generate configmap for pruning

k8sdeps/transformer/factory.go

@@ -20,8 +20,10 @@ package transformer
 import (
 	"sigs.k8s.io/kustomize/k8sdeps/transformer/hash"
 	"sigs.k8s.io/kustomize/k8sdeps/transformer/patch"
+	"sigs.k8s.io/kustomize/k8sdeps/transformer/prune"
 	"sigs.k8s.io/kustomize/pkg/resource"
 	"sigs.k8s.io/kustomize/pkg/transformers"
+	"sigs.k8s.io/kustomize/pkg/types"
 )
 
 // FactoryImpl makes patch transformer and name hash transformer
@@ -41,3 +43,7 @@ func (p *FactoryImpl) MakePatchTransformer(slice []*resource.Resource, rf *resou
 func (p *FactoryImpl) MakeHashTransformer() transformers.Transformer {
 	return hash.NewNameHashTransformer()
 }
+
+func (p *FactoryImpl) MakePruneTransformer(arg *types.Prune, namespace string, append bool) transformers.Transformer {
+	return prune.NewPruneTransformer(arg, namespace, append)
+}

k8sdeps/transformer/hash/hash.go

@@ -20,6 +20,7 @@ import (
 	"crypto/sha256"
 	"encoding/json"
 	"fmt"
+	"sort"
 
 	"k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -86,6 +87,21 @@ func SecretHash(sec *v1.Secret) (string, error) {
 	return h, nil
 }
 
+// SortArrayAndComputeHash sorts a string array and
+// returns a hash for it
+func SortArrayAndComputeHash(s []string) (string, error) {
+	sort.Strings(s)
+	data, err := json.Marshal(s)
+	if err != nil {
+		return "", err
+	}
+	h, err := encodeHash(hash(string(data)))
+	if err != nil {
+		return "", err
+	}
+	return h, nil
+}
+
 // encodeConfigMap encodes a ConfigMap.
 // Data, Kind, and Name are taken into account.
 func encodeConfigMap(cm *v1.ConfigMap) (string, error) {

k8sdeps/transformer/hash/hash_test.go

@@ -90,6 +90,28 @@ func TestSecretHash(t *testing.T) {
 	}
 }
 
+func TestArrayHash(t *testing.T) {
+	array1 := []string{"a", "b", "c"}
+	array2 := []string{"c", "b", "a"}
+	h1, err := SortArrayAndComputeHash(array1)
+	if err != nil {
+		t.Errorf("unexpected error %v", err)
+	}
+	if h1 == "" {
+		t.Errorf("failed to hash %v", array1)
+	}
+	h2, err := SortArrayAndComputeHash(array2)
+	if err != nil {
+		t.Errorf("unexpected error %v", err)
+	}
+	if h2 == "" {
+		t.Errorf("failed to hash %v", array2)
+	}
+	if h1 != h2 {
+		t.Errorf("hash is not consistent with reordered list: %s %s", h1, h2)
+	}
+}
+
 func TestEncodeConfigMap(t *testing.T) {
 	cases := []struct {
 		desc   string

k8sdeps/transformer/prune/prune.go

@@ -0,0 +1,110 @@
+/*
+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 prune
+
+import (
+	"fmt"
+	"sigs.k8s.io/kustomize/k8sdeps/kunstruct"
+	"sigs.k8s.io/kustomize/k8sdeps/transformer/hash"
+	"sigs.k8s.io/kustomize/pkg/gvk"
+	"sigs.k8s.io/kustomize/pkg/resid"
+	"sigs.k8s.io/kustomize/pkg/resmap"
+	"sigs.k8s.io/kustomize/pkg/resource"
+	"sigs.k8s.io/kustomize/pkg/transformers"
+	"sigs.k8s.io/kustomize/pkg/types"
+)
+
+//const PruneAnnotation = "kustomize.k8s.io/PruneRevision"
+const PruneAnnotation = "current"
+
+// pruneTransformer compute the ConfigMap used in prune
+type pruneTransformer struct {
+	append      bool
+	cmName      string
+	cmNamespace string
+}
+
+var _ transformers.Transformer = &pruneTransformer{}
+
+// NewPruneTransformer makes a pruneTransformer.
+func NewPruneTransformer(p *types.Prune, namespace string, append bool) transformers.Transformer {
+	if p == nil || p.Type != "alphaConfigMap" || p.AlphaConfigMap.Namespace != namespace {
+		return transformers.NewNoOpTransformer()
+	}
+	return &pruneTransformer{
+		append:      append,
+		cmName:      p.AlphaConfigMap.Name,
+		cmNamespace: p.AlphaConfigMap.Namespace,
+	}
+}
+
+// Transform generates a prune ConfigMap based on the input ResMap.
+// this tranformer doesn't change existing resources -
+// it just visits resources and accumulates information to make a new ConfigMap.
+// The prune ConfigMap is used to support the pruning command in the client side tool,
+// which is proposed in https://github.com/kubernetes/enhancements/pull/810
+func (o *pruneTransformer) Transform(m resmap.ResMap) error {
+	keys := []string{}
+	for id, r := range m {
+		s := id.PruneString()
+		keys = append(keys, s)
+		for _, refid := range r.GetRefBy() {
+			keys = append(keys, s+"---"+refid.PruneString())
+		}
+	}
+	h, err := hash.SortArrayAndComputeHash(keys)
+	if err != nil {
+		return err
+	}
+
+	args := &types.ConfigMapArgs{}
+	args.Name = o.cmName
+	args.Namespace = o.cmNamespace
+	for _, key := range keys {
+		args.LiteralSources = append(args.LiteralSources,
+			key+"="+h)
+	}
+	opts := &types.GeneratorOptions{
+		Annotations: make(map[string]string),
+	}
+	opts.Annotations[PruneAnnotation] = h
+
+	kf := kunstruct.NewKunstructuredFactoryImpl()
+	k, err := kf.MakeConfigMap(nil, opts, args)
+	if err != nil {
+		return err
+	}
+
+	if !o.append {
+		for k := range m {
+			delete(m, k)
+		}
+	}
+
+	id := resid.NewResIdWithPrefixNamespace(
+		gvk.Gvk{
+			Version: "v1",
+			Kind:    "ConfigMap",
+		},
+		o.cmName,
+		"", o.cmNamespace)
+	if _, ok := m[id]; ok {
+		return fmt.Errorf("id %v is already used, please use a different name in the prune field", id)
+	}
+	m[id] = resource.NewFactory(kf).FromKunstructured(k)
+	return nil
+}

k8sdeps/transformer/prune/prune_test.go

@@ -0,0 +1,171 @@
+/*
+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 prune
+
+import (
+	"reflect"
+	"testing"
+
+	"sigs.k8s.io/kustomize/k8sdeps/kunstruct"
+	"sigs.k8s.io/kustomize/pkg/gvk"
+	"sigs.k8s.io/kustomize/pkg/resid"
+	"sigs.k8s.io/kustomize/pkg/resmap"
+	"sigs.k8s.io/kustomize/pkg/resource"
+	"sigs.k8s.io/kustomize/pkg/types"
+)
+
+var secret = gvk.Gvk{Version: "v1", Kind: "Secret"}
+var cmap = gvk.Gvk{Version: "v1", Kind: "ConfigMap"}
+var deploy = gvk.Gvk{Group: "apps", Version: "v1", Kind: "Deployment"}
+
+func makeResMap() resmap.ResMap {
+	rf := resource.NewFactory(
+		kunstruct.NewKunstructuredFactoryImpl())
+	objs := resmap.ResMap{
+		resid.NewResId(cmap, "cm1"): rf.FromMap(
+			map[string]interface{}{
+				"apiVersion": "v1",
+				"kind":       "ConfigMap",
+				"metadata": map[string]interface{}{
+					"name": "cm1",
+				},
+			}),
+		resid.NewResId(secret, "secret1"): rf.FromMap(
+			map[string]interface{}{
+				"apiVersion": "v1",
+				"kind":       "Secret",
+				"metadata": map[string]interface{}{
+					"name": "secret1",
+				},
+			}),
+		resid.NewResId(deploy, "deploy1"): rf.FromMap(
+			map[string]interface{}{
+				"group":      "apps",
+				"apiVersion": "v1",
+				"kind":       "Deployment",
+				"metadata": map[string]interface{}{
+					"name": "deploy1",
+				},
+				"spec": map[string]interface{}{
+					"template": map[string]interface{}{
+						"spec": map[string]interface{}{
+							"containers": []interface{}{
+								map[string]interface{}{
+									"name":  "nginx",
+									"image": "nginx:1.7.9",
+									"env": []interface{}{
+										map[string]interface{}{
+											"name": "CM_FOO",
+											"valueFrom": map[string]interface{}{
+												"configMapKeyRef": map[string]interface{}{
+													"name": "cm1",
+													"key":  "somekey",
+												},
+											},
+										},
+									},
+									"envFrom": []interface{}{
+										map[string]interface{}{
+											"configMapRef": map[string]interface{}{
+												"name": "cm1",
+												"key":  "somekey",
+											},
+										},
+										map[string]interface{}{
+											"secretRef": map[string]interface{}{
+												"name": "secret1",
+												"key":  "somekey",
+											},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			}),
+	}
+	objs[resid.NewResId(cmap, "cm1")].AppendRefBy(resid.NewResId(deploy, "deploy1"))
+	objs[resid.NewResId(secret, "secret1")].AppendRefBy(resid.NewResId(deploy, "deploy1"))
+	return objs
+}
+
+func TestPruneTransformer(t *testing.T) {
+	rf := resource.NewFactory(
+		kunstruct.NewKunstructuredFactoryImpl())
+
+	// hash is derived based on all keys in the ConfigMap data field.
+	// It is added to annotations as
+	//   current: hash
+	// When seeing the same annotation, prune binary assumes no
+	// clean up is needed
+	hash := "k777d7h45b"
+	//  This is the root or inventory object which tracks all
+	// the applied resources - this is the thing we expect the transformer to create.
+	pruneMap := rf.FromMap(
+		map[string]interface{}{
+			"apiVersion": "v1",
+			"kind":       "ConfigMap",
+			"metadata": map[string]interface{}{
+				"name":      "pruneCM",
+				"namespace": "default",
+				"annotations": map[string]interface{}{
+					"current": hash,
+				},
+			},
+			"data": map[string]interface{}{
+				"_ConfigMap__cm1":                             hash,
+				"_Secret__secret1":                            hash,
+				"apps_Deployment__deploy1":                    hash,
+				"_ConfigMap__cm1---apps_Deployment__deploy1":  hash,
+				"_Secret__secret1---apps_Deployment__deploy1": hash,
+			},
+		})
+	expected := resmap.ResMap{
+		resid.NewResIdWithPrefixNamespace(cmap, "pruneCM", "", "default"): pruneMap,
+	}
+
+	p := &types.Prune{
+		Type: "alphaConfigMap",
+		AlphaConfigMap: types.NameArgs{
+			Name:      "pruneCM",
+			Namespace: "default",
+		},
+	}
+	objs := makeResMap()
+
+	// include the original resmap; only return the ConfigMap for pruning
+	tran := NewPruneTransformer(p, "default", false)
+	tran.Transform(objs)
+
+	if !reflect.DeepEqual(objs, expected) {
+		err := expected.ErrorIfNotEqual(objs)
+		t.Fatalf("actual doesn't match expected: %v", err)
+	}
+
+	objs = makeResMap()
+	expected = objs.DeepCopy(rf)
+	expected[resid.NewResIdWithPrefixNamespace(cmap, "pruneCM", "", "default")] = pruneMap
+	// append the ConfigMap for pruning to the original resmap
+	tran = NewPruneTransformer(p, "default", true)
+	tran.Transform(objs)
+
+	if !reflect.DeepEqual(objs, expected) {
+		err := expected.ErrorIfNotEqual(objs)
+		t.Fatalf("actual doesn't match expected: %v", err)
+	}
+}