Merge pull request #152 from arangodb/feature/service-account

Allow customization of serviceAccountName for pods

Author: ewoutp

docs/Manual/Deployment/Kubernetes/DeploymentResource.md

@@ -348,6 +348,14 @@ The default value is `8Gi`.
 This setting is not available for group `coordinators`, `syncmasters` & `syncworkers`
 because servers in these groups do not need persistent storage.
 
+### `spec.<group>.serviceAccountName: string`
+
+This setting specifies the `serviceAccountName` for the `Pods` created
+for each server of this group.
+
+Using an alternative `ServiceAccount` is typically used to separate access rights.
+The ArangoDB deployments do not require any special rights.
+
 ### `spec.<group>.storageClassName: string`
 
 This setting specifies the `storageClass` for the `PersistentVolume`s created

manifests/templates/test/rbac.yaml

@@ -10,7 +10,7 @@ rules:
   resources: ["nodes"]
   verbs: ["list"]
 - apiGroups: [""]
-  resources: ["pods", "services", "persistentvolumes", "persistentvolumeclaims", "secrets"]
+  resources: ["pods", "services", "persistentvolumes", "persistentvolumeclaims", "secrets", "serviceaccounts"]
   verbs: ["*"]
 - apiGroups: ["apps"]
   resources: ["daemonsets"]

pkg/apis/deployment/v1alpha/server_group_spec.go

@@ -28,6 +28,7 @@ import (
 	"k8s.io/apimachinery/pkg/api/resource"
 
 	"github.com/arangodb/kube-arangodb/pkg/util"
+	"github.com/arangodb/kube-arangodb/pkg/util/k8sutil"
 )
 
 // ServerGroupSpec contains the specification for all servers in a specific group (e.g. all agents)
@@ -42,6 +43,8 @@ type ServerGroupSpec struct {
 	Resources v1.ResourceRequirements `json:"resources,omitempty"`
 	// Tolerations specifies the tolerations added to Pods in this group.
 	Tolerations []v1.Toleration `json:"tolerations,omitempty"`
+	// ServiceAccountName specifies the name of the service account used for Pods in this group.
+	ServiceAccountName *string `json:"serviceAccountName,omitempty"`
 }
 
 // GetCount returns the value of count.
@@ -64,6 +67,11 @@ func (s ServerGroupSpec) GetTolerations() []v1.Toleration {
 	return s.Tolerations
 }
 
+// GetServiceAccountName returns the value of serviceAccountName.
+func (s ServerGroupSpec) GetServiceAccountName() string {
+	return util.StringOrDefault(s.ServiceAccountName)
+}
+
 // Validate the given group spec
 func (s ServerGroupSpec) Validate(group ServerGroup, used bool, mode DeploymentMode, env Environment) error {
 	if used {
@@ -86,6 +94,16 @@ func (s ServerGroupSpec) Validate(group ServerGroup, used bool, mode DeploymentM
 		if s.GetCount() > 1 && group == ServerGroupSingle && mode == DeploymentModeSingle {
 			return maskAny(errors.Wrapf(ValidationError, "Invalid count value %d. Expected 1", s.GetCount()))
 		}
+		if name := s.GetServiceAccountName(); name != "" {
+			if err := k8sutil.ValidateOptionalResourceName(name); err != nil {
+				return maskAny(errors.Wrapf(ValidationError, "Invalid serviceAccountName: %s", err))
+			}
+		}
+		if name := s.GetStorageClassName(); name != "" {
+			if err := k8sutil.ValidateOptionalResourceName(name); err != nil {
+				return maskAny(errors.Wrapf(ValidationError, "Invalid storageClassName: %s", err))
+			}
+		}
 	} else if s.GetCount() != 0 {
 		return maskAny(errors.Wrapf(ValidationError, "Invalid count value %d for un-used group. Expected 0", s.GetCount()))
 	}
@@ -145,6 +163,9 @@ func (s *ServerGroupSpec) SetDefaultsFrom(source ServerGroupSpec) {
 	if s.Tolerations == nil {
 		s.Tolerations = source.Tolerations
 	}
+	if s.ServiceAccountName == nil {
+		s.ServiceAccountName = util.NewStringOrNil(source.ServiceAccountName)
+	}
 	setDefaultsFromResourceList(&s.Resources.Limits, source.Resources.Limits)
 	setDefaultsFromResourceList(&s.Resources.Requests, source.Resources.Requests)
 }

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

@@ -597,6 +597,15 @@ func (in *ServerGroupSpec) DeepCopyInto(out *ServerGroupSpec) {
 			(*in)[i].DeepCopyInto(&(*out)[i])
 		}
 	}
+	if in.ServiceAccountName != nil {
+		in, out := &in.ServiceAccountName, &out.ServiceAccountName
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(string)
+			**out = **in
+		}
+	}
 	return
 }
 

pkg/deployment/images.go

@@ -176,8 +176,10 @@ func (ib *imagesBuilder) fetchArangoDBImageIDAndVersion(ctx context.Context, ima
 	tolerations = k8sutil.AddTolerationIfNotFound(tolerations, k8sutil.NewNoExecuteToleration(k8sutil.TolerationKeyNodeNotReady, shortDur))
 	tolerations = k8sutil.AddTolerationIfNotFound(tolerations, k8sutil.NewNoExecuteToleration(k8sutil.TolerationKeyNodeUnreachable, shortDur))
 	tolerations = k8sutil.AddTolerationIfNotFound(tolerations, k8sutil.NewNoExecuteToleration(k8sutil.TolerationKeyNodeAlphaUnreachable, shortDur))
+	serviceAccountName := ""
 
-	if err := k8sutil.CreateArangodPod(ib.KubeCli, true, ib.APIObject, role, id, podName, "", image, "", ib.Spec.GetImagePullPolicy(), "", false, terminationGracePeriod, args, nil, nil, nil, nil, tolerations, "", ""); err != nil {
+	if err := k8sutil.CreateArangodPod(ib.KubeCli, true, ib.APIObject, role, id, podName, "", image, "", ib.Spec.GetImagePullPolicy(), "", false, terminationGracePeriod, args, nil, nil, nil, nil,
+		tolerations, serviceAccountName, "", ""); err != nil {
 		log.Debug().Err(err).Msg("Failed to create image ID pod")
 		return true, maskAny(err)
 	}

pkg/deployment/reconcile/plan_builder.go

@@ -266,6 +266,8 @@ func podNeedsUpgrading(p v1.Pod, spec api.DeploymentSpec, images api.ImageInfoLi
 // When true is returned, a reason for the rotation is already returned.
 func podNeedsRotation(p v1.Pod, apiObject metav1.Object, spec api.DeploymentSpec,
 	group api.ServerGroup, agents api.MemberStatusList, id string) (bool, string) {
+	groupSpec := spec.GetServerGroupSpec(group)
+
 	// Check image pull policy
 	if c, found := k8sutil.GetContainerByName(&p, k8sutil.ServerContainerName); found {
 		if c.ImagePullPolicy != spec.GetImagePullPolicy() {
@@ -274,6 +276,7 @@ func podNeedsRotation(p v1.Pod, apiObject metav1.Object, spec api.DeploymentSpec
 	} else {
 		return true, "Server container not found"
 	}
+
 	// Check arguments
 	/*expectedArgs := createArangodArgs(apiObject, spec, group, agents, id)
 	if len(expectedArgs) != len(c.Args) {
@@ -285,6 +288,11 @@ func podNeedsRotation(p v1.Pod, apiObject metav1.Object, spec api.DeploymentSpec
 		}
 	}*/
 
+	// Check service account
+	if p.Spec.ServiceAccountName != groupSpec.GetServiceAccountName() {
+		return true, "ServiceAccountName changed"
+	}
+
 	return false, ""
 }
 

pkg/deployment/resources/pod_creator.go

@@ -438,6 +438,7 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, group api.Server
 	lifecycleImage := r.context.GetLifecycleImage()
 	terminationGracePeriod := group.DefaultTerminationGracePeriod()
 	tolerations := r.createPodTolerations(group, groupSpec)
+	serviceAccountName := groupSpec.GetServiceAccountName()
 
 	// Update pod name
 	role := group.AsRole()
@@ -500,7 +501,7 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, group api.Server
 		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, spec.GetImagePullPolicy(),
-			engine, requireUUID, terminationGracePeriod, args, env, finalizers, livenessProbe, readinessProbe, tolerations, tlsKeyfileSecretName, rocksdbEncryptionSecretName); err != nil {
+			engine, requireUUID, terminationGracePeriod, args, env, finalizers, livenessProbe, readinessProbe, tolerations, serviceAccountName, tlsKeyfileSecretName, rocksdbEncryptionSecretName); err != nil {
 			return maskAny(err)
 		}
 		log.Debug().Str("pod-name", m.PodName).Msg("Created pod")
@@ -571,7 +572,7 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, group api.Server
 			affinityWithRole = api.ServerGroupDBServers.AsRole()
 		}
 		if err := k8sutil.CreateArangoSyncPod(kubecli, spec.IsDevelopment(), apiObject, role, m.ID, m.PodName, imageInfo.ImageID, lifecycleImage, spec.GetImagePullPolicy(), terminationGracePeriod, args, env,
-			livenessProbe, tolerations, tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole); err != nil {
+			livenessProbe, tolerations, serviceAccountName, tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole); err != nil {
 			return maskAny(err)
 		}
 		log.Debug().Str("pod-name", m.PodName).Msg("Created pod")

pkg/util/k8sutil/pods.go

@@ -390,7 +390,7 @@ func initLifecycleContainer(image string) (v1.Container, error) {
 }
 
 // newPod creates a basic Pod for given settings.
-func newPod(deploymentName, ns, role, id, podName string, finalizers []string, tolerations []v1.Toleration) v1.Pod {
+func newPod(deploymentName, ns, role, id, podName string, finalizers []string, tolerations []v1.Toleration, serviceAccountName string) v1.Pod {
 	hostname := CreatePodHostName(deploymentName, role, id)
 	p := v1.Pod{
 		ObjectMeta: metav1.ObjectMeta{
@@ -399,10 +399,11 @@ func newPod(deploymentName, ns, role, id, podName string, finalizers []string, t
 			Finalizers: finalizers,
 		},
 		Spec: v1.PodSpec{
-			Hostname:      hostname,
-			Subdomain:     CreateHeadlessServiceName(deploymentName),
-			RestartPolicy: v1.RestartPolicyNever,
-			Tolerations:   tolerations,
+			Hostname:           hostname,
+			Subdomain:          CreateHeadlessServiceName(deploymentName),
+			RestartPolicy:      v1.RestartPolicyNever,
+			Tolerations:        tolerations,
+			ServiceAccountName: serviceAccountName,
 		},
 	}
 	return p
@@ -415,10 +416,10 @@ func CreateArangodPod(kubecli kubernetes.Interface, developmentMode bool, deploy
 	role, id, podName, pvcName, image, lifecycleImage string, imagePullPolicy v1.PullPolicy,
 	engine string, requireUUID bool, terminationGracePeriod time.Duration,
 	args []string, env map[string]EnvValue, finalizers []string,
-	livenessProbe *HTTPProbeConfig, readinessProbe *HTTPProbeConfig, tolerations []v1.Toleration,
+	livenessProbe *HTTPProbeConfig, readinessProbe *HTTPProbeConfig, tolerations []v1.Toleration, serviceAccountName string,
 	tlsKeyfileSecretName, rocksdbEncryptionSecretName string) error {
 	// Prepare basic pod
-	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, finalizers, tolerations)
+	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, finalizers, tolerations, serviceAccountName)
 	terminationGracePeriodSeconds := int64(math.Ceil(terminationGracePeriod.Seconds()))
 	p.Spec.TerminationGracePeriodSeconds = &terminationGracePeriodSeconds
 
@@ -516,10 +517,10 @@ func CreateArangodPod(kubecli kubernetes.Interface, developmentMode bool, deploy
 // If the pod already exists, nil is returned.
 // If another error occurs, that error is returned.
 func CreateArangoSyncPod(kubecli kubernetes.Interface, developmentMode bool, deployment APIObject, role, id, podName, image, lifecycleImage string, imagePullPolicy v1.PullPolicy,
-	terminationGracePeriod time.Duration, args []string, env map[string]EnvValue, livenessProbe *HTTPProbeConfig, tolerations []v1.Toleration,
+	terminationGracePeriod time.Duration, args []string, env map[string]EnvValue, livenessProbe *HTTPProbeConfig, tolerations []v1.Toleration, serviceAccountName string,
 	tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole string) error {
 	// Prepare basic pod
-	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, nil, tolerations)
+	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, nil, tolerations, serviceAccountName)
 	terminationGracePeriodSeconds := int64(math.Ceil(terminationGracePeriod.Seconds()))
 	p.Spec.TerminationGracePeriodSeconds = &terminationGracePeriodSeconds