List of strategic merge patches (#637)

* support List of strategic merge patches

* add test for List of patches

* handle List in SliceFromBytes

* add test for List of patches with anchor/reference

* reorganize kunstruct validate

k8sdeps/kunstruct/factory.go

@@ -101,12 +101,16 @@ func (kf *KunstructuredFactoryImpl) Set(fs fs.FileSystem, ldr ifc.Loader) {
 }
 
 // validate validates that u has kind and name
+// except for kind `List`, which doesn't require a name
 func (kf *KunstructuredFactoryImpl) validate(u unstructured.Unstructured) error {
+	kind := u.GetKind()
+	if kind == "" {
+		return fmt.Errorf("missing kind in object %v", u)
+	} else if kind == "List" {
+		return nil
+	}
 	if u.GetName() == "" {
 		return fmt.Errorf("missing metadata.name in object %v", u)
 	}
-	if u.GetKind() == "" {
-		return fmt.Errorf("missing kind in object %v", u)
-	}
 	return nil
 }

k8sdeps/kunstruct/factory_test.go

@@ -33,6 +33,15 @@ func TestSliceFromBytes(t *testing.T) {
 				"name": "winnie",
 			},
 		})
+	testList := factory.FromMap(
+		map[string]interface{}{
+			"apiVersion": "v1",
+			"kind":       "List",
+			"items": []interface{}{
+				testConfigMap.Map(),
+				testConfigMap.Map(),
+			},
+		})
 
 	tests := []struct {
 		name        string
@@ -112,6 +121,24 @@ metadata:
 			expectedOut: nil,
 			expectedErr: true,
 		},
+		{
+			name: "List",
+			input: []byte(`
+apiVersion: v1
+kind: List
+items:
+- apiVersion: v1
+  kind: ConfigMap
+  metadata:
+    name: winnie
+- apiVersion: v1
+  kind: ConfigMap
+  metadata:
+    name: winnie
+`),
+			expectedOut: []ifc.Kunstructured{testList},
+			expectedErr: false,
+		},
 	}
 
 	for _, test := range tests {

pkg/resource/factory.go

@@ -17,6 +17,8 @@ limitations under the License.
 package resource
 
 import (
+	"encoding/json"
+	"fmt"
 	"log"
 
 	"sigs.k8s.io/kustomize/pkg/fs"
@@ -78,8 +80,30 @@ func (rf *Factory) SliceFromBytes(in []byte) ([]*Resource, error) {
 		return nil, err
 	}
 	var result []*Resource
-	for _, u := range kunStructs {
-		result = append(result, rf.FromKunstructured(u))
+	for len(kunStructs) > 0 {
+		u := kunStructs[0]
+		kunStructs = kunStructs[1:]
+		if u.GetKind() == "List" {
+			items := u.Map()["items"]
+			itemsSlice, ok := items.([]interface{})
+			if !ok {
+				return nil, fmt.Errorf("items in List is type %T, expected array.", items)
+			}
+			for _, item := range itemsSlice {
+				itemJSON, err := json.Marshal(item)
+				if err != nil {
+					return nil, err
+				}
+				innerU, err := rf.kf.SliceFromBytes(itemJSON)
+				if err != nil {
+					return nil, err
+				}
+				// append innerU to kunStructs so nested Lists can be handled
+				kunStructs = append(kunStructs, innerU...)
+			}
+		} else {
+			result = append(result, rf.FromKunstructured(u))
+		}
 	}
 	return result, nil
 }

pkg/resource/factory_test.go

@@ -49,10 +49,82 @@ metadata:
 	patch3 := `
 WOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOT: woot
 `
+	patchList := patch.StrategicMerge("patch4.yaml")
+	patch4 := `
+apiVersion: v1
+kind: List
+items:
+- apiVersion: apps/v1
+  kind: Deployment
+  metadata:
+    name: pooh
+- apiVersion: v1
+  kind: ConfigMap
+  metadata:
+    name: winnie
+    namespace: hundred-acre-wood
+`
+	patchList2 := patch.StrategicMerge("patch5.yaml")
+	patch5 := `
+apiVersion: v1
+kind: List
+items:
+- apiVersion: apps/v1
+  kind: Deployment
+  metadata:
+    name: deployment-a
+  spec: &hostAliases
+    template:
+      spec:
+        hostAliases:
+        - hostnames:
+          - a.example.com
+          ip: 8.8.8.8
+- apiVersion: apps/v1
+  kind: Deployment
+  metadata:
+    name: deployment-b
+  spec:
+    <<: *hostAliases
+`
+	testDeploymentSpec := map[string]interface{}{
+		"template": map[string]interface{}{
+			"spec": map[string]interface{}{
+				"hostAliases": []interface{}{
+					map[string]interface{}{
+						"hostnames": []interface{}{
+							"a.example.com",
+						},
+						"ip": "8.8.8.8",
+					},
+				},
+			},
+		},
+	}
+	testDeploymentA := factory.FromMap(
+		map[string]interface{}{
+			"apiVersion": "apps/v1",
+			"kind":       "Deployment",
+			"metadata": map[string]interface{}{
+				"name": "deployment-a",
+			},
+			"spec": testDeploymentSpec,
+		})
+	testDeploymentB := factory.FromMap(
+		map[string]interface{}{
+			"apiVersion": "apps/v1",
+			"kind":       "Deployment",
+			"metadata": map[string]interface{}{
+				"name": "deployment-b",
+			},
+			"spec": testDeploymentSpec,
+		})
 	l := loadertest.NewFakeLoader("/")
 	l.AddFile("/"+string(patchGood1), []byte(patch1))
 	l.AddFile("/"+string(patchGood2), []byte(patch2))
 	l.AddFile("/"+string(patchBad), []byte(patch3))
+	l.AddFile("/"+string(patchList), []byte(patch4))
+	l.AddFile("/"+string(patchList2), []byte(patch5))
 
 	tests := []struct {
 		name        string
@@ -78,6 +150,18 @@ WOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOT: woot
 			expectedOut: []*Resource{},
 			expectedErr: true,
 		},
+		{
+			name:        "listOfPatches",
+			input:       []patch.StrategicMerge{patchList},
+			expectedOut: []*Resource{testDeployment, testConfigMap},
+			expectedErr: false,
+		},
+		{
+			name:        "listWithAnchorReference",
+			input:       []patch.StrategicMerge{patchList2},
+			expectedOut: []*Resource{testDeploymentA, testDeploymentB},
+			expectedErr: false,
+		},
 	}
 	for _, test := range tests {
 		rs, err := factory.SliceFromPatches(l, test.input)