Merge pull request #311 from arangodb/feature/node-selector

NodeSelector

Author: neunhoef

docs/Manual/Deployment/Kubernetes/DeploymentResource.md

@@ -348,7 +348,7 @@ for `spec.mode: Single` and `2` for `spec.mode: ActiveFailover`).
 For the `syncworkers` group, it is highly recommended to use the same number
 as for the `dbservers` group.
 
-### `spec.<group>.args: [string]`
+### `spec.<group>.args: []string`
 
 This setting specifies additional commandline arguments passed to all servers of this group.
 The default value is an empty array.
@@ -389,7 +389,7 @@ for each server of this group.
 This setting is not available for group `coordinators`, `syncmasters` & `syncworkers`
 because servers in these groups do not need persistent storage.
 
-### `spec.<group>.tolerations: [Toleration]`
+### `spec.<group>.tolerations: []Toleration`
 
 This setting specifies the `tolerations` for the `Pod`s created
 for each server of this group.
@@ -401,3 +401,9 @@ By default, suitable tolerations are set for the following keys with the `NoExec
 - `node.alpha.kubernetes.io/unreachable` (will be removed in future version)
 
 For more information on tolerations, consult the [Kubernetes documentation](https://kubernetes.io/docs/concepts/configuration/taint-and-toleration/).
+
+### `spec.<group>.nodeSelector: map[string]string`
+
+This setting specifies a set of labels to be used as `nodeSelector` for Pods of this node.
+
+For more information on node selectors, consult the [Kubernetes documentation](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/).

pkg/apis/deployment/v1alpha/server_group_spec.go

@@ -49,13 +49,20 @@ type ServerGroupSpec struct {
 	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"`
+	// NodeSelector speficies a set of selectors for nodes
+	NodeSelector map[string]string `json:"nodeSelector,omitempty"`
 }
 
 // GetCount returns the value of count.
 func (s ServerGroupSpec) GetCount() int {
 	return util.IntOrDefault(s.Count)
 }
 
+// GetNodeSelector returns the selectors for nodes of this group
+func (s ServerGroupSpec) GetNodeSelector() map[string]string {
+	return s.NodeSelector
+}
+
 // GetArgs returns the value of args.
 func (s ServerGroupSpec) GetArgs() []string {
 	return s.Args
@@ -194,6 +201,9 @@ func (s *ServerGroupSpec) SetDefaultsFrom(source ServerGroupSpec) {
 	if s.ServiceAccountName == nil {
 		s.ServiceAccountName = util.NewStringOrNil(source.ServiceAccountName)
 	}
+	if s.NodeSelector == nil {
+		s.NodeSelector = source.NodeSelector
+	}
 	setDefaultsFromResourceList(&s.Resources.Limits, source.Resources.Limits)
 	setDefaultsFromResourceList(&s.Resources.Requests, source.Resources.Requests)
 }

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, "", ""); err != nil {
+		tolerations, serviceAccountName, "", "", nil); err != nil {
 		log.Debug().Err(err).Msg("Failed to create image ID pod")
 		return true, maskAny(err)
 	}

pkg/deployment/images.go

@@ -537,7 +537,8 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, memberID string,
 		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); err != nil {
+			engine, requireUUID, terminationGracePeriod, args, env, finalizers, livenessProbe, readinessProbe, tolerations, serviceAccountName, tlsKeyfileSecretName, rocksdbEncryptionSecretName,
+			groupSpec.GetNodeSelector()); err != nil {
 			return maskAny(err)
 		}
 		log.Debug().Str("pod-name", m.PodName).Msg("Created pod")
@@ -614,7 +615,7 @@ func (r *Resources) createPodForMember(spec api.DeploymentSpec, memberID string,
 			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, serviceAccountName, tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole); err != nil {
+			livenessProbe, tolerations, serviceAccountName, tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole, groupSpec.GetNodeSelector()); err != nil {
 			return maskAny(err)
 		}
 		log.Debug().Str("pod-name", m.PodName).Msg("Created pod")

pkg/deployment/resources/pod_creator.go

@@ -389,7 +389,7 @@ 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, serviceAccountName string) v1.Pod {
+func newPod(deploymentName, ns, role, id, podName string, finalizers []string, tolerations []v1.Toleration, serviceAccountName string, nodeSelector map[string]string) v1.Pod {
 	hostname := CreatePodHostName(deploymentName, role, id)
 	p := v1.Pod{
 		ObjectMeta: metav1.ObjectMeta{
@@ -403,6 +403,7 @@ func newPod(deploymentName, ns, role, id, podName string, finalizers []string, t
 			RestartPolicy:      v1.RestartPolicyNever,
 			Tolerations:        tolerations,
 			ServiceAccountName: serviceAccountName,
+			NodeSelector:       nodeSelector,
 		},
 	}
 	return p
@@ -416,9 +417,9 @@ func CreateArangodPod(kubecli kubernetes.Interface, developmentMode bool, deploy
 	engine string, requireUUID bool, terminationGracePeriod time.Duration,
 	args []string, env map[string]EnvValue, finalizers []string,
 	livenessProbe *HTTPProbeConfig, readinessProbe *HTTPProbeConfig, tolerations []v1.Toleration, serviceAccountName string,
-	tlsKeyfileSecretName, rocksdbEncryptionSecretName string) error {
+	tlsKeyfileSecretName, rocksdbEncryptionSecretName string, nodeSelector map[string]string) error {
 	// Prepare basic pod
-	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, finalizers, tolerations, serviceAccountName)
+	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, finalizers, tolerations, serviceAccountName, nodeSelector)
 	terminationGracePeriodSeconds := int64(math.Ceil(terminationGracePeriod.Seconds()))
 	p.Spec.TerminationGracePeriodSeconds = &terminationGracePeriodSeconds
 
@@ -519,9 +520,9 @@ func CreateArangodPod(kubecli kubernetes.Interface, developmentMode bool, deploy
 // 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, serviceAccountName string,
-	tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole string) error {
+	tlsKeyfileSecretName, clientAuthCASecretName, masterJWTSecretName, clusterJWTSecretName, affinityWithRole string, nodeSelector map[string]string) error {
 	// Prepare basic pod
-	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, nil, tolerations, serviceAccountName)
+	p := newPod(deployment.GetName(), deployment.GetNamespace(), role, id, podName, nil, tolerations, serviceAccountName, nodeSelector)
 	terminationGracePeriodSeconds := int64(math.Ceil(terminationGracePeriod.Seconds()))
 	p.Spec.TerminationGracePeriodSeconds = &terminationGracePeriodSeconds