDir, err := writeYamlToNewDir(transformed, "transformed")
+	if err != nil {
+		return err
+	}
+	defer transformedDir.delete()
+
+	noopDir, err := writeYamlToNewDir(raw, "noop")
+	if err != nil {
+		return err
+	}
+	defer noopDir.delete()
+
+	return newProgram(out, errOut).run(noopDir.name(), transformedDir.name())
+}
+
+// writeYamlToNewDir writes each obj in ResourceCollection to a file in a new directory.
+// The directory's name will begin with the given prefix.
+// Each file is named with GroupVersionKindName.
+func writeYamlToNewDir(in resource.ResourceCollection, prefix string) (*directory, error) {
+	dir, err := newDirectory(prefix)
+	if err != nil {
+		return nil, err
+	}
+
+	for gvkn, obj := range in {
+		f, err := dir.newFile(gvkn.String())
+		if err != nil {
+			return nil, err
+		}
+		err = print(obj.Data, f)
+		f.Close()
+		if err != nil {
+			return nil, err
+		}
+	}
+	return dir, nil
+}
+
+// Print the object as YAML.
+func print(obj interface{}, w io.Writer) error {
+	if obj == nil {
+		return nil
+	}
+	data, err := yaml.Marshal(obj)
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(data)
+	return err
+}

pkg/resource/resource.go

@@ -17,7 +17,11 @@ limitations under the License.
 package resource
 
 import (
+	"bytes"
 	"encoding/json"
+	"sort"
+
+	"github.com/ghodss/yaml"
 
 	"github.com/kubernetes-sigs/kustomize/pkg/types"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -41,9 +45,6 @@ func (r *Resource) GVKN() types.GroupVersionKindName {
 	return types.GroupVersionKindName{GVK: gvk, Name: r.Data.GetName()}
 }
 
-// ResourceCollection is a map from GroupVersionKindName to Resource
-type ResourceCollection map[types.GroupVersionKindName]*Resource
-
 func objectToUnstructured(in runtime.Object) (*unstructured.Unstructured, error) {
 	marshaled, err := json.Marshal(in)
 	if err != nil {
@@ -53,3 +54,38 @@ func objectToUnstructured(in runtime.Object) (*unstructured.Unstructured, error)
 	err = out.UnmarshalJSON(marshaled)
 	return &out, err
 }
+
+// ResourceCollection is a map from GroupVersionKindName to Resource
+type ResourceCollection map[types.GroupVersionKindName]*Resource
+
+// EncodeAsYaml encodes the map `in` and output the encoded objects separated by `---`.
+func (in ResourceCollection) EncodeAsYaml() ([]byte, error) {
+	gvknList := []types.GroupVersionKindName{}
+	for gvkn := range in {
+		gvknList = append(gvknList, gvkn)
+	}
+	sort.Sort(types.ByGVKN(gvknList))
+
+	firstObj := true
+	var b []byte
+	buf := bytes.NewBuffer(b)
+	for _, gvkn := range gvknList {
+		obj := in[gvkn].Data
+		out, err := yaml.Marshal(obj)
+		if err != nil {
+			return nil, err
+		}
+		if !firstObj {
+			_, err = buf.WriteString("---\n")
+			if err != nil {
+				return nil, err
+			}
+		}
+		_, err = buf.Write(out)
+		if err != nil {
+			return nil, err
+		}
+		firstObj = false
+	}
+	return buf.Bytes(), nil
+}

pkg/resource/resource_test.go

@@ -14,15 +14,12 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package util
+package resource
 
 import (
-	"fmt"
 	"reflect"
 	"testing"
 
-	"github.com/kubernetes-sigs/kustomize/pkg/resource"
-	"github.com/kubernetes-sigs/kustomize/pkg/types"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 )
@@ -38,11 +35,11 @@ kind: ConfigMap
 metadata:
   name: cm2
 `)
-	input := resource.ResourceCollection{
+	input := ResourceCollection{
 		{
 			GVK:  schema.GroupVersionKind{Version: "v1", Kind: "ConfigMap"},
 			Name: "cm1",
-		}: &resource.Resource{
+		}: &Resource{
 			Data: &unstructured.Unstructured{
 				Object: map[string]interface{}{
 					"apiVersion": "v1",
@@ -56,7 +53,7 @@ metadata:
 		{
 			GVK:  schema.GroupVersionKind{Version: "v1", Kind: "ConfigMap"},
 			Name: "cm2",
-		}: &resource.Resource{
+		}: &Resource{
 			Data: &unstructured.Unstructured{
 				Object: map[string]interface{}{
 					"apiVersion": "v1",
@@ -68,7 +65,7 @@ metadata:
 			},
 		},
 	}
-	out, err := Encode(input)
+	out, err := input.EncodeAsYaml()
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -76,27 +73,3 @@ metadata:
 		t.Fatalf("%s doesn't match expected %s", out, encoded)
 	}
 }
-
-func compareMap(m1, m2 resource.ResourceCollection) error {
-	if len(m1) != len(m2) {
-		keySet1 := []types.GroupVersionKindName{}
-		keySet2 := []types.GroupVersionKindName{}
-		for GVKn := range m1 {
-			keySet1 = append(keySet1, GVKn)
-		}
-		for GVKn := range m1 {
-			keySet2 = append(keySet2, GVKn)
-		}
-		return fmt.Errorf("maps has different number of entries: %#v doesn't equals %#v", keySet1, keySet2)
-	}
-	for GVKn, obj1 := range m1 {
-		obj2, found := m2[GVKn]
-		if !found {
-			return fmt.Errorf("%#v doesn't exist in %#v", GVKn, m2)
-		}
-		if !reflect.DeepEqual(obj1, obj2) {
-			return fmt.Errorf("%#v doesn't match %#v", obj1, obj2)
-		}
-	}
-	return nil
-}

pkg/util/diff.go

@@ -1,104 +0,0 @@
-/*
-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 util
-
-import (
-	"io"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-
-	"github.com/ghodss/yaml"
-
-	"k8s.io/utils/exec"
-)
-
-// DiffProgram finds and run the diff program. The value of
-// KUBERNETES_EXTERNAL_DIFF environment variable will be used a diff
-// program. By default, `diff(1)` will be used.
-type DiffProgram struct {
-	Exec   exec.Interface
-	Stdout io.Writer
-	Stderr io.Writer
-}
-
-func (d *DiffProgram) getCommand(args ...string) exec.Cmd {
-	diff := ""
-	if envDiff := os.Getenv("KUBERNETES_EXTERNAL_DIFF"); envDiff != "" {
-		diff = envDiff
-	} else {
-		diff = "diff"
-		args = append([]string{"-u", "-N"}, args...)
-	}
-
-	cmd := d.Exec.Command(diff, args...)
-	cmd.SetStdout(d.Stdout)
-	cmd.SetStderr(d.Stderr)
-
-	return cmd
-}
-
-// Run runs the detected diff program. `from` and `to` are the directory to diff.
-func (d *DiffProgram) Run(from, to string) error {
-	d.getCommand(from, to).Run() // Ignore diff return code
-	return nil
-}
-
-// Printer is used to print an object.
-type Printer struct{}
-
-// Print the object inside the writer w.
-func (p *Printer) Print(obj interface{}, w io.Writer) error {
-	if obj == nil {
-		return nil
-	}
-	data, err := yaml.Marshal(obj)
-	if err != nil {
-		return err
-	}
-	_, err = w.Write(data)
-	return err
-
-}
-
-// Directory creates a new temp directory, and allows to easily create new files.
-type Directory struct {
-	Name string
-}
-
-// CreateDirectory does create the actual disk directory, and return a
-// new representation of it.
-func CreateDirectory(prefix string) (*Directory, error) {
-	name, err := ioutil.TempDir("", prefix+"-")
-	if err != nil {
-		return nil, err
-	}
-
-	return &Directory{
-		Name: name,
-	}, nil
-}
-
-// NewFile creates a new file in the directory.
-func (d *Directory) NewFile(name string) (*os.File, error) {
-	return os.OpenFile(filepath.Join(d.Name, name), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0700)
-}
-
-// Delete removes the directory recursively.
-func (d *Directory) Delete() error {
-	return os.RemoveAll(d.Name)
-}

pkg/util/util.go

@@ -1,80 +0,0 @@
-/*
-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 util
-
-import (
-	"bytes"
-	"sort"
-
-	"github.com/ghodss/yaml"
-
-	"github.com/kubernetes-sigs/kustomize/pkg/resource"
-	"github.com/kubernetes-sigs/kustomize/pkg/types"
-)
-
-// Encode encodes the map `in` and output the encoded objects separated by `---`.
-func Encode(in resource.ResourceCollection) ([]byte, error) {
-	gvknList := []types.GroupVersionKindName{}
-	for gvkn := range in {
-		gvknList = append(gvknList, gvkn)
-	}
-	sort.Sort(types.ByGVKN(gvknList))
-
-	firstObj := true
-	var b []byte
-	buf := bytes.NewBuffer(b)
-	for _, gvkn := range gvknList {
-		obj := in[gvkn].Data
-		out, err := yaml.Marshal(obj)
-		if err != nil {
-			return nil, err
-		}
-		if !firstObj {
-			_, err = buf.WriteString("---\n")
-			if err != nil {
-				return nil, err
-			}
-		}
-		_, err = buf.Write(out)
-		if err != nil {
-			return nil, err
-		}
-		firstObj = false
-	}
-	return buf.Bytes(), nil
-}
-
-// WriteToDir write each object in ResourceCollection to a file named with GroupVersionKindName.
-func WriteToDir(in resource.ResourceCollection, dirName string, printer Printer) (*Directory, error) {
-	dir, err := CreateDirectory(dirName)
-	if err != nil {
-		return &Directory{}, err
-	}
-
-	for gvkn, obj := range in {
-		f, err := dir.NewFile(gvkn.String())
-		if err != nil {
-			return &Directory{}, err
-		}
-		defer f.Close()
-		err = printer.Print(obj.Data, f)
-		if err != nil {
-			return &Directory{}, err
-		}
-	}
-	return dir, nil
-}