Merge pull request #323 from arangodb/feature/arangodbexporter

ArangoExporter support

Author: neunhoef

pkg/apis/deployment/v1alpha/deployment_spec.go

@@ -61,6 +61,7 @@ type DeploymentSpec struct {
 	TLS            TLSSpec            `json:"tls"`
 	Sync           SyncSpec           `json:"sync"`
 	License        LicenseSpec        `json:"license"`
+	Metrics        MetricsSpec        `json:"metrics"`
 
 	Single       ServerGroupSpec `json:"single"`
 	Agents       ServerGroupSpec `json:"agents"`
@@ -189,6 +190,7 @@ func (s *DeploymentSpec) SetDefaults(deploymentName string) {
 	s.Coordinators.SetDefaults(ServerGroupCoordinators, s.GetMode().HasCoordinators(), s.GetMode())
 	s.SyncMasters.SetDefaults(ServerGroupSyncMasters, s.Sync.IsEnabled(), s.GetMode())
 	s.SyncWorkers.SetDefaults(ServerGroupSyncWorkers, s.Sync.IsEnabled(), s.GetMode())
+	s.Metrics.SetDefaults(deploymentName+"-exporter-jwt-token", s.Authentication.IsAuthenticated())
 	s.Chaos.SetDefaults()
 	s.Bootstrap.SetDefaults(deploymentName)
 }
@@ -228,6 +230,7 @@ func (s *DeploymentSpec) SetDefaultsFrom(source DeploymentSpec) {
 	s.Coordinators.SetDefaultsFrom(source.Coordinators)
 	s.SyncMasters.SetDefaultsFrom(source.SyncMasters)
 	s.SyncWorkers.SetDefaultsFrom(source.SyncWorkers)
+	s.Metrics.SetDefaultsFrom(source.Metrics)
 	s.Chaos.SetDefaultsFrom(source.Chaos)
 	s.Bootstrap.SetDefaultsFrom(source.Bootstrap)
 }
@@ -283,6 +286,9 @@ func (s *DeploymentSpec) Validate() error {
 	if err := s.SyncWorkers.Validate(ServerGroupSyncWorkers, s.Sync.IsEnabled(), s.GetMode(), s.GetEnvironment()); err != nil {
 		return maskAny(err)
 	}
+	if err := s.Metrics.Validate(); err != nil {
+		return maskAny(errors.Wrap(err, "spec.metrics"))
+	}
 	if err := s.Chaos.Validate(); err != nil {
 		return maskAny(errors.Wrap(err, "spec.chaos"))
 	}
@@ -352,5 +358,8 @@ func (s DeploymentSpec) ResetImmutableFields(target *DeploymentSpec) []string {
 	if l := s.SyncWorkers.ResetImmutableFields(ServerGroupSyncWorkers, "syncworkers", &target.SyncWorkers); l != nil {
 		resetFields = append(resetFields, l...)
 	}
+	if l := s.Metrics.ResetImmutableFields("metrics", &target.Metrics); l != nil {
+		resetFields = append(resetFields, l...)
+	}
 	return resetFields
 }

pkg/apis/deployment/v1alpha/metrics_spec.go

@@ -0,0 +1,105 @@
+//
+// DISCLAIMER
+//
+// Copyright 2018 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 v1alpha
+
+import (
+	"github.com/arangodb/kube-arangodb/pkg/util"
+	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
+)
+
+// MetricsAuthenticationSpec contains spec for authentication with arangodb
+type MetricsAuthenticationSpec struct {
+	// JWTTokenSecretName contains the name of the JWT kubernetes secret used for authentication
+	JWTTokenSecretName *string `json:"jwtTokenSecretName,omitempty"`
+}
+
+// MetricsSpec contains spec for arangodb exporter
+type MetricsSpec struct {
+	Enabled        *bool                     `json:"enabled,omitempty"`
+	Image          *string                   `json:"image,omitempty"`
+	Authentication MetricsAuthenticationSpec `json:"authentication,omitempty"`
+}
+
+// IsEnabled returns whether metrics are enabled or not
+func (s *MetricsSpec) IsEnabled() bool {
+	return util.BoolOrDefault(s.Enabled, false)
+}
+
+// HasImage returns whether a image was specified or not
+func (s *MetricsSpec) HasImage() bool {
+	return s.Image != nil
+}
+
+// GetImage returns the Image or empty string
+func (s *MetricsSpec) GetImage() string {
+	return util.StringOrDefault(s.Image)
+}
+
+// SetDefaults sets default values
+func (s *MetricsSpec) SetDefaults(defaultTokenName string, isAuthenticated bool) {
+	if s.Enabled == nil {
+		s.Enabled = util.NewBool(false)
+	}
+	if s.GetJWTTokenSecretName() == "" {
+		s.Authentication.JWTTokenSecretName = util.NewString(defaultTokenName)
+	}
+}
+
+// GetJWTTokenSecretName returns the token secret name or empty string
+func (s *MetricsSpec) GetJWTTokenSecretName() string {
+	return util.StringOrDefault(s.Authentication.JWTTokenSecretName)
+}
+
+// HasJWTTokenSecretName returns true if a secret name was specified
+func (s *MetricsSpec) HasJWTTokenSecretName() bool {
+	return s.Authentication.JWTTokenSecretName != nil
+}
+
+// SetDefaultsFrom fills unspecified fields with a value from given source spec.
+func (s *MetricsSpec) SetDefaultsFrom(source MetricsSpec) {
+	if s.Enabled == nil {
+		s.Enabled = util.NewBoolOrNil(source.Enabled)
+	}
+	if s.Image == nil {
+		s.Image = util.NewStringOrNil(source.Image)
+	}
+	if s.Authentication.JWTTokenSecretName == nil {
+		s.Authentication.JWTTokenSecretName = util.NewStringOrNil(source.Authentication.JWTTokenSecretName)
+	}
+}
+
+// Validate the given spec
+func (s *MetricsSpec) Validate() error {
+
+	if s.HasJWTTokenSecretName() {
+		if err := k8sutil.ValidateResourceName(s.GetJWTTokenSecretName()); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// ResetImmutableFields replaces all immutable fields in the given target with values from the source spec.
+func (s MetricsSpec) ResetImmutableFields(fieldPrefix string, target *MetricsSpec) []string {
+	return nil
+}

pkg/apis/deployment/v1alpha/server_group.go

@@ -130,3 +130,13 @@ func (g ServerGroup) IsArangosync() bool {
 		return false
 	}
 }
+
+// IsExportMetrics return true when the group can be used with the arangodbexporter
+func (g ServerGroup) IsExportMetrics() bool {
+	switch g {
+	case ServerGroupCoordinators, ServerGroupDBServers, ServerGroupSingle:
+		return true
+	default:
+		return false
+	}
+}

pkg/apis/deployment/v1alpha/zz_generated.deepcopy.go

@@ -198,7 +198,7 @@ func (ib *imagesBuilder) fetchArangoDBImageIDAndVersion(ctx context.Context, ima
 		}
 	}
 	if err := k8sutil.CreateArangodPod(ib.KubeCli, true, ib.APIObject, role, id, podName, "", image, "", "", ib.Spec.GetImagePullPolicy(), "", false, terminationGracePeriod, args, env, nil, nil, nil,
-		tolerations, serviceAccountName, "", "", "", nil, "", v1.ResourceRequirements{}); err != nil {
+		tolerations, serviceAccountName, "", "", "", nil, "", v1.ResourceRequirements{}, nil); err != nil {
 		log.Debug().Err(err).Msg("Failed to create image ID pod")
 		return true, maskAny(err)
 	}

pkg/deployment/images.go

@@ -343,6 +343,24 @@ func podNeedsRotation(log zerolog.Logger, p v1.Pod, apiObject metav1.Object, spe
 		return false, "Server Image not found"
 	}
 
+	if group.IsExportMetrics() {
+		e, hasExporter := k8sutil.GetContainerByName(&p, k8sutil.ExporterContainerName)
+
+		if spec.Metrics.IsEnabled() {
+			if !hasExporter {
+				return true, "Exporter configuration changed"
+			}
+
+			if spec.Metrics.HasImage() {
+				if e.Image != spec.Metrics.GetImage() {
+					return true, "Exporter image changed"
+				}
+			}
+		} else if hasExporter {
+			return true, "Exporter was disabled"
+		}
+	}
+
 	// Check arguments
 	expectedArgs := strings.Join(context.GetExpectedPodArguments(apiObject, spec, group, status.Members.Agents, id, podImageInfo.ArangoDBVersion), " ")
 	actualArgs := strings.Join(getContainerArgs(c), " ")

pkg/deployment/reconcile/plan_builder.go

@@ -329,6 +329,30 @@ func createArangoSyncArgs(apiObject metav1.Object, spec api.DeploymentSpec, grou
 	return args
 }
 
+func createExporterArgs(isSecure bool) []string {
+	tokenpath := filepath.Join(k8sutil.ExporterJWTVolumeMountDir, constants.SecretKeyToken)
+	options := make([]optionPair, 0, 64)
+	options = append(options,
+		optionPair{"--arangodb.jwt-file", tokenpath},
+		optionPair{"--arangodb.endpoint", "http://localhost:" + strconv.Itoa(k8sutil.ArangoPort)},
+	)
+	keyPath := filepath.Join(k8sutil.TLSKeyfileVolumeMountDir, constants.SecretTLSKeyfile)
+	if isSecure {
+		options = append(options,
+			optionPair{"--ssl.keyfile", keyPath},
+		)
+	}
+	args := make([]string, 0, 2+len(options))
+	sort.Slice(options, func(i, j int) bool {
+		return options[i].CompareTo(options[j]) < 0
+	})
+	for _, o := range options {
+		args = append(args, o.Key+"="+o.Value)
+	}
+
+	return args
+}
+
 // createLivenessProbe creates configuration for a liveness probe of a server in the given group.
 func (r *Resources) createLivenessProbe(spec api.DeploymentSpec, group api.ServerGroup) (*k8sutil.HTTPProbeConfig, error) {
 	groupspec := spec.GetServerGroupSpec(group)
@@ -497,6 +521,16 @@ func (r *Resources) createPodTolerations(group api.ServerGroup, groupSpec api.Se
 	return tolerations
 }
 
+func createExporterLivenessProbe(isSecure bool) *k8sutil.HTTPProbeConfig {
+	probeCfg := &k8sutil.HTTPProbeConfig{
+		LocalPath: "/",
+		Port:      k8sutil.ArangoExporterPort,
+		Secure:    isSecure,
+	}
+
+	return probeCfg
+}
+
 // createPodForMember creates all Pods listed in member status
 func (r *Resources) createPodForMember(spec api.DeploymentSpec, memberID string, imageNotFoundOnce *sync.Once) error {
 	kubecli := r.context.GetKubeCli()
@@ -604,12 +638,29 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, memberID string,
 			}
 		}
 
+		var exporter *k8sutil.ArangodbExporterContainerConf
+
+		if spec.Metrics.IsEnabled() {
+			if group.IsExportMetrics() {
+				image := spec.GetImage()
+				if spec.Metrics.HasImage() {
+					image = spec.Metrics.GetImage()
+				}
+				exporter = &k8sutil.ArangodbExporterContainerConf{
+					Args:               createExporterArgs(spec.IsSecure()),
+					JWTTokenSecretName: spec.Metrics.GetJWTTokenSecretName(),
+					LivenessProbe:      createExporterLivenessProbe(spec.IsSecure()),
+					Image:              image,
+				}
+			}
+		}
+
 		engine := spec.GetStorageEngine().AsArangoArgument()
 		requireUUID := group == api.ServerGroupDBServers && m.IsInitialized
 		finalizers := r.createPodFinalizers(group)
 		if err := k8sutil.CreateArangodPod(kubecli, spec.IsDevelopment(), apiObject, role, m.ID, m.PodName, m.PersistentVolumeClaimName, imageInfo.ImageID, lifecycleImage, alpineImage, spec.GetImagePullPolicy(),
 			engine, requireUUID, terminationGracePeriod, args, env, finalizers, livenessProbe, readinessProbe, tolerations, serviceAccountName, tlsKeyfileSecretName, rocksdbEncryptionSecretName,
-			clusterJWTSecretName, groupSpec.GetNodeSelector(), groupSpec.PriorityClassName, groupSpec.Resources); err != nil {
+			clusterJWTSecretName, groupSpec.GetNodeSelector(), groupSpec.PriorityClassName, groupSpec.Resources, exporter); err != nil {
 			return maskAny(err)
 		}
 		log.Debug().Str("pod-name", m.PodName).Msg("Created pod")

pkg/deployment/resources/pod_creator.go

@@ -55,6 +55,12 @@ func (r *Resources) EnsureSecrets() error {
 		if err := r.ensureTokenSecret(secrets, spec.Authentication.GetJWTSecretName()); err != nil {
 			return maskAny(err)
 		}
+
+		if spec.Metrics.IsEnabled() {
+			if err := r.ensureExporterTokenSecret(secrets, spec.Metrics.GetJWTTokenSecretName(), spec.Authentication.GetJWTSecretName()); err != nil {
+				return maskAny(err)
+			}
+		}
 	}
 	if spec.IsSecure() {
 		counterMetric.Inc()
@@ -110,6 +116,32 @@ func (r *Resources) ensureTokenSecret(secrets k8sutil.SecretInterface, secretNam
 	return nil
 }
 
+// ensureExporterTokenSecret checks if a secret with given name exists in the namespace
+// of the deployment. If not, it will add such a secret with correct access.
+func (r *Resources) ensureExporterTokenSecret(secrets k8sutil.SecretInterface, tokenSecretName, secretSecretName string) error {
+	if _, err := secrets.Get(tokenSecretName, metav1.GetOptions{}); k8sutil.IsNotFound(err) {
+		// Secret not found, create it
+		claims := map[string]interface{}{
+			"iss":           "arangodb",
+			"server_id":     "exporter",
+			"allowed_paths": []string{"/_admin/statistics", "/_admin/statistics-description"},
+		}
+		// Create secret
+		owner := r.context.GetAPIObject().AsOwner()
+		if err := k8sutil.CreateJWTFromSecret(secrets, tokenSecretName, secretSecretName, claims, &owner); k8sutil.IsAlreadyExists(err) {
+			// Secret added while we tried it also
+			return nil
+		} else if err != nil {
+			// Failed to create secret
+			return maskAny(err)
+		}
+	} else if err != nil {
+		// Failed to get secret for other reasons
+		return maskAny(err)
+	}
+	return nil
+}
+
 // ensureTLSCACertificateSecret checks if a secret with given name exists in the namespace
 // of the deployment. If not, it will add such a secret with a generated CA certificate.
 func (r *Resources) ensureTLSCACertificateSecret(secrets k8sutil.SecretInterface, spec api.TLSSpec) error {

pkg/deployment/resources/secrets.go

@@ -27,6 +27,7 @@ const (
 	ArangoPort           = 8529
 	ArangoSyncMasterPort = 8629
 	ArangoSyncWorkerPort = 8729
+	ArangoExporterPort   = 9101
 
 	// K8s constants
 	ClusterIPNone                      = "None"