[Feature] Topology Discovery (#835)

CHANGELOG.md

@@ -6,6 +6,7 @@
 - Add new admin commands to fetch agency dump and agency state
 - Add Graceful shutdown as finalizer (supports kubectl delete)
 - Add Watch to Lifecycle command
+- Add Topology Discovery
 
 ## [1.2.4](https://github.com/arangodb/kube-arangodb/tree/1.2.4) (2021-10-22)
 - Replace `beta.kubernetes.io/arch` Pod label with `kubernetes.io/arch` using Silent Rotation

pkg/deployment/reconcile/plan_builder_high.go

@@ -89,6 +89,7 @@ func createHighPlan(ctx context.Context, log zerolog.Logger, apiObject k8sutil.A
 		ApplyIfEmpty(createCleanOutPlan).
 		ApplyIfEmpty(updateMemberUpdateConditionsPlan).
 		ApplyIfEmpty(updateMemberRotationConditionsPlan).
+		ApplyIfEmpty(createTopologyMemberUpdatePlan).
 		ApplyIfEmpty(createTopologyMemberConditionPlan).
 		Plan(), true
 }

pkg/deployment/reconcile/plan_builder_topology.community.go

@@ -37,6 +37,12 @@ func createTopologyEnablementPlan(ctx context.Context,
 	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext) api.Plan {
 	return nil
 }
+func createTopologyMemberUpdatePlan(ctx context.Context,
+	log zerolog.Logger, apiObject k8sutil.APIObject,
+	spec api.DeploymentSpec, status api.DeploymentStatus,
+	cachedStatus inspectorInterface.Inspector, context PlanBuilderContext) api.Plan {
+	return nil
+}
 
 func createTopologyMemberConditionPlan(ctx context.Context,
 	log zerolog.Logger, apiObject k8sutil.APIObject,

pkg/deployment/rotation/arangod_containers.go

@@ -26,6 +26,8 @@ package rotation
 import (
 	"strings"
 
+	"github.com/arangodb/kube-arangodb/pkg/deployment/topology"
+
 	"k8s.io/apimachinery/pkg/api/equality"
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
@@ -50,15 +52,26 @@ func containersCompare(_ api.DeploymentSpec, _ api.ServerGroup, spec, status *co
 		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) {
-						continue
-					}
+					if isOnlyLogLevelChanged(ac.Command, bc.Command) {
+						plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerArgsLogLevelUpdate).
+							AddParam(ContainerName, ac.Name))
 
-					plan = append(plan, builder.NewAction(api.ActionTypeRuntimeContainerArgsLogLevelUpdate).
-						AddParam(ContainerName, ac.Name))
+						bc.Command = ac.Command
+						mode = mode.And(InPlaceRotation)
+					}
 
-					bc.Command = ac.Command
-					mode = mode.And(InPlaceRotation)
+					if !equality.Semantic.DeepEqual(ac.Env, bc.Env) {
+						if areEnvsEqual(ac.Env, bc.Env, func(a, b map[string]core.EnvVar) (map[string]core.EnvVar, map[string]core.EnvVar) {
+							if _, ok := a[topology.ArangoDBZone]; !ok {
+								delete(b, topology.ArangoDBZone)
+							}
+
+							return a, b
+						}) {
+							bc.Env = ac.Env
+							mode = mode.And(SilentRotation)
+						}
+					}
 				} else {
 					if ac.Image != bc.Image {
 						// Image changed
@@ -162,3 +175,24 @@ func internalContainerLifecycleCompare(spec, status *core.Container) Mode {
 
 	return SkippedRotation
 }
+
+func areEnvsEqual(a, b []core.EnvVar, rules ...func(a, b map[string]core.EnvVar) (map[string]core.EnvVar, map[string]core.EnvVar)) bool {
+	am := getEnvs(a)
+	bm := getEnvs(b)
+
+	for _, r := range rules {
+		am, bm = r(am, bm)
+	}
+
+	return equality.Semantic.DeepEqual(am, bm)
+}
+
+func getEnvs(e []core.EnvVar) map[string]core.EnvVar {
+	m := map[string]core.EnvVar{}
+
+	for _, q := range e {
+		m[q.Name] = q
+	}
+
+	return m
+}

pkg/deployment/rotation/arangod_test.go

@@ -25,6 +25,8 @@ package rotation
 import (
 	"testing"
 
+	"github.com/arangodb/kube-arangodb/pkg/deployment/topology"
+
 	core "k8s.io/api/core/v1"
 )
 
@@ -177,3 +179,150 @@ func Test_ArangoD_Affinity(t *testing.T) {
 
 	runTestCases(t)(testCases...)
 }
+
+func Test_ArangoD_Labels(t *testing.T) {
+	testCases := []TestCase{
+		{
+			name: "Add label",
+
+			spec: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{}
+			}),
+
+			status: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{
+					"A": "B",
+				}
+			}),
+
+			expectedMode: SkippedRotation,
+		},
+		{
+			name: "Remove label",
+
+			spec: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{
+					"A": "B",
+				}
+			}),
+
+			status: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{}
+			}),
+
+			expectedMode: SkippedRotation,
+		},
+		{
+			name: "Change label",
+
+			spec: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{
+					"A": "A",
+				}
+			}),
+
+			status: buildPodSpec(func(pod *core.PodTemplateSpec) {
+				pod.Labels = map[string]string{
+					"A": "B",
+				}
+			}),
+
+			expectedMode: SkippedRotation,
+		},
+	}
+
+	runTestCases(t)(testCases...)
+}
+
+func Test_ArangoD_Envs_Zone(t *testing.T) {
+	testCases := []TestCase{
+		{
+			name: "Add Zone env",
+
+			spec: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{}
+			})),
+
+			status: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "A",
+					},
+				}
+			})),
+
+			expectedMode: SilentRotation,
+		},
+		{
+			name: "Remove Zone env",
+
+			spec: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "A",
+					},
+				}
+			})),
+
+			status: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{}
+			})),
+
+			expectedMode: GracefulRotation,
+		},
+		{
+			name: "Update Zone env",
+
+			spec: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "A",
+					},
+				}
+			})),
+
+			status: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "B",
+					},
+				}
+			})),
+
+			expectedMode: GracefulRotation,
+		},
+		{
+			name: "Update other env",
+
+			spec: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  "Q",
+						Value: "A",
+					},
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "A",
+					},
+				}
+			})),
+
+			status: buildPodSpec(addContainer("server", func(c *core.Container) {
+				c.Env = []core.EnvVar{
+					{
+						Name:  topology.ArangoDBZone,
+						Value: "A",
+					},
+				}
+			})),
+
+			expectedMode: GracefulRotation,
+		},
+	}
+
+	runTestCases(t)(testCases...)
+}

pkg/deployment/rotation/compare.go

@@ -21,6 +21,8 @@
 package rotation
 
 import (
+	"encoding/json"
+
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1"
 	"github.com/arangodb/kube-arangodb/pkg/deployment/resources"
 	"github.com/rs/zerolog"
@@ -88,10 +90,13 @@ func compare(log zerolog.Logger, deploymentSpec api.DeploymentSpec, member api.M
 	}
 
 	if spec.RotationNeeded(newStatus) {
+		specData, _ := json.Marshal(spec)
+		statusData, _ := json.Marshal(newStatus)
+
 		log.Info().Str("before", spec.PodSpecChecksum).
 			Str("id", member.ID).
-			Interface("spec", spec).
-			Interface("status", newStatus).
+			Str("spec", string(specData)).
+			Str("status", string(statusData)).
 			Msg("Pod needs rotation - templates does not match")
 
 		return GracefulRotation, nil, nil