[Feature] Add member replacement condition (#898)

Author: ajanikow

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## [master](https://github.com/arangodb/kube-arangodb/tree/master) (N/A)
 - Do not check License V2 on Community images
 - Add status.members.<group>.
+- Define MemberReplacementRequired condition
 
 ## [1.2.7](https://github.com/arangodb/kube-arangodb/tree/1.2.7) (2022-01-17)
 - Add Plan BackOff functionality

pkg/apis/deployment/v1/conditions.go

@@ -73,6 +73,8 @@ const (
 	ConditionTypePendingRestart ConditionType = "PendingRestart"
 	// ConditionTypeRestart indicates that restart will be started
 	ConditionTypeRestart ConditionType = "Restart"
+	// MemberReplacementRequired indicates that the member requires a replacement to proceed with next actions.
+	MemberReplacementRequired ConditionType = "MemberReplacementRequired"
 
 	// ConditionTypePendingTLSRotation indicates that TLS rotation is pending
 	ConditionTypePendingTLSRotation ConditionType = "PendingTLSRotation"

pkg/apis/deployment/v2alpha1/conditions.go

@@ -73,6 +73,8 @@ const (
 	ConditionTypePendingRestart ConditionType = "PendingRestart"
 	// ConditionTypeRestart indicates that restart will be started
 	ConditionTypeRestart ConditionType = "Restart"
+	// MemberReplacementRequired indicates that the member requires a replacement to proceed with next actions.
+	MemberReplacementRequired ConditionType = "MemberReplacementRequired"
 
 	// ConditionTypePendingTLSRotation indicates that TLS rotation is pending
 	ConditionTypePendingTLSRotation ConditionType = "PendingTLSRotation"

pkg/deployment/reconcile/condition_member_recreation.go

@@ -0,0 +1,78 @@
+//
+// DISCLAIMER
+//
+// Copyright 2016-2022 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 reconcile
+
+import (
+	"context"
+	"strings"
+
+	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
+	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
+	inspectorInterface "github.com/arangodb/kube-arangodb/pkg/util/k8sutil/inspector"
+	"github.com/rs/zerolog"
+)
+
+func createMemberRecreationConditionsPlan(ctx context.Context,
+	log zerolog.Logger, apiObject k8sutil.APIObject,
+	spec api.DeploymentSpec, status api.DeploymentStatus,
+	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext) api.Plan {
+	var p api.Plan
+
+	for _, m := range status.Members.AsList() {
+		resp, recreate := EvaluateMemberRecreationCondition(ctx, log, apiObject, spec, status, m.Group, m.Member, cachedStatus, context)
+
+		if !recreate {
+			if _, ok := m.Member.Conditions.Get(api.MemberReplacementRequired); ok {
+				// Unset condition
+				p = append(p, removeMemberConditionActionV2("Member replacement not required", api.MemberReplacementRequired, m.Group, m.Member.ID))
+			}
+		} else {
+			if c, ok := m.Member.Conditions.Get(api.MemberReplacementRequired); !ok || !c.IsTrue() || c.Message != resp {
+				// Update condition
+				p = append(p, updateMemberConditionActionV2("Member replacement required", api.MemberReplacementRequired, m.Group, m.Member.ID, true, "Member replacement required", resp, ""))
+			}
+		}
+	}
+
+	return p
+}
+
+type MemberRecreationConditionEvaluator func(ctx context.Context,
+	log zerolog.Logger, apiObject k8sutil.APIObject,
+	spec api.DeploymentSpec, status api.DeploymentStatus,
+	group api.ServerGroup, member api.MemberStatus,
+	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext) (string, bool)
+
+func EvaluateMemberRecreationCondition(ctx context.Context,
+	log zerolog.Logger, apiObject k8sutil.APIObject,
+	spec api.DeploymentSpec, status api.DeploymentStatus,
+	group api.ServerGroup, member api.MemberStatus,
+	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext, evaluators ...MemberRecreationConditionEvaluator) (string, bool) {
+	args := make([]string, 0, len(evaluators))
+
+	for _, e := range evaluators {
+		if s, ok := e(ctx, log, apiObject, spec, status, group, member, cachedStatus, context); ok {
+			args = append(args, s)
+		}
+	}
+
+	return strings.Join(args, ", "), len(args) > 0
+}

pkg/deployment/reconcile/plan_builder_high.go

@@ -51,6 +51,7 @@ func createHighPlan(ctx context.Context, log zerolog.Logger, apiObject k8sutil.A
 		ApplyIfEmpty(createCleanOutPlan).
 		ApplyIfEmpty(updateMemberUpdateConditionsPlan).
 		ApplyIfEmpty(updateMemberRotationConditionsPlan).
+		ApplyIfEmpty(createMemberRecreationConditionsPlan).
 		ApplyIfEmpty(createTopologyMemberUpdatePlan).
 		ApplyIfEmptyWithBackOff(LicenseCheck, 30*time.Second, updateClusterLicense).
 		ApplyIfEmpty(createTopologyMemberConditionPlan).

pkg/deployment/reconcile/plan_builder_utils.go

@@ -78,3 +78,24 @@ func updateConditionActionV2(actionReason string, conditionType api.ConditionTyp
 		AddParam(setConditionActionV2KeyMessage, message).
 		AddParam(setConditionActionV2KeyHash, hash)
 }
+
+func removeMemberConditionActionV2(actionReason string, conditionType api.ConditionType, group api.ServerGroup, member string) api.Action {
+	return api.NewAction(api.ActionTypeSetMemberConditionV2, group, member, actionReason).
+		AddParam(setConditionActionV2KeyAction, string(conditionType)).
+		AddParam(setConditionActionV2KeyType, setConditionActionV2KeyTypeRemove)
+}
+
+func updateMemberConditionActionV2(actionReason string, conditionType api.ConditionType, group api.ServerGroup, member string, status bool, reason, message, hash string) api.Action {
+	statusBool := core.ConditionTrue
+	if !status {
+		statusBool = core.ConditionFalse
+	}
+
+	return api.NewAction(api.ActionTypeSetMemberConditionV2, group, member, actionReason).
+		AddParam(setConditionActionV2KeyAction, string(conditionType)).
+		AddParam(setConditionActionV2KeyType, setConditionActionV2KeyTypeAdd).
+		AddParam(setConditionActionV2KeyStatus, string(statusBool)).
+		AddParam(setConditionActionV2KeyReason, reason).
+		AddParam(setConditionActionV2KeyMessage, message).
+		AddParam(setConditionActionV2KeyHash, hash)
+}