Support for source and sink with functions

cmd/config/configcobra/cmds.go

@@ -80,6 +80,8 @@ func NewConfigCommand(name string) *cobra.Command {
 	root.AddCommand(commands.SetCommand(name))
 	root.AddCommand(commands.ListSettersCommand(name))
 	root.AddCommand(commands.CreateSetterCommand(name))
+	root.AddCommand(commands.SinkCommand(name))
+	root.AddCommand(commands.SourceCommand(name))
 
 	root.AddCommand(&cobra.Command{
 		Use:   "docs-merge",

cmd/config/docs/commands/sink.md

@@ -0,0 +1,18 @@
+## sink
+
+[Alpha] Implement a Sink by writing input to a local directory.
+
+### Synopsis
+
+[Alpha] Implement a Sink by writing input to a local directory.
+
+    kustomize config sink DIR
+
+  DIR:
+    Path to local directory.
+
+`sink` writes its input to a directory
+
+### Examples
+
+    kustomize config source DIR/ | your-function | kustomize config sink DIR/

cmd/config/docs/commands/source.md

@@ -0,0 +1,21 @@
+## source
+
+[Alpha] Implement a Source by reading a local directory.
+
+### Synopsis
+
+[Alpha] Implement a Source by reading a local directory.
+
+    kustomize config source DIR
+
+  DIR:
+    Path to local directory.
+
+`source` emits configuration to act as input to a function
+
+### Examples
+
+    # emity configuration directory as input source to a function
+    kustomize config source DIR/
+
+    kustomize config source DIR/ | your-function | kustomize config sink DIR/

cmd/config/internal/commands/sink.go

@@ -0,0 +1,48 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package commands
+
+import (
+	"github.com/spf13/cobra"
+	"sigs.k8s.io/kustomize/cmd/config/internal/generateddocs/commands"
+	"sigs.k8s.io/kustomize/kyaml/kio"
+)
+
+// GetSinkRunner returns a command for Sink.
+func GetSinkRunner(name string) *SinkRunner {
+	r := &SinkRunner{}
+	c := &cobra.Command{
+		Use:     "sink DIR",
+		Short:   commands.SinkShort,
+		Long:    commands.SinkLong,
+		Example: commands.SinkExamples,
+		RunE:    r.runE,
+		Args:    cobra.ExactArgs(1),
+	}
+	fixDocs(name, c)
+	r.Command = c
+	return r
+}
+
+func SinkCommand(name string) *cobra.Command {
+	return GetSinkRunner(name).Command
+}
+
+// SinkRunner contains the run function
+type SinkRunner struct {
+	Command *cobra.Command
+}
+
+func (r *SinkRunner) runE(c *cobra.Command, args []string) error {
+	err := kio.Pipeline{
+		Inputs: []kio.Reader{&kio.ByteReader{Reader: c.InOrStdin()}},
+		Outputs: []kio.Writer{
+			&kio.LocalPackageWriter{
+				PackagePath:      args[0],
+				ClearAnnotations: []string{"config.kubernetes.io/path"},
+			},
+		},
+	}.Execute()
+	return handleError(c, err)
+}

cmd/config/internal/commands/sink_test.go

@@ -0,0 +1,140 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package commands_test
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"sigs.k8s.io/kustomize/cmd/config/internal/commands"
+)
+
+func TestSinkCommand(t *testing.T) {
+	d, err := ioutil.TempDir("", "kustomize-source-test")
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+	defer os.RemoveAll(d)
+
+	// fmt the files
+	b := &bytes.Buffer{}
+	r := commands.GetSinkRunner("")
+	r.Command.SetIn(bytes.NewBufferString(`apiVersion: config.kubernetes.io/v1alpha1
+kind: ResourceList
+items:
+- kind: Deployment
+  metadata:
+    labels:
+      app: nginx2
+    name: foo
+    annotations:
+      app: nginx2
+      config.kubernetes.io/index: '0'
+      config.kubernetes.io/path: 'f1.yaml'
+  spec:
+    replicas: 1
+- kind: Service
+  metadata:
+    name: foo
+    annotations:
+      app: nginx
+      config.kubernetes.io/index: '1'
+      config.kubernetes.io/path: 'f1.yaml'
+  spec:
+    selector:
+      app: nginx
+- apiVersion: v1
+  kind: Abstraction
+  metadata:
+    name: foo
+    annotations:
+      config.kubernetes.io/function: |
+        container:
+          image: gcr.io/example/reconciler:v1
+      config.kubernetes.io/local-config: "true"
+      config.kubernetes.io/index: '0'
+      config.kubernetes.io/path: 'f2.yaml'
+  spec:
+    replicas: 3
+- apiVersion: apps/v1
+  kind: Deployment
+  metadata:
+    labels:
+      app: nginx
+    name: bar
+    annotations:
+      app: nginx
+      config.kubernetes.io/index: '1'
+      config.kubernetes.io/path: 'f2.yaml'
+  spec:
+    replicas: 3
+`))
+	r.Command.SetArgs([]string{d})
+	r.Command.SetOut(b)
+	if !assert.NoError(t, r.Command.Execute()) {
+		t.FailNow()
+	}
+
+	actual, err := ioutil.ReadFile(filepath.Join(d, "f1.yaml"))
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+	expected := `kind: Deployment
+metadata:
+  labels:
+    app: nginx2
+  name: foo
+  annotations:
+    app: nginx2
+spec:
+  replicas: 1
+---
+kind: Service
+metadata:
+  name: foo
+  annotations:
+    app: nginx
+spec:
+  selector:
+    app: nginx
+`
+	if !assert.Equal(t, expected, string(actual)) {
+		t.FailNow()
+	}
+
+	actual, err = ioutil.ReadFile(filepath.Join(d, "f2.yaml"))
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+	expected = `apiVersion: v1
+kind: Abstraction
+metadata:
+  name: foo
+  annotations:
+    config.kubernetes.io/function: |
+      container:
+        image: gcr.io/example/reconciler:v1
+    config.kubernetes.io/local-config: "true"
+spec:
+  replicas: 3
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  labels:
+    app: nginx
+  name: bar
+  annotations:
+    app: nginx
+spec:
+  replicas: 3
+`
+	if !assert.Equal(t, expected, string(actual)) {
+		t.FailNow()
+	}
+}

cmd/config/internal/commands/source.go

@@ -0,0 +1,77 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package commands
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"sigs.k8s.io/kustomize/cmd/config/internal/generateddocs/commands"
+	"sigs.k8s.io/kustomize/kyaml/kio"
+	"sigs.k8s.io/kustomize/kyaml/yaml"
+)
+
+// GetSourceRunner returns a command for Source.
+func GetSourceRunner(name string) *SourceRunner {
+	r := &SourceRunner{}
+	c := &cobra.Command{
+		Use:     "source DIR",
+		Short:   commands.SourceShort,
+		Long:    commands.SourceLong,
+		Example: commands.SourceExamples,
+		RunE:    r.runE,
+		Args:    cobra.ExactArgs(1),
+	}
+	fixDocs(name, c)
+	c.Flags().StringVar(&r.WrapKind, "wrap-kind", kio.ResourceListKind,
+		"output using this format.")
+	c.Flags().StringVar(&r.WrapApiVersion, "wrap-version", kio.ResourceListAPIVersion,
+		"output using this format.")
+	c.Flags().StringVar(&r.FunctionConfig, "function-config", "",
+		"path to function config.")
+	r.Command = c
+	_ = c.MarkFlagFilename("function-config", "yaml", "json", "yml")
+	return r
+}
+
+func SourceCommand(name string) *cobra.Command {
+	return GetSourceRunner(name).Command
+}
+
+// SourceRunner contains the run function
+type SourceRunner struct {
+	WrapKind       string
+	WrapApiVersion string
+	FunctionConfig string
+	Command        *cobra.Command
+}
+
+func (r *SourceRunner) runE(c *cobra.Command, args []string) error {
+	// if there is a function-config specified, emit it
+	var functionConfig *yaml.RNode
+	if r.FunctionConfig != "" {
+		configs, err := kio.LocalPackageReader{PackagePath: r.FunctionConfig}.Read()
+		if err != nil {
+			return err
+		}
+		if len(configs) != 1 {
+			return fmt.Errorf("expected exactly 1 functionConfig, found %d", len(configs))
+		}
+		functionConfig = configs[0]
+	}
+
+	var outputs []kio.Writer
+	outputs = append(outputs, kio.ByteWriter{
+		Writer:                c.OutOrStdout(),
+		KeepReaderAnnotations: true,
+		WrappingKind:          r.WrapKind,
+		WrappingAPIVersion:    r.WrapApiVersion,
+		FunctionConfig:        functionConfig,
+	})
+
+	err := kio.Pipeline{
+		Inputs:  []kio.Reader{kio.LocalPackageReader{PackagePath: args[0]}},
+		Outputs: outputs}.Execute()
+	return handleError(c, err)
+}

cmd/config/internal/commands/source_test.go

@@ -0,0 +1,136 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package commands_test
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"sigs.k8s.io/kustomize/cmd/config/internal/commands"
+)
+
+func TestSourceCommand(t *testing.T) {
+	d, err := ioutil.TempDir("", "kustomize-source-test")
+	if !assert.NoError(t, err) {
+		return
+	}
+	defer os.RemoveAll(d)
+
+	err = ioutil.WriteFile(filepath.Join(d, "f1.yaml"), []byte(`
+kind: Deployment
+metadata:
+  labels:
+    app: nginx2
+  name: foo
+  annotations:
+    app: nginx2
+spec:
+  replicas: 1
+---
+kind: Service
+metadata:
+  name: foo
+  annotations:
+    app: nginx
+spec:
+  selector:
+    app: nginx
+`), 0600)
+	if !assert.NoError(t, err) {
+		return
+	}
+	err = ioutil.WriteFile(filepath.Join(d, "f2.yaml"), []byte(`
+apiVersion: v1
+kind: Abstraction
+metadata:
+  name: foo
+  annotations:
+    config.kubernetes.io/function: |
+      container:
+        image: gcr.io/example/reconciler:v1
+    config.kubernetes.io/local-config: "true"
+spec:
+  replicas: 3
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  labels:
+    app: nginx
+  name: bar
+  annotations:
+    app: nginx
+spec:
+  replicas: 3
+`), 0600)
+	if !assert.NoError(t, err) {
+		return
+	}
+
+	// fmt the files
+	b := &bytes.Buffer{}
+	r := commands.GetSourceRunner("")
+	r.Command.SetArgs([]string{d})
+	r.Command.SetOut(b)
+	if !assert.NoError(t, r.Command.Execute()) {
+		return
+	}
+
+	if !assert.Equal(t, `apiVersion: config.kubernetes.io/v1alpha1
+kind: ResourceList
+items:
+- kind: Deployment
+  metadata:
+    labels:
+      app: nginx2
+    name: foo
+    annotations:
+      app: nginx2
+      config.kubernetes.io/index: '0'
+      config.kubernetes.io/path: 'f1.yaml'
+  spec:
+    replicas: 1
+- kind: Service
+  metadata:
+    name: foo
+    annotations:
+      app: nginx
+      config.kubernetes.io/index: '1'
+      config.kubernetes.io/path: 'f1.yaml'
+  spec:
+    selector:
+      app: nginx
+- apiVersion: v1
+  kind: Abstraction
+  metadata:
+    name: foo
+    annotations:
+      config.kubernetes.io/function: |
+        container:
+          image: gcr.io/example/reconciler:v1
+      config.kubernetes.io/local-config: "true"
+      config.kubernetes.io/index: '0'
+      config.kubernetes.io/path: 'f2.yaml'
+  spec:
+    replicas: 3
+- apiVersion: apps/v1
+  kind: Deployment
+  metadata:
+    labels:
+      app: nginx
+    name: bar
+    annotations:
+      app: nginx
+      config.kubernetes.io/index: '1'
+      config.kubernetes.io/path: 'f2.yaml'
+  spec:
+    replicas: 3
+`, b.String()) {
+		return
+	}
+}

cmd/config/internal/generateddocs/commands/docs.go

@@ -332,6 +332,37 @@ var SetExamples = `
         name: test-app2 # {"description":"test environment","type":"string","x-kustomize":{"setBy":"dev","partialFieldSetters":[{"name":"name-prefix","value":"test"}]}}
     ...`
 
+var SinkShort = `[Alpha] Implement a Sink by writing input to a local directory.`
+var SinkLong = `
+[Alpha] Implement a Sink by writing input to a local directory.
+
+    kustomize config sink DIR
+
+  DIR:
+    Path to local directory.
+
+` + "`" + `sink` + "`" + ` writes its input to a directory
+`
+var SinkExamples = `
+    kustomize config source DIR/ | your-function | kustomize config sink DIR/`
+
+var SourceShort = `[Alpha] Implement a Source by reading a local directory.`
+var SourceLong = `
+[Alpha] Implement a Source by reading a local directory.
+
+    kustomize config source DIR
+
+  DIR:
+    Path to local directory.
+
+` + "`" + `source` + "`" + ` emits configuration to act as input to a function
+`
+var SourceExamples = `
+    # emity configuration directory as input source to a function
+    kustomize config source DIR/
+
+    kustomize config source DIR/ | your-function | kustomize config sink DIR/`
+
 var TreeShort = `[Alpha] Display Resource structure from a directory or stdin.`
 var TreeLong = `
 [Alpha] Display Resource structure from a directory or stdin.