[Feature] Topology env propagation (#806)

Author: ajanikow

CHANGELOG.md

@@ -6,6 +6,7 @@
 - Switch ArangoDB Image Discovery process from Headless Service to Pod IP
 - Fix PVC Resize for Single servers
 - Add Topology support
+- Add ARANGODB_ZONE env to Topology Managed pods
 
 ## [1.2.3](https://github.com/arangodb/kube-arangodb/tree/1.2.3) (2021-09-24)
 - Update UBI Image to 8.4

pkg/deployment/pod/topology.community.go

@@ -0,0 +1,45 @@
+//
+// DISCLAIMER
+//
+// Copyright 2020 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
+//
+
+// +build !enterprise
+
+package pod
+
+import (
+	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
+	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil/interfaces"
+	core "k8s.io/api/core/v1"
+)
+
+func (t topology) Args(i Input) k8sutil.OptionPairs {
+	return nil
+}
+
+func (t topology) Volumes(i Input) ([]core.Volume, []core.VolumeMount) {
+	return nil, nil
+}
+
+func (t topology) Envs(i Input) []core.EnvVar {
+	return nil
+}
+
+func (t topology) Verify(i Input, cachedStatus interfaces.Inspector) error {
+	return nil
+}

pkg/deployment/pod/topology.go

@@ -0,0 +1,27 @@
+//
+// DISCLAIMER
+//
+// Copyright 2020 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 pod
+
+func Topology() Builder {
+	return topology{}
+}
+
+type topology struct{}

pkg/deployment/reconcile/plan_builder_scale.go

@@ -35,9 +35,7 @@ func createScaleUPMemberPlan(ctx context.Context,
 	log zerolog.Logger, apiObject k8sutil.APIObject,
 	spec api.DeploymentSpec, status api.DeploymentStatus,
 	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext) api.Plan {
-	return createScaleMemberPlan(ctx, log, apiObject, spec, status, cachedStatus, context).Filter(func(a api.Action) bool {
-		return a.Type == api.ActionTypeAddMember
-	})
+	return createScaleMemberPlan(ctx, log, apiObject, spec, status, cachedStatus, context).Filter(filterScaleUP)
 }
 
 func createScaleMemberPlan(ctx context.Context,
@@ -50,16 +48,17 @@ func createScaleMemberPlan(ctx context.Context,
 	switch spec.GetMode() {
 	case api.DeploymentModeSingle:
 		// Never scale down
+		plan = append(plan, createScalePlan(log, status, status.Members.Single, api.ServerGroupSingle, 1).Filter(filterScaleUP)...)
 	case api.DeploymentModeActiveFailover:
 		// Only scale agents & singles
 		if a := status.Agency; a != nil && a.Size != nil {
-			plan = append(plan, createScalePlan(log, status, status.Members.Agents, api.ServerGroupAgents, int(*a.Size))...)
+			plan = append(plan, createScalePlan(log, status, status.Members.Agents, api.ServerGroupAgents, int(*a.Size)).Filter(filterScaleUP)...)
 		}
 		plan = append(plan, createScalePlan(log, status, status.Members.Single, api.ServerGroupSingle, spec.Single.GetCount())...)
 	case api.DeploymentModeCluster:
 		// Scale agents, dbservers, coordinators
 		if a := status.Agency; a != nil && a.Size != nil {
-			plan = append(plan, createScalePlan(log, status, status.Members.Agents, api.ServerGroupAgents, int(*a.Size))...)
+			plan = append(plan, createScalePlan(log, status, status.Members.Agents, api.ServerGroupAgents, int(*a.Size)).Filter(filterScaleUP)...)
 		}
 		plan = append(plan, createScalePlan(log, status, status.Members.DBServers, api.ServerGroupDBServers, spec.DBServers.GetCount())...)
 		plan = append(plan, createScalePlan(log, status, status.Members.Coordinators, api.ServerGroupCoordinators, spec.Coordinators.GetCount())...)
@@ -157,3 +156,7 @@ func createReplaceMemberPlan(ctx context.Context,
 
 	return plan
 }
+
+func filterScaleUP(a api.Action) bool {
+	return a.Type == api.ActionTypeAddMember
+}

pkg/deployment/reconcile/plan_builder_test.go

@@ -362,7 +362,7 @@ func TestCreatePlanSingleScale(t *testing.T) {
 
 	newPlan, changed := createNormalPlan(ctx, log, depl, nil, spec, status, inspector.NewEmptyInspector(), c)
 	assert.True(t, changed)
-	assert.Len(t, newPlan, 0) // Single mode does not scale
+	assert.Len(t, newPlan, 1)
 
 	// Test with 1 single member
 	status.Members.Single = api.MemberStatusList{
@@ -375,6 +375,12 @@ func TestCreatePlanSingleScale(t *testing.T) {
 	assert.True(t, changed)
 	assert.Len(t, newPlan, 0) // Single mode does not scale
 
+	spec.Single.Count = util.NewInt(2)
+	newPlan, changed = createNormalPlan(ctx, log, depl, nil, spec, status, inspector.NewEmptyInspector(), c)
+	assert.True(t, changed)
+	assert.Len(t, newPlan, 0) // Single mode does not scale
+
+	spec.Single.Count = util.NewInt(1)
 	// Test with 2 single members (which should not happen) and try to scale down
 	status.Members.Single = api.MemberStatusList{
 		api.MemberStatus{
@@ -388,7 +394,7 @@ func TestCreatePlanSingleScale(t *testing.T) {
 	}
 	newPlan, changed = createNormalPlan(ctx, log, depl, nil, spec, status, inspector.NewEmptyInspector(), c)
 	assert.True(t, changed)
-	assert.Len(t, newPlan, 0) // Single mode does not scale
+	assert.Len(t, newPlan, 0) // Single mode does not scale down
 }
 
 // TestCreatePlanActiveFailoverScale creates a `ActiveFailover` deployment to test the creating of scaling plan.
@@ -664,6 +670,7 @@ func TestCreatePlan(t *testing.T) {
 			},
 			Helper: func(ad *api.ArangoDeployment) {
 				ad.Spec.Mode = api.NewMode(api.DeploymentModeSingle)
+				ad.Status.Members.Single = append(ad.Status.Members.Single, api.MemberStatus{})
 			},
 			ExpectedPlan: []api.Action{},
 		},

pkg/deployment/resources/pod_creator_arangod.go

@@ -191,6 +191,8 @@ func (a *ArangoDContainer) GetEnvs() []core.EnvVar {
 		}
 	}
 
+	envs.Add(true, pod.Topology().Envs(a.member.AsInput())...)
+
 	return envs.GetEnvList()
 }
 

pkg/deployment/rotation/arangod_containers.go

@@ -71,6 +71,7 @@ func containersCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *co
 		return
 	}
 }
+
 func initContainersCompare(deploymentSpec api.DeploymentSpec, group api.ServerGroup, spec, status *core.PodSpec) compareFunc {
 	return func(builder api.ActionBuilder) (mode Mode, plan api.Plan, err error) {
 		gs := deploymentSpec.GetServerGroupSpec(group)

pkg/deployment/topology/const.go

@@ -0,0 +1,23 @@
+//
+// DISCLAIMER
+//
+// Copyright 2020 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 topology
+
+var ArangoDBZone = "ARANGODB_ZONE"