[Feature] Compare Generic (#1480)

CHANGELOG.md

@@ -9,6 +9,7 @@
 - (Documentation) Do not use field type name for field URL hash
 - (Maintenance) Bump Go to 1.20.11
 - (Feature) License ArangoDeployment Fetcher
+- (Feature) K8S Resources Compare Generic
 
 ## [1.2.35](https://github.com/arangodb/kube-arangodb/tree/1.2.35) (2023-11-06)
 - (Maintenance) Update go-driver to v1.6.0, update IsNotFound() checks

pkg/apis/deployment/v1/arango_member_pod_template.go

@@ -63,13 +63,6 @@ type ArangoMemberPodTemplate struct {
 	Endpoint *string `json:"endpoint,omitempty"`
 }
 
-func (a *ArangoMemberPodTemplate) GetChecksum() string {
-	if a == nil {
-		return ""
-	}
-	return a.Checksum
-}
-
 func (a *ArangoMemberPodTemplate) Equals(b *ArangoMemberPodTemplate) bool {
 	if a == nil && b == nil {
 		return true
@@ -100,3 +93,45 @@ func (a *ArangoMemberPodTemplate) EqualPodSpecChecksum(checksum string) bool {
 	}
 	return checksum == a.PodSpecChecksum
 }
+
+func (a *ArangoMemberPodTemplate) GetTemplate() *core.PodTemplateSpec {
+	if a == nil {
+		return nil
+	}
+	return a.PodSpec.DeepCopy()
+}
+
+func (a *ArangoMemberPodTemplate) SetTemplate(t *core.PodTemplateSpec) {
+	if a == nil {
+		return
+	}
+	a.PodSpec = t.DeepCopy()
+}
+
+func (a *ArangoMemberPodTemplate) GetTemplateChecksum() string {
+	if a == nil {
+		return ""
+	}
+	return a.PodSpecChecksum
+}
+
+func (a *ArangoMemberPodTemplate) SetTemplateChecksum(s string) {
+	if a == nil {
+		return
+	}
+	a.PodSpecChecksum = s
+}
+
+func (a *ArangoMemberPodTemplate) SetChecksum(s string) {
+	if a == nil {
+		return
+	}
+	a.Checksum = s
+}
+
+func (a *ArangoMemberPodTemplate) GetChecksum() string {
+	if a == nil {
+		return ""
+	}
+	return a.Checksum
+}

pkg/deployment/reconcile/plan_builder_high.go

@@ -30,6 +30,7 @@ import (
 	"github.com/arangodb/kube-arangodb/pkg/deployment/actions"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/reconcile/shared"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/rotation"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
 )
 
@@ -231,7 +232,7 @@ func (r *Reconciler) updateMemberRotationConditions(apiObject k8sutil.APIObject,
 		return nil, err
 	} else {
 		switch m {
-		case rotation.EnforcedRotation:
+		case compare.EnforcedRotation:
 			if reason != "" {
 				r.log.Bool("enforced", true).Info(reason)
 			} else {
@@ -239,7 +240,7 @@ func (r *Reconciler) updateMemberRotationConditions(apiObject k8sutil.APIObject,
 			}
 			// We need to do enforced rotation
 			return restartMemberConditionAction(group, member.ID, reason), nil
-		case rotation.InPlaceRotation:
+		case compare.InPlaceRotation:
 			if member.Conditions.IsTrue(api.ConditionTypeUpdateFailed) {
 				if !(member.Conditions.IsTrue(api.ConditionTypePendingRestart) || member.Conditions.IsTrue(api.ConditionTypeRestart)) {
 					return api.Plan{pendingRestartMemberConditionAction(group, member.ID, reason)}, nil
@@ -249,11 +250,11 @@ func (r *Reconciler) updateMemberRotationConditions(apiObject k8sutil.APIObject,
 				return nil, nil
 			}
 			return api.Plan{shared.UpdateMemberConditionActionV2(reason, api.ConditionTypePendingUpdate, group, member.ID, true, reason, "", "")}, nil
-		case rotation.SilentRotation:
+		case compare.SilentRotation:
 			// Propagate changes without restart, but apply plan if required
 			plan = append(plan, actions.NewAction(api.ActionTypeArangoMemberUpdatePodStatus, group, member, "Propagating status of pod").AddParam(ActionTypeArangoMemberUpdatePodStatusChecksum, checksum))
 			return plan, nil
-		case rotation.GracefulRotation:
+		case compare.GracefulRotation:
 			if reason != "" {
 				r.log.Bool("enforced", false).Info(reason)
 			} else {

pkg/deployment/reconcile/plan_builder_rotate_upgrade.go

@@ -36,6 +36,7 @@ import (
 	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/rotation"
 	"github.com/arangodb/kube-arangodb/pkg/util"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
 )
 
@@ -213,7 +214,7 @@ func (r *Reconciler) createUpdatePlanInternal(apiObject k8sutil.APIObject, spec
 		if mode, p, checksum, reason, err := rotation.IsRotationRequired(context.ACS(), spec, m.Member, m.Group, p, arangoMember.Spec.Template, arangoMember.Status.Template); err != nil {
 			r.planLogger.Err(err).Str("member", m.Member.ID).Error("Error while generating update plan")
 			continue
-		} else if mode != rotation.InPlaceRotation {
+		} else if mode != compare.InPlaceRotation {
 			return api.Plan{
 				shared.RemoveMemberConditionActionV2(reason, api.ConditionTypePendingUpdate, m.Group, m.Member.ID),
 				shared.UpdateMemberConditionActionV2(reason, api.ConditionTypeUpdating, m.Group, m.Member.ID, true, reason, "", ""),

pkg/deployment/rotation/arangod.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -25,36 +25,37 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/util"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
-func podCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
-		if spec.SchedulerName != status.SchedulerName {
-			status.SchedulerName = spec.SchedulerName
-			mode = mode.And(SilentRotation)
+func podCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
+		if spec.Spec.SchedulerName != status.Spec.SchedulerName {
+			status.Spec.SchedulerName = spec.Spec.SchedulerName
+			mode = mode.And(compare.SilentRotation)
 		}
 
-		if !util.CompareInt64p(spec.TerminationGracePeriodSeconds, status.TerminationGracePeriodSeconds) {
-			status.TerminationGracePeriodSeconds = spec.TerminationGracePeriodSeconds
-			mode = mode.And(SilentRotation)
+		if !util.CompareInt64p(spec.Spec.TerminationGracePeriodSeconds, status.Spec.TerminationGracePeriodSeconds) {
+			status.Spec.TerminationGracePeriodSeconds = spec.Spec.TerminationGracePeriodSeconds
+			mode = mode.And(compare.SilentRotation)
 		}
 
 		return
 	}
 }
 
-func affinityCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, e error) {
-		if specC, err := util.SHA256FromJSON(spec.Affinity); err != nil {
+func affinityCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, e error) {
+		if specC, err := util.SHA256FromJSON(spec.Spec.Affinity); err != nil {
 			e = err
 			return
 		} else {
-			if statusC, err := util.SHA256FromJSON(status.Affinity); err != nil {
+			if statusC, err := util.SHA256FromJSON(status.Spec.Affinity); err != nil {
 				e = err
 				return
 			} else if specC != statusC {
-				mode = mode.And(SilentRotation)
-				status.Affinity = spec.Affinity.DeepCopy()
+				mode = mode.And(compare.SilentRotation)
+				status.Spec.Affinity = spec.Spec.Affinity.DeepCopy()
 				return
 			} else {
 				return

pkg/deployment/rotation/arangod_containers.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -30,8 +30,9 @@ import (
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/features"
 	"github.com/arangodb/kube-arangodb/pkg/util"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
-	strings2 "github.com/arangodb/kube-arangodb/pkg/util/strings"
+	arangoStrings "github.com/arangodb/kube-arangodb/pkg/util/strings"
 )
 
 const (
@@ -39,37 +40,36 @@ const (
 	ContainerImage = "image"
 )
 
-func containersCompare(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
-		a, b := spec.Containers, status.Containers
+func containersCompare(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return compare.SubElementsP2(func(in *core.PodTemplateSpec) *[]core.Container {
+		return &in.Spec.Containers
+	}, func(ds api.DeploymentSpec, g api.ServerGroup, specContainers, statusContainers *[]core.Container) compare.Func {
+		return compare.ArrayExtractorP2(func(ds api.DeploymentSpec, g api.ServerGroup, specContainer, statusContainer *core.Container) compare.Func {
+			return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
+				if specContainer.Name != statusContainer.Name {
+					return compare.SkippedRotation, nil, nil
+				}
 
-		if len(a) == 0 || len(a) != len(b) {
-			// If the number of the containers is different or is zero then skip rotation.
-			return SkippedRotation, nil, nil
-		}
-
-		for id := range a {
-			if ac, bc := &a[id], &b[id]; ac.Name == bc.Name {
-				if ac.Name == api.ServerGroupReservedContainerNameServer {
-					if isOnlyLogLevelChanged(ac.Command, bc.Command) {
+				if specContainer.Name == api.ServerGroupReservedContainerNameServer {
+					if isOnlyLogLevelChanged(specContainer.Command, statusContainer.Command) {
 						plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerArgsLogLevelUpdate).
-							AddParam(ContainerName, ac.Name))
+							AddParam(ContainerName, specContainer.Name))
 
-						bc.Command = ac.Command
-						mode = mode.And(InPlaceRotation)
+						statusContainer.Command = specContainer.Command
+						mode = mode.And(compare.InPlaceRotation)
 					}
 
-					g := podContainerFuncGenerator(ds, g, ac, bc)
+					g := compare.NewFuncGenP2(ds, g, specContainer, statusContainer)
 
-					if m, p, err := comparePodContainer(builder, g(compareServerContainerVolumeMounts), g(compareServerContainerProbes), g(compareServerContainerEnvs)); err != nil {
+					if m, p, err := compare.Evaluate(builder, g(compareServerContainerVolumeMounts), g(compareServerContainerProbes), g(compareServerContainerEnvs)); err != nil {
 						log.Err(err).Msg("Error while getting pod diff")
-						return SkippedRotation, nil, err
+						return compare.SkippedRotation, nil, err
 					} else {
 						mode = mode.And(m)
 						plan = append(plan, p...)
 					}
 
-					if !equality.Semantic.DeepEqual(ac.EnvFrom, bc.EnvFrom) {
+					if !equality.Semantic.DeepEqual(specContainer.EnvFrom, statusContainer.EnvFrom) {
 						// Check EnvFromSource differences.
 						filter := func(a, b map[string]core.EnvFromSource) (map[string]core.EnvFromSource, map[string]core.EnvFromSource) {
 							delete(a, features.ConfigMapName())
@@ -77,81 +77,81 @@ func containersCompare(ds api.DeploymentSpec, g api.ServerGroup, spec, status *c
 
 							return a, b
 						}
-						if areEnvsFromEqual(ac.EnvFrom, bc.EnvFrom, filter) {
+						if areEnvsFromEqual(specContainer.EnvFrom, statusContainer.EnvFrom, filter) {
 							// Envs are the same after filtering, but it were different before filtering, so it can be replaced.
-							bc.EnvFrom = ac.EnvFrom
-							mode = mode.And(SilentRotation)
+							statusContainer.EnvFrom = specContainer.EnvFrom
+							mode = mode.And(compare.SilentRotation)
 						}
 					}
 
-					if !equality.Semantic.DeepEqual(ac.Ports, bc.Ports) {
-						bc.Ports = ac.Ports
-						mode = mode.And(SilentRotation)
+					if !equality.Semantic.DeepEqual(specContainer.Ports, statusContainer.Ports) {
+						statusContainer.Ports = specContainer.Ports
+						mode = mode.And(compare.SilentRotation)
 					}
 				} else {
-					if ac.Image != bc.Image {
+					if specContainer.Image != statusContainer.Image {
 						// Image changed
-						plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerImageUpdate).AddParam(ContainerName, ac.Name).AddParam(ContainerImage, ac.Image))
+						plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerImageUpdate).AddParam(ContainerName, specContainer.Name).AddParam(ContainerImage, specContainer.Image))
 
-						bc.Image = ac.Image
-						mode = mode.And(InPlaceRotation)
+						statusContainer.Image = specContainer.Image
+						mode = mode.And(compare.InPlaceRotation)
 					}
 
-					g := podContainerFuncGenerator(ds, g, ac, bc)
+					g := compare.NewFuncGenP2(ds, g, specContainer, statusContainer)
 
-					if m, p, err := comparePodContainer(builder, g(compareAnyContainerVolumeMounts), g(compareAnyContainerEnvs)); err != nil {
+					if m, p, err := compare.Evaluate(builder, g(compareAnyContainerVolumeMounts), g(compareAnyContainerEnvs)); err != nil {
 						log.Err(err).Msg("Error while getting pod diff")
-						return SkippedRotation, nil, err
+						return compare.SkippedRotation, nil, err
 					} else {
 						mode = mode.And(m)
 						plan = append(plan, p...)
 					}
 				}
 
-				if api.IsReservedServerGroupContainerName(ac.Name) {
-					mode = mode.And(internalContainerLifecycleCompare(ac, bc))
+				if api.IsReservedServerGroupContainerName(specContainer.Name) {
+					mode = mode.And(internalContainerLifecycleCompare(specContainer, statusContainer))
 				}
-			}
-		}
 
-		return
-	}
+				return
+			}
+		})(ds, g, specContainers, statusContainers)
+	})(ds, g, spec, status)
 }
 
-func initContainersCompare(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (Mode, api.Plan, error) {
+func initContainersCompare(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return func(builder api.ActionBuilder) (compare.Mode, api.Plan, error) {
 		gs := deploymentSpec.GetServerGroupSpec(group)
 
-		equal, err := util.CompareJSON(spec.InitContainers, status.InitContainers)
+		equal, err := util.CompareJSON(spec.Spec.InitContainers, status.Spec.InitContainers)
 		if err != nil {
-			return SkippedRotation, nil, err
+			return compare.SkippedRotation, nil, err
 		}
 
 		// if equal nothing to do
 		if equal {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		switch gs.InitContainers.GetMode().Get() {
 		case api.ServerGroupInitContainerIgnoreMode:
 			// Just copy spec to status if different
 			if !equal {
-				status.InitContainers = spec.InitContainers
-				return SilentRotation, nil, err
+				status.Spec.InitContainers = spec.Spec.InitContainers
+				return compare.SilentRotation, nil, err
 			} else {
-				return SkippedRotation, nil, err
+				return compare.SkippedRotation, nil, err
 			}
 		default:
-			statusInitContainers, specInitContainers := filterReservedInitContainers(status.InitContainers), filterReservedInitContainers(spec.InitContainers)
+			statusInitContainers, specInitContainers := filterReservedInitContainers(status.Spec.InitContainers), filterReservedInitContainers(spec.Spec.InitContainers)
 			if equal, err := util.CompareJSON(specInitContainers, statusInitContainers); err != nil {
-				return SkippedRotation, nil, err
+				return compare.SkippedRotation, nil, err
 			} else if equal {
-				status.InitContainers = spec.InitContainers
-				return SilentRotation, nil, nil
+				status.Spec.InitContainers = spec.Spec.InitContainers
+				return compare.SilentRotation, nil, nil
 			}
 		}
 
-		return SkippedRotation, nil, nil
+		return compare.SkippedRotation, nil, nil
 	}
 }
 
@@ -173,7 +173,7 @@ func filterReservedInitContainers(c []core.Container) []core.Container {
 // isOnlyLogLevelChanged returns true when status and spec log level arguments are different.
 // If any other argument than --log.level is different false is returned.
 func isOnlyLogLevelChanged(specArgs, statusArgs []string) bool {
-	diff := strings2.DiffStrings(specArgs, statusArgs)
+	diff := arangoStrings.DiffStrings(specArgs, statusArgs)
 	if len(diff) == 0 {
 		return false
 	}
@@ -187,27 +187,27 @@ func isOnlyLogLevelChanged(specArgs, statusArgs []string) bool {
 	return true
 }
 
-func internalContainerLifecycleCompare(spec, status *core.Container) Mode {
+func internalContainerLifecycleCompare(spec, status *core.Container) compare.Mode {
 	if spec.Lifecycle == nil && status.Lifecycle == nil {
-		return SkippedRotation
+		return compare.SkippedRotation
 	}
 
 	if spec.Lifecycle == nil {
 		status.Lifecycle = nil
-		return SilentRotation
+		return compare.SilentRotation
 	}
 
 	if status.Lifecycle == nil {
 		status.Lifecycle = spec.Lifecycle
-		return SilentRotation
+		return compare.SilentRotation
 	}
 
 	if !equality.Semantic.DeepEqual(spec.Lifecycle, status.Lifecycle) {
 		status.Lifecycle = spec.Lifecycle.DeepCopy()
-		return SilentRotation
+		return compare.SilentRotation
 	}
 
-	return SkippedRotation
+	return compare.SkippedRotation
 }
 
 func areProbesEqual(a, b *core.Probe) bool {

pkg/deployment/rotation/arangod_containers_test.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -29,6 +29,7 @@ import (
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/apis/shared"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/actions"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
 func Test_ArangoDContainers_SidecarImages(t *testing.T) {
@@ -39,7 +40,7 @@ func Test_ArangoDContainers_SidecarImages(t *testing.T) {
 			status: buildPodSpec(addContainer(shared.ServerContainerName), addSidecarWithImage("sidecar", "local:2.0")),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: InPlaceRotation,
+				expectedMode: compare.InPlaceRotation,
 				expectedPlan: api.Plan{
 					actions.NewClusterAction(api.ActionTypeRuntimeContainerImageUpdate),
 				},
@@ -51,7 +52,7 @@ func Test_ArangoDContainers_SidecarImages(t *testing.T) {
 			status: buildPodSpec(addSidecarWithImage("sidecar1", "local:1.0"), addSidecarWithImage("sidecar", "local:2.0")),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: InPlaceRotation,
+				expectedMode: compare.InPlaceRotation,
 				expectedPlan: api.Plan{
 					actions.NewClusterAction(api.ActionTypeRuntimeContainerImageUpdate),
 				},
@@ -75,7 +76,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: SkippedRotation,
+					expectedMode: compare.SkippedRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -94,7 +95,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: SilentRotation,
+					expectedMode: compare.SilentRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -120,7 +121,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: GracefulRotation,
+					expectedMode: compare.GracefulRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -143,7 +144,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: SilentRotation,
+					expectedMode: compare.SilentRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -164,7 +165,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: SilentRotation,
+					expectedMode: compare.SilentRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -189,7 +190,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: SilentRotation,
+					expectedMode: compare.SilentRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -214,7 +215,7 @@ func Test_InitContainers(t *testing.T) {
 				})),
 
 				TestCaseOverride: TestCaseOverride{
-					expectedMode: GracefulRotation,
+					expectedMode: compare.GracefulRotation,
 				},
 
 				groupSpec: buildGroupSpec(func(depl *api.ServerGroupSpec) {
@@ -229,11 +230,11 @@ func Test_InitContainers(t *testing.T) {
 	})
 }
 
-func logLevelTestCaseGen(name string, mode Mode, spec, status []string) TestCase {
+func logLevelTestCaseGen(name string, mode compare.Mode, spec, status []string) TestCase {
 	var c TestCase
 	c.name = name
 	c.expectedMode = mode
-	if c.expectedMode == InPlaceRotation {
+	if c.expectedMode == compare.InPlaceRotation {
 		c.expectedPlan = api.Plan{
 			actions.NewClusterAction(api.ActionTypeRuntimeContainerArgsLogLevelUpdate),
 		}
@@ -247,27 +248,27 @@ func logLevelTestCaseGen(name string, mode Mode, spec, status []string) TestCase
 func Test_Container_LogArgs(t *testing.T) {
 	testCases := []TestCase{
 		logLevelTestCaseGen("Only log level arguments of the ArangoDB server have been changed",
-			InPlaceRotation,
+			compare.InPlaceRotation,
 			[]string{"--log.level=INFO", "--log.level=requests=error"},
 			[]string{"--log.level=INFO"}),
 		logLevelTestCaseGen("ArangoDB server arguments have not been changed",
-			SkippedRotation,
+			compare.SkippedRotation,
 			[]string{"--log.level=INFO"},
 			[]string{"--log.level=INFO"}),
 		logLevelTestCaseGen("Multi ArangoDB server arguments have not been changed",
-			SkippedRotation,
+			compare.SkippedRotation,
 			[]string{"--log.level=INFO", "--log.level=requests=debug"},
 			[]string{"--log.level=INFO", "--log.level=requests=debug"}),
 		logLevelTestCaseGen("Not only log argument changed",
-			GracefulRotation,
+			compare.GracefulRotation,
 			[]string{"--log.level=INFO", "--server.endpoint=localhost"},
 			[]string{"--log.level=INFO"}),
 		logLevelTestCaseGen("Change of order with existing arg & switch to DEBUG",
-			InPlaceRotation,
+			compare.InPlaceRotation,
 			[]string{"--log.level=DEBUG", "--foo"},
 			[]string{"--foo", "--log.level=INFO"}),
 		logLevelTestCaseGen("Removal of arg",
-			InPlaceRotation,
+			compare.InPlaceRotation,
 			[]string{"--foo", "--log.level=INFO"},
 			[]string{"--foo"}),
 	}
@@ -283,7 +284,7 @@ func Test_Container_Args(t *testing.T) {
 				[]string{"--log.level=INFO", "--log.level=requests=error"})),
 			status: buildPodSpec(addContainerWithCommand("sidecar", []string{"--log.level=INFO"})),
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 	}
@@ -314,7 +315,7 @@ func Test_Container_Ports(t *testing.T) {
 				}
 			})),
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare.SilentRotation,
 			},
 		},
 		{
@@ -338,7 +339,7 @@ func Test_Container_Ports(t *testing.T) {
 				}
 			})),
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 	}

pkg/deployment/rotation/arangod_envs.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -28,18 +28,19 @@ import (
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/topology"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/constants"
 )
 
-func compareServerContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) comparePodContainerFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+func compareServerContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
 		specV := mapEnvs(spec)
 		statusV := mapEnvs(status)
 
 		diff := getEnvDiffFromPods(specV, statusV)
 
 		if len(diff) == 0 {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		for k := range diff {
@@ -53,24 +54,24 @@ func compareServerContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec,
 				// Lifecycle envs can change without restart
 				continue
 			default:
-				return GracefulRotation, nil, nil
+				return compare.GracefulRotation, nil, nil
 			}
 		}
 
 		status.Env = spec.Env
-		return SilentRotation, nil, nil
+		return compare.SilentRotation, nil, nil
 	}
 }
 
-func compareAnyContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) comparePodContainerFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+func compareAnyContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
 		specV := mapEnvs(spec)
 		statusV := mapEnvs(status)
 
 		diff := getEnvDiffFromPods(specV, statusV)
 
 		if len(diff) == 0 {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		for k := range diff {
@@ -79,12 +80,12 @@ func compareAnyContainerEnvs(ds api.DeploymentSpec, g api.ServerGroup, spec, sta
 				// Lifecycle envs can change without restart
 				continue
 			default:
-				return GracefulRotation, nil, nil
+				return compare.GracefulRotation, nil, nil
 			}
 		}
 
 		status.Env = spec.Env
-		return SilentRotation, nil, nil
+		return compare.SilentRotation, nil, nil
 	}
 }
 

pkg/deployment/rotation/arangod_probes.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -25,13 +25,14 @@ import (
 	"k8s.io/apimachinery/pkg/api/equality"
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
-func compareServerContainerProbes(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) comparePodContainerFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+func compareServerContainerProbes(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
 		if !areProbesEqual(spec.StartupProbe, status.StartupProbe) {
 			status.StartupProbe = spec.StartupProbe
-			mode = mode.And(SilentRotation)
+			mode = mode.And(compare.SilentRotation)
 		}
 
 		if !areProbesEqual(spec.ReadinessProbe, status.ReadinessProbe) {
@@ -42,7 +43,7 @@ func compareServerContainerProbes(ds api.DeploymentSpec, g api.ServerGroup, spec
 
 				if equality.Semantic.DeepDerivative(spec.ReadinessProbe, q) {
 					status.ReadinessProbe = spec.ReadinessProbe
-					mode = mode.And(SilentRotation)
+					mode = mode.And(compare.SilentRotation)
 				}
 			}
 		}
@@ -55,7 +56,7 @@ func compareServerContainerProbes(ds api.DeploymentSpec, g api.ServerGroup, spec
 
 				if equality.Semantic.DeepDerivative(spec.LivenessProbe, q) {
 					status.LivenessProbe = spec.LivenessProbe
-					mode = mode.And(SilentRotation)
+					mode = mode.And(compare.SilentRotation)
 				}
 			}
 		}

pkg/deployment/rotation/arangod_test.go

@@ -27,6 +27,7 @@ import (
 
 	"github.com/arangodb/kube-arangodb/pkg/deployment/topology"
 	"github.com/arangodb/kube-arangodb/pkg/util"
+	compare2 "github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
 func Test_ArangoD_SchedulerName(t *testing.T) {
@@ -41,7 +42,7 @@ func Test_ArangoD_SchedulerName(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -54,7 +55,7 @@ func Test_ArangoD_SchedulerName(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -67,7 +68,7 @@ func Test_ArangoD_SchedulerName(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare2.SkippedRotation,
 			},
 		},
 	}
@@ -87,7 +88,7 @@ func Test_ArangoD_TerminationGracePeriodSeconds(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -100,7 +101,7 @@ func Test_ArangoD_TerminationGracePeriodSeconds(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -113,7 +114,7 @@ func Test_ArangoD_TerminationGracePeriodSeconds(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 	}
@@ -150,7 +151,7 @@ func Test_ArangoD_Affinity(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -180,7 +181,7 @@ func Test_ArangoD_Affinity(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -229,7 +230,7 @@ func Test_ArangoD_Affinity(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -278,7 +279,7 @@ func Test_ArangoD_Affinity(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -327,7 +328,7 @@ func Test_ArangoD_Affinity(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 	}
@@ -351,7 +352,7 @@ func Test_ArangoD_Labels(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare2.SkippedRotation,
 			},
 		},
 		{
@@ -368,7 +369,7 @@ func Test_ArangoD_Labels(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare2.SkippedRotation,
 			},
 		},
 		{
@@ -387,7 +388,7 @@ func Test_ArangoD_Labels(t *testing.T) {
 			}),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare2.SkippedRotation,
 			},
 		},
 	}
@@ -414,7 +415,7 @@ func Test_ArangoD_Envs_Zone(t *testing.T) {
 			})),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -434,7 +435,7 @@ func Test_ArangoD_Envs_Zone(t *testing.T) {
 			})),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -459,7 +460,7 @@ func Test_ArangoD_Envs_Zone(t *testing.T) {
 			})),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare2.SilentRotation,
 			},
 		},
 		{
@@ -488,7 +489,7 @@ func Test_ArangoD_Envs_Zone(t *testing.T) {
 			})),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare2.GracefulRotation,
 			},
 		},
 	}

pkg/deployment/rotation/arangod_tolerations.go

@@ -26,15 +26,16 @@ import (
 	core "k8s.io/api/core/v1"
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
-func comparePodTolerations(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
-		if !reflect.DeepEqual(spec.Tolerations, status.Tolerations) {
+func comparePodTolerations(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
+		if !reflect.DeepEqual(spec.Spec.Tolerations, status.Spec.Tolerations) {
 			plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerSyncTolerations))
 
-			status.Tolerations = spec.Tolerations
-			mode = mode.And(InPlaceRotation)
+			status.Spec.Tolerations = spec.Spec.Tolerations
+			mode = mode.And(compare.InPlaceRotation)
 
 			return
 		}

pkg/deployment/rotation/arangod_volume_mounts.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,17 +27,18 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/apis/shared"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
-func compareServerContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) comparePodContainerFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+func compareServerContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
 		specV := mapVolumeMounts(spec)
 		statusV := mapVolumeMounts(status)
 
 		diff := getVolumeMountsDiffFromPods(specV, statusV)
 
 		if len(diff) == 0 {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		for k, v := range diff {
@@ -46,34 +47,34 @@ func compareServerContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup
 				// We are fine, should be just replaced
 				if v.a == nil {
 					// we remove volume
-					return GracefulRotation, nil, nil
+					return compare.GracefulRotation, nil, nil
 				}
 
 				if ds.Mode.Get().ServingGroup() == g {
 					// Always enforce on serving group
-					return GracefulRotation, nil, nil
+					return compare.GracefulRotation, nil, nil
 				}
 			case shared.LifecycleVolumeName:
 				// Do nothing
 			default:
-				return GracefulRotation, nil, nil
+				return compare.GracefulRotation, nil, nil
 			}
 		}
 
 		status.VolumeMounts = spec.VolumeMounts
-		return SilentRotation, nil, nil
+		return compare.SilentRotation, nil, nil
 	}
 }
 
-func compareAnyContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) comparePodContainerFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+func compareAnyContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.Container) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
 		specV := mapVolumeMounts(spec)
 		statusV := mapVolumeMounts(status)
 
 		diff := getVolumeMountsDiffFromPods(specV, statusV)
 
 		if len(diff) == 0 {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		for k := range diff {
@@ -81,12 +82,12 @@ func compareAnyContainerVolumeMounts(ds api.DeploymentSpec, g api.ServerGroup, s
 			case shared.LifecycleVolumeName:
 				// Do nothing
 			default:
-				return GracefulRotation, nil, nil
+				return compare.GracefulRotation, nil, nil
 			}
 		}
 
 		status.VolumeMounts = spec.VolumeMounts
-		return SilentRotation, nil, nil
+		return compare.SilentRotation, nil, nil
 	}
 }
 

pkg/deployment/rotation/arangod_volumes.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,21 +27,22 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/apis/shared"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
 type volumeDiff struct {
 	a, b *core.Volume
 }
 
-func comparePodVolumes(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.PodSpec) comparePodFunc {
-	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
-		specV := mapVolumes(spec)
-		statusV := mapVolumes(status)
+func comparePodVolumes(ds api.DeploymentSpec, g api.ServerGroup, spec, status *core.PodTemplateSpec) compare.Func {
+	return func(builder api.ActionBuilder) (mode compare.Mode, plan api.Plan, err error) {
+		specV := mapVolumes(spec.Spec)
+		statusV := mapVolumes(status.Spec)
 
 		diff := getVolumesDiffFromPods(specV, statusV)
 
 		if len(diff) == 0 {
-			return SkippedRotation, nil, nil
+			return compare.SkippedRotation, nil, nil
 		}
 
 		for k, v := range diff {
@@ -50,20 +51,20 @@ func comparePodVolumes(ds api.DeploymentSpec, g api.ServerGroup, spec, status *c
 				// We are fine, should be just replaced
 				if v.a == nil {
 					// we remove volume
-					return GracefulRotation, nil, nil
+					return compare.GracefulRotation, nil, nil
 				}
 
 				if ds.Mode.Get().ServingGroup() == g {
 					// Always enforce on serving group
-					return GracefulRotation, nil, nil
+					return compare.GracefulRotation, nil, nil
 				}
 			default:
-				return GracefulRotation, nil, nil
+				return compare.GracefulRotation, nil, nil
 			}
 		}
 
-		status.Volumes = spec.Volumes
-		return SilentRotation, nil, nil
+		status.Spec.Volumes = spec.Spec.Volumes
+		return compare.SilentRotation, nil, nil
 	}
 }
 
@@ -97,7 +98,7 @@ func getVolumesDiffFromPods(a, b map[string]*core.Volume) map[string]volumeDiff
 	return d
 }
 
-func mapVolumes(a *core.PodSpec) map[string]*core.Volume {
+func mapVolumes(a core.PodSpec) map[string]*core.Volume {
 	n := make(map[string]*core.Volume, len(a.Volumes))
 
 	for id := range a.Volumes {

pkg/deployment/rotation/arangod_volumes_test.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,6 +27,7 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/apis/shared"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
 func Test_ArangoD_Volumes(t *testing.T) {
@@ -39,7 +40,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			deploymentSpec: buildDeployment(),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare.SkippedRotation,
 			},
 		},
 		{
@@ -48,7 +49,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			status: buildPodSpec(addVolume("data", addVolumeConfigMapSource(&core.ConfigMapVolumeSource{}))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare.SkippedRotation,
 			},
 		},
 		{
@@ -61,7 +62,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			}))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -70,7 +71,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			status: buildPodSpec(),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -83,7 +84,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			}))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -98,23 +99,23 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			overrides: map[api.DeploymentMode]map[api.ServerGroup]TestCaseOverride{
 				api.DeploymentModeSingle: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeActiveFailover: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeCluster: {
 					api.ServerGroupCoordinators: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 			},
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare.SilentRotation,
 			},
 		},
 		{
@@ -125,23 +126,23 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			overrides: map[api.DeploymentMode]map[api.ServerGroup]TestCaseOverride{
 				api.DeploymentModeSingle: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeActiveFailover: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeCluster: {
 					api.ServerGroupCoordinators: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 			},
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare.SilentRotation,
 			},
 		},
 		{
@@ -154,7 +155,7 @@ func Test_ArangoD_Volumes(t *testing.T) {
 			}))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 	}
@@ -170,7 +171,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server")),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare.SkippedRotation,
 			},
 		},
 		{
@@ -183,7 +184,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			}))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SkippedRotation,
+				expectedMode: compare.SkippedRotation,
 			},
 		},
 		{
@@ -192,7 +193,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server", addVolumeMount("mount2"))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -201,7 +202,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server")),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -210,7 +211,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server", addVolumeMount("mount"))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -219,7 +220,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server", addVolumeMount("mount"))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -228,7 +229,7 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			status: buildPodSpec(addContainer("server", addVolumeMount(shared.ArangoDTimezoneVolumeName))),
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: GracefulRotation,
+				expectedMode: compare.GracefulRotation,
 			},
 		},
 		{
@@ -239,23 +240,23 @@ func Test_ArangoD_VolumeMounts(t *testing.T) {
 			overrides: map[api.DeploymentMode]map[api.ServerGroup]TestCaseOverride{
 				api.DeploymentModeSingle: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeActiveFailover: {
 					api.ServerGroupSingle: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 				api.DeploymentModeCluster: {
 					api.ServerGroupCoordinators: {
-						expectedMode: GracefulRotation,
+						expectedMode: compare.GracefulRotation,
 					},
 				},
 			},
 
 			TestCaseOverride: TestCaseOverride{
-				expectedMode: SilentRotation,
+				expectedMode: compare.SilentRotation,
 			},
 		},
 	}

pkg/deployment/rotation/check.go

@@ -29,49 +29,27 @@ import (
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/acs/sutil"
 	"github.com/arangodb/kube-arangodb/pkg/handlers/utils"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/constants"
 )
 
-type Mode int
-
-const (
-	SkippedRotation Mode = iota
-	// SilentRotation Propagates changes without restart. Returned plan is executed in High actions
-	SilentRotation
-	// InPlaceRotation Silently accept changes. Returned plan is executed in Normal actions
-	InPlaceRotation
-	// GracefulRotation Schedule pod restart. Returned plan is ignored
-	GracefulRotation
-	// EnforcedRotation Enforce pod restart. Returned plan is ignored
-	EnforcedRotation
-)
-
-// And returns the higher value of the rotation mode.
-func (m Mode) And(b Mode) Mode {
-	if m > b {
-		return m
-	}
-
-	return b
-}
-
 // CheckPossible returns true if rotation is possible
 func CheckPossible(member api.MemberStatus) bool {
 	return !member.Conditions.IsTrue(api.ConditionTypeTerminated)
 }
 
-func IsRotationRequired(acs sutil.ACS, spec api.DeploymentSpec, member api.MemberStatus, group api.ServerGroup, pod *core.Pod, specTemplate, statusTemplate *api.ArangoMemberPodTemplate) (mode Mode, plan api.Plan, specChecksum string, reason string, err error) {
+func IsRotationRequired(acs sutil.ACS, spec api.DeploymentSpec, member api.MemberStatus, group api.ServerGroup, pod *core.Pod, specTemplate, statusTemplate *api.ArangoMemberPodTemplate) (mode compare.Mode, plan api.Plan, specChecksum string, reason string, err error) {
 	// Determine if rotation is required based on plan and actions
 
 	// Set default mode for return value
-	mode = SkippedRotation
+	mode = compare.SkippedRotation
 
 	// We are under termination
 	if pod != nil {
 		if member.Conditions.IsTrue(api.ConditionTypeTerminating) || pod.DeletionTimestamp != nil {
 			if l := utils.StringList(pod.Finalizers); l.Has(constants.FinalizerPodGracefulShutdown) && !l.Has(constants.FinalizerDelayPodTermination) {
 				reason = "Recreation enforced by deleted state"
-				mode = EnforcedRotation
+				mode = compare.EnforcedRotation
 			}
 
 			return
@@ -85,7 +63,7 @@ func IsRotationRequired(acs sutil.ACS, spec api.DeploymentSpec, member api.Membe
 
 	if spec.MemberPropagationMode.Get() == api.DeploymentMemberPropagationModeAlways && member.Conditions.IsTrue(api.ConditionTypePendingRestart) {
 		reason = "Restart is pending"
-		mode = EnforcedRotation
+		mode = compare.EnforcedRotation
 		return
 	}
 
@@ -93,20 +71,20 @@ func IsRotationRequired(acs sutil.ACS, spec api.DeploymentSpec, member api.Membe
 	if pod != nil {
 		if member.Pod.GetUID() != pod.UID {
 			reason = "Pod UID does not match, this pod is not managed by Operator. Recreating"
-			mode = EnforcedRotation
+			mode = compare.EnforcedRotation
 			return
 		}
 
 		if _, ok := pod.Annotations[deployment.ArangoDeploymentPodRotateAnnotation]; ok {
 			reason = "Recreation enforced by annotation"
-			mode = EnforcedRotation
+			mode = compare.EnforcedRotation
 			return
 		}
 	}
 
 	if p := member.Pod; p != nil && p.SpecVersion == "" {
 		reason = "Pod Spec Version is nil - recreating pod"
-		mode = EnforcedRotation
+		mode = compare.EnforcedRotation
 		return
 	}
 
@@ -118,19 +96,19 @@ func IsRotationRequired(acs sutil.ACS, spec api.DeploymentSpec, member api.Membe
 	// Check if any of resize events are in place
 	if member.Conditions.IsTrue(api.ConditionTypePendingTLSRotation) {
 		reason = "TLS Rotation pending"
-		mode = EnforcedRotation
+		mode = compare.EnforcedRotation
 		return
 	}
 
 	if member.Conditions.Check(api.ConditionTypePVCResizePending).Exists().LastTransition(3 * time.Minute).Evaluate() {
 		reason = "PVC Resize pending for more than 3 min"
-		mode = EnforcedRotation
+		mode = compare.EnforcedRotation
 		return
 	}
 
-	if mode, plan, err := compare(spec, member, group, specTemplate, statusTemplate); err != nil {
-		return SkippedRotation, nil, specTemplate.Checksum, "", err
-	} else if mode == SkippedRotation {
+	if mode, plan, err := compareFunc(spec, member, group, specTemplate, statusTemplate); err != nil {
+		return compare.SkippedRotation, nil, specTemplate.Checksum, "", err
+	} else if mode == compare.SkippedRotation {
 		return mode, plan, specTemplate.Checksum, "No rotation needed", nil
 	} else {
 		return mode, plan, specTemplate.Checksum, "Pod needs rotation", nil

pkg/deployment/rotation/compare.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -21,124 +21,32 @@
 package rotation
 
 import (
+	"crypto/sha256"
 	"encoding/json"
+	"fmt"
 
-	jd "github.com/josephburnett/jd/lib"
-	"github.com/rs/zerolog/log"
 	core "k8s.io/api/core/v1"
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/actions"
-	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
-type comparePodFuncGen func(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.PodSpec) comparePodFunc
-type comparePodFunc func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error)
-
-func podFuncGenerator(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.PodSpec) func(c comparePodFuncGen) comparePodFunc {
-	return func(c comparePodFuncGen) comparePodFunc {
-		return c(deploymentSpec, group, spec, status)
-	}
-}
-
-type comparePodContainerFuncGen func(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.Container) comparePodContainerFunc
-type comparePodContainerFunc func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error)
-
-func podContainerFuncGenerator(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.Container) func(c comparePodContainerFuncGen) comparePodContainerFunc {
-	return func(c comparePodContainerFuncGen) comparePodContainerFunc {
-		return c(deploymentSpec, group, spec, status)
-	}
-}
-
-func comparePodContainer(builder api.ActionBuilder, f ...comparePodContainerFunc) (mode Mode, plan api.Plan, err error) {
-	for _, q := range f {
-		if m, p, err := q(builder); err != nil {
-			return 0, nil, err
-		} else {
-			mode = mode.And(m)
-			plan = append(plan, p...)
-		}
-	}
-
-	return
-}
-
-func comparePod(builder api.ActionBuilder, f ...comparePodFunc) (mode Mode, plan api.Plan, err error) {
-	for _, q := range f {
-		if m, p, err := q(builder); err != nil {
-			return 0, nil, err
-		} else {
-			mode = mode.And(m)
-			plan = append(plan, p...)
-		}
-	}
-
-	return
-}
-
-func compare(deploymentSpec api.DeploymentSpec, member api.MemberStatus, group api.ServerGroup,
-	spec, status *api.ArangoMemberPodTemplate) (mode Mode, plan api.Plan, err error) {
-
-	if spec.Checksum == status.Checksum {
-		return SkippedRotation, nil, nil
-	}
-
-	// If checksums are different and rotation is not needed and there are no changes between containers
-	// then silent rotation must be applied to adjust status checksum.
-	mode = SilentRotation
-
-	podStatus := status.PodSpec.DeepCopy()
-
-	// Try to fill fields
-	b := actions.NewActionBuilderWrap(group, member)
-
-	g := podFuncGenerator(deploymentSpec, group, &spec.PodSpec.Spec, &podStatus.Spec)
-
-	if m, p, err := comparePod(b, g(podCompare), g(affinityCompare), g(comparePodVolumes), g(containersCompare), g(initContainersCompare), g(comparePodTolerations)); err != nil {
-		log.Err(err).Msg("Error while getting pod diff")
-		return SkippedRotation, nil, err
-	} else {
-		mode = mode.And(m)
-		plan = append(plan, p...)
-	}
-
-	checksum, err := resources.ChecksumArangoPod(deploymentSpec.GetServerGroupSpec(group), resources.CreatePodFromTemplate(podStatus))
-	if err != nil {
-		log.Err(err).Msg("Error while getting pod checksum")
-		return SkippedRotation, nil, err
-	}
-
-	newStatus, err := api.GetArangoMemberPodTemplate(podStatus, checksum)
-	if err != nil {
-		log.Err(err).Msg("Error while getting template")
-		return SkippedRotation, nil, err
-	}
-
-	if spec.RotationNeeded(newStatus) {
-		line := logger.Str("id", member.ID)
-
-		specBytes, errA := json.Marshal(spec.PodSpec)
-		if errA == nil {
-			line = line.Str("spec", string(specBytes))
-		}
-
-		statusBytes, errB := json.Marshal(newStatus.PodSpec)
-		if errB == nil {
-			line = line.Str("status", string(statusBytes))
-		}
-
-		if errA == nil && errB == nil {
-			if specData, err := jd.ReadJsonString(string(specBytes)); err == nil && specData != nil {
-				if statusData, err := jd.ReadJsonString(string(statusBytes)); err == nil && statusData != nil {
-					line = line.Str("diff", specData.Diff(statusData).Render())
-				}
+func compareFunc(deploymentSpec api.DeploymentSpec, member api.MemberStatus, group api.ServerGroup,
+	spec, status *api.ArangoMemberPodTemplate) (mode compare.Mode, plan api.Plan, err error) {
+	return compare.P2[core.PodTemplateSpec, api.DeploymentSpec, api.ServerGroup](logger,
+		deploymentSpec, group,
+		actions.NewActionBuilderWrap(group, member),
+		func(in *core.PodTemplateSpec) (string, error) {
+			data, err := json.Marshal(in.Spec)
+			if err != nil {
+				return "", err
 			}
-		}
 
-		line.Info("Pod needs rotation - templates does not match")
+			checksum := fmt.Sprintf("%0x", sha256.Sum256(data))
 
-		return GracefulRotation, nil, nil
-	}
-
-	return
+			return checksum, nil
+		},
+		spec, status,
+		podCompare, affinityCompare, comparePodVolumes, containersCompare, initContainersCompare, comparePodTolerations)
 }

pkg/deployment/rotation/predefined_test.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -30,6 +30,7 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
+	"github.com/arangodb/kube-arangodb/pkg/util/compare"
 	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
 )
 
@@ -43,7 +44,7 @@ var podLifecycleChange000Spec []byte
 //go:embed testdata/pod_lifecycle_change.000.status.json
 var podLifecycleChange000Status []byte
 
-func runPredefinedTests(t *testing.T, spec, status []byte) (mode Mode, plan api.Plan, err error) {
+func runPredefinedTests(t *testing.T, spec, status []byte) (mode compare.Mode, plan api.Plan, err error) {
 	var specO, statusO core.PodTemplateSpec
 
 	require.NoError(t, json.Unmarshal(spec, &specO))
@@ -63,7 +64,7 @@ func runPredefinedTests(t *testing.T, spec, status []byte) (mode Mode, plan api.
 	statusT, err := api.GetArangoMemberPodTemplate(&statusO, statusC)
 	require.NoError(t, err)
 
-	return compare(obj, member, api.ServerGroupUnknown, specT, statusT)
+	return compareFunc(obj, member, api.ServerGroupUnknown, specT, statusT)
 }
 
 func Test_PredefinedTests(t *testing.T) {
@@ -71,6 +72,6 @@ func Test_PredefinedTests(t *testing.T) {
 		mode, plan, err := runPredefinedTests(t, podLifecycleChange000Spec, podLifecycleChange000Status)
 		require.NoError(t, err)
 		require.Empty(t, plan)
-		require.Equal(t, SilentRotation, mode)
+		require.Equal(t, compare.SilentRotation, mode)
 	})
 }

pkg/deployment/rotation/utils_test.go

@@ -1,7 +1,7 @@
 //
 // DISCLAIMER
 //
-// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+// Copyright 2016-2023 ArangoDB GmbH, Cologne, Germany
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -28,10 +28,11 @@ import (
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
+	compare2 "github.com/arangodb/kube-arangodb/pkg/util/compare"
 )
 
 type TestCaseOverride struct {
-	expectedMode Mode
+	expectedMode compare2.Mode
 	expectedPlan api.Plan
 	expectedErr  string
 }
@@ -98,7 +99,7 @@ func runTestCasesForModeAndGroup(t *testing.T, m api.DeploymentMode, g api.Serve
 		pspec := newTemplateFromSpec(t, tc.spec, g, *ds)
 		pstatus := newTemplateFromSpec(t, tc.status, g, *ds)
 
-		mode, plan, err := compare(*ds, api.MemberStatus{ID: "id"}, g, pspec, pstatus)
+		mode, plan, err := compareFunc(*ds, api.MemberStatus{ID: "id"}, g, pspec, pstatus)
 
 		q := tc.TestCaseOverride
 
@@ -113,7 +114,7 @@ func runTestCasesForModeAndGroup(t *testing.T, m api.DeploymentMode, g api.Serve
 			require.Equal(t, q.expectedMode, mode)
 
 			switch mode {
-			case InPlaceRotation:
+			case compare2.InPlaceRotation:
 				require.Len(t, plan, len(q.expectedPlan))
 
 				for i := range plan {

pkg/util/compare/compare.go

@@ -0,0 +1,98 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+import (
+	"reflect"
+
+	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+	"github.com/arangodb/kube-arangodb/pkg/logging"
+)
+
+// P2 runs compare of the provided templates with 2 generic parameters
+func P2[T interface{}, P1, P2 interface{}](
+	log logging.Logger,
+	p1 P1, p2 P2,
+	actionBuilder api.ActionBuilder,
+	checksum Checksum[T],
+	spec, status Template[T],
+	evaluators ...GenP2[T, P1, P2]) (mode Mode, plan api.Plan, err error) {
+	if spec.GetChecksum() == status.GetChecksum() {
+		return SkippedRotation, nil, nil
+	}
+
+	mode = SilentRotation
+
+	// Try to fill fields
+	newStatus := status.GetTemplate()
+	currentSpec := spec.GetTemplate()
+
+	g := NewFuncGenP2[T](p1, p2, currentSpec, newStatus)
+
+	evaluatorsFunc := make([]Func, len(evaluators))
+
+	for id := range evaluators {
+		evaluatorsFunc[id] = g(evaluators[id])
+	}
+
+	if m, p, err := Evaluate(actionBuilder, evaluatorsFunc...); err != nil {
+		log.Err(err).Error("Error while getting diff")
+		return SkippedRotation, nil, err
+	} else {
+		mode = mode.And(m)
+		plan = append(plan, p...)
+	}
+
+	// Diff has been generated! Proceed with calculations
+
+	checksumString, err := checksum(newStatus)
+	if err != nil {
+		log.Err(err).Error("Error while getting checksum")
+		return SkippedRotation, nil, err
+	}
+
+	if checksumString != spec.GetChecksum() {
+		line := log
+
+		// Rotate anyway!
+		specData, statusData, diff, err := Diff(currentSpec, newStatus)
+		if err == nil {
+
+			if diff != "" {
+				line = line.Str("diff", diff)
+			}
+
+			if specData != "" {
+				line = line.Str("spec", specData)
+			}
+
+			if statusData != "" {
+				line = line.Str("status", statusData)
+			}
+		}
+
+		line.Info("Resource %s needs rotation - templates does not match", reflect.TypeOf(currentSpec).String())
+
+		return GracefulRotation, nil, nil
+	}
+
+	return
+}

pkg/util/compare/diff.go

@@ -0,0 +1,53 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+import (
+	"encoding/json"
+
+	jd "github.com/josephburnett/jd/lib"
+)
+
+func Diff[T interface{}](spec, status *T) (specData, statusData, diff string, outErr error) {
+	specBytes, err := json.Marshal(spec)
+	if err != nil {
+		return "", "", "", err
+	}
+	specData = string(specBytes)
+
+	statusBytes, err := json.Marshal(status)
+	if err != nil {
+		return "", "", "", err
+	}
+	statusData = string(statusBytes)
+
+	if specData, err := jd.ReadJsonString(string(specBytes)); err != nil {
+		return "", "", "", err
+	} else if specData != nil {
+		if statusData, err := jd.ReadJsonString(string(statusBytes)); err != nil {
+			return "", "", "", err
+		} else if statusData != nil {
+			diff = specData.Diff(statusData).Render()
+		}
+	}
+
+	return
+}

pkg/util/compare/gen.go

@@ -0,0 +1,31 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+type GenP2[T, P1, P2 interface{}] func(p1 P1, p2 P2, spec, status *T) Func
+
+type FuncGenP2[T, P1, P2 interface{}] func(in GenP2[T, P1, P2]) Func
+
+func NewFuncGenP2[T, P1, P2 interface{}](p1 P1, p2 P2, spec, status *T) FuncGenP2[T, P1, P2] {
+	return func(in GenP2[T, P1, P2]) Func {
+		return in(p1, p2, spec, status)
+	}
+}

pkg/util/compare/interfaces.go

@@ -0,0 +1,70 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+import (
+	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+)
+
+type Template[T interface{}] interface {
+	GetTemplate() *T
+	SetTemplate(*T)
+
+	GetTemplateChecksum() string
+	SetTemplateChecksum(string)
+
+	GetChecksum() string
+	SetChecksum(string)
+}
+
+type Checksum[T interface{}] func(in *T) (string, error)
+
+type FuncGen[T interface{}] func(spec, status *T) Func
+
+type Func func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error)
+
+func Merge(f ...Func) Func {
+	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+		for _, q := range f {
+			if m, p, err := q(builder); err != nil {
+				return 0, nil, err
+			} else {
+				mode = mode.And(m)
+				plan = append(plan, p...)
+			}
+		}
+
+		return
+	}
+}
+
+func Evaluate(builder api.ActionBuilder, f ...Func) (mode Mode, plan api.Plan, err error) {
+	for _, q := range f {
+		if m, p, err := q(builder); err != nil {
+			return 0, nil, err
+		} else {
+			mode = mode.And(m)
+			plan = append(plan, p...)
+		}
+	}
+
+	return
+}

pkg/util/compare/mode.go

@@ -0,0 +1,54 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+import (
+	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+)
+
+type Mode int
+
+const (
+	SkippedRotation Mode = iota
+	// SilentRotation Propagates changes without restart. Returned plan is executed in High actions
+	SilentRotation
+	// InPlaceRotation Silently accept changes. Returned plan is executed in Normal actions
+	InPlaceRotation
+	// GracefulRotation Schedule pod restart. Returned plan is ignored
+	GracefulRotation
+	// EnforcedRotation Enforce pod restart. Returned plan is ignored
+	EnforcedRotation
+)
+
+// And returns the higher value of the rotation mode.
+func (m Mode) And(b Mode) Mode {
+	if m > b {
+		return m
+	}
+
+	return b
+}
+
+func (m Mode) Func() Func {
+	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
+		return m, nil, nil
+	}
+}

pkg/util/compare/sub.go

@@ -0,0 +1,63 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package compare
+
+type SubElementExtractor[T1, T2 interface{}] func(in *T1) *T2
+
+func SubElementsP2[T1, T2, P1, P2 interface{}](extractor SubElementExtractor[T1, T2], gens ...GenP2[T2, P1, P2]) GenP2[T1, P1, P2] {
+	return func(p1 P1, p2 P2, spec, status *T1) Func {
+		specF := extractor(spec)
+		statusF := extractor(status)
+
+		funcs := make([]Func, len(gens))
+
+		for id := range gens {
+			funcs[id] = gens[id](p1, p2, specF, statusF)
+		}
+
+		return Merge(funcs...)
+	}
+}
+
+func ArrayExtractorP2[T, P1, P2 interface{}](gens ...GenP2[T, P1, P2]) GenP2[[]T, P1, P2] {
+	return func(p1 P1, p2 P2, spec, status *[]T) Func {
+		if spec == nil || status == nil {
+			return SkippedRotation.Func()
+		}
+
+		specA := *spec
+		statusA := *status
+
+		if len(specA) != len(statusA) {
+			return SkippedRotation.Func()
+		}
+
+		funcs := make([]Func, 0, len(specA)*len(gens))
+		// Iterate over ids
+		for id := range specA {
+			for _, gen := range gens {
+				funcs = append(funcs, gen(p1, p2, &specA[id], &statusA[id]))
+			}
+		}
+
+		return Merge(funcs...)
+	}
+}

pkg/util/k8sutil/deepcopy.go

@@ -0,0 +1,25 @@
+//
+// DISCLAIMER
+//
+// Copyright 2023 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package k8sutil
+
+type DeepCopy[T interface{}] interface {
+	DeepCopy() T
+}