Adds helper functions for apply grouping objects

cmd/kubectl/go.mod

@@ -4,6 +4,8 @@ go 1.13
 
 require (
 	github.com/spf13/cobra v0.0.5
+	k8s.io/api v0.17.0
+	k8s.io/apimachinery v0.17.0
 	k8s.io/cli-runtime v0.17.0
 	k8s.io/client-go v0.17.0
 	k8s.io/component-base v0.17.0 // indirect

cmd/kubectl/kubectlcobra/grouping.go

@@ -0,0 +1,59 @@
+// Copyright 2020 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+// package kubectlcobra contains cobra commands from kubectl
+package kubectlcobra
+
+import (
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/cli-runtime/pkg/resource"
+)
+
+const GroupingLabel = "kustomize.k8s.io/group-id"
+
+// isGroupingObject returns true if the passed object has the
+// grouping label.
+// TODO(seans3): Check type is ConfigMap.
+func isGroupingObject(obj runtime.Object) bool {
+	if obj == nil {
+		return false
+	}
+	accessor, err := meta.Accessor(obj)
+	if err == nil {
+		labels := accessor.GetLabels()
+		_, exists := labels[GroupingLabel]
+		if exists {
+			return true
+		}
+	}
+	return false
+}
+
+// findGroupingObject returns the "Grouping" object (ConfigMap with
+// grouping label) if it exists, and a boolean describing if it was found.
+func findGroupingObject(infos []*resource.Info) (*resource.Info, bool) {
+	for _, info := range infos {
+		if info != nil && isGroupingObject(info.Object) {
+			return info, true
+		}
+	}
+	return nil, false
+}
+
+// sortGroupingObject reorders the infos slice to place the grouping
+// object in the first position. Returns true if grouping object found,
+// false otherwise.
+func sortGroupingObject(infos []*resource.Info) bool {
+	for i, info := range infos {
+		if info != nil && isGroupingObject(info.Object) {
+			// If the grouping object is not already in the first position,
+			// swap the grouping object with the first object.
+			if i > 0 {
+				infos[0], infos[i] = infos[i], infos[0]
+			}
+			return true
+		}
+	}
+	return false
+}

cmd/kubectl/kubectlcobra/grouping_test.go

@@ -0,0 +1,217 @@
+// Copyright 2020 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+// package kubectlcobra contains cobra commands from kubectl
+package kubectlcobra
+
+import (
+	"testing"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/cli-runtime/pkg/resource"
+)
+
+var testNamespace = "test-grouping-namespace"
+var groupingObjName = "test-grouping-obj"
+var pod1Name = "pod-1"
+var pod2Name = "pod-2"
+var pod3Name = "pod-3"
+
+var groupingObj = corev1.ConfigMap{
+	ObjectMeta: metav1.ObjectMeta{
+		Namespace: testNamespace,
+		Name:      groupingObjName,
+		Labels: map[string]string{
+			GroupingLabel: "true",
+		},
+	},
+}
+
+var groupingInfo = &resource.Info{
+	Namespace: testNamespace,
+	Name:      groupingObjName,
+	Object:    &groupingObj,
+}
+
+var pod1 = corev1.Pod{
+	ObjectMeta: metav1.ObjectMeta{
+		Namespace: testNamespace,
+		Name:      pod1Name,
+	},
+}
+
+var pod1Info = &resource.Info{
+	Namespace: testNamespace,
+	Name:      pod1Name,
+	Object:    &pod1,
+}
+
+var pod2 = corev1.Pod{
+	ObjectMeta: metav1.ObjectMeta{
+		Namespace: testNamespace,
+		Name:      pod2Name,
+	},
+}
+
+var pod2Info = &resource.Info{
+	Namespace: testNamespace,
+	Name:      pod2Name,
+	Object:    &pod2,
+}
+
+var pod3 = corev1.Pod{
+	ObjectMeta: metav1.ObjectMeta{
+		Namespace: testNamespace,
+		Name:      pod3Name,
+	},
+}
+
+var pod3Info = &resource.Info{
+	Namespace: testNamespace,
+	Name:      pod3Name,
+	Object:    &pod3,
+}
+
+func TestIsGroupingObject(t *testing.T) {
+	tests := []struct {
+		obj        runtime.Object
+		isGrouping bool
+	}{
+		{
+			obj:        nil,
+			isGrouping: false,
+		},
+		{
+			obj:        &groupingObj,
+			isGrouping: true,
+		},
+		{
+			obj:        &pod2,
+			isGrouping: false,
+		},
+	}
+
+	for _, test := range tests {
+		grouping := isGroupingObject(test.obj)
+		if test.isGrouping && !grouping {
+			t.Errorf("Grouping object not identified: %#v", test.obj)
+		}
+		if !test.isGrouping && grouping {
+			t.Errorf("Non-grouping object identifed as grouping obj: %#v", test.obj)
+		}
+	}
+}
+
+func TestFindGroupingObject(t *testing.T) {
+	tests := []struct {
+		infos  []*resource.Info
+		exists bool
+		name   string
+	}{
+		{
+			infos:  []*resource.Info{},
+			exists: false,
+			name:   "",
+		},
+		{
+			infos:  []*resource.Info{nil},
+			exists: false,
+			name:   "",
+		},
+		{
+			infos:  []*resource.Info{groupingInfo},
+			exists: true,
+			name:   groupingObjName,
+		},
+		{
+			infos:  []*resource.Info{pod1Info},
+			exists: false,
+			name:   "",
+		},
+		{
+			infos:  []*resource.Info{pod1Info, pod2Info, pod3Info},
+			exists: false,
+			name:   "",
+		},
+		{
+			infos:  []*resource.Info{pod1Info, pod2Info, groupingInfo, pod3Info},
+			exists: true,
+			name:   groupingObjName,
+		},
+	}
+
+	for _, test := range tests {
+		groupingObj, found := findGroupingObject(test.infos)
+		if test.exists && !found {
+			t.Errorf("Should have found grouping object")
+		}
+		if !test.exists && found {
+			t.Errorf("Grouping object found, but it does not exist: %#v", groupingObj)
+		}
+		if test.exists && found && test.name != groupingObj.Name {
+			t.Errorf("Grouping object name does not match: %s/%s", test.name, groupingObj.Name)
+		}
+	}
+}
+
+func TestSortGroupingObject(t *testing.T) {
+	tests := []struct {
+		infos  []*resource.Info
+		sorted bool
+	}{
+		{
+			infos:  []*resource.Info{},
+			sorted: false,
+		},
+		{
+			infos:  []*resource.Info{groupingInfo},
+			sorted: true,
+		},
+		{
+			infos:  []*resource.Info{pod1Info},
+			sorted: false,
+		},
+		{
+			infos:  []*resource.Info{pod1Info, pod2Info},
+			sorted: false,
+		},
+		{
+			infos:  []*resource.Info{groupingInfo, pod1Info},
+			sorted: true,
+		},
+		{
+			infos:  []*resource.Info{pod1Info, groupingInfo},
+			sorted: true,
+		},
+		{
+			infos:  []*resource.Info{pod1Info, pod2Info, groupingInfo, pod3Info},
+			sorted: true,
+		},
+		{
+			infos:  []*resource.Info{pod1Info, pod2Info, pod3Info, groupingInfo},
+			sorted: true,
+		},
+		{
+			infos:  []*resource.Info{groupingInfo, pod1Info, pod2Info, pod3Info},
+			sorted: true,
+		},
+	}
+
+	for _, test := range tests {
+		wasSorted := sortGroupingObject(test.infos)
+		if wasSorted && !test.sorted {
+			t.Errorf("Grouping object was sorted, but it shouldn't have been")
+		}
+		if !wasSorted && test.sorted {
+			t.Errorf("Grouping object was NOT sorted, but it should have been")
+		}
+		if wasSorted {
+			first := test.infos[0]
+			if !isGroupingObject(first.Object) {
+				t.Errorf("Grouping object was not sorted into first position")
+			}
+		}
+	}
+}