supplement observables with desired replicas calculation, decouple co…

…nfigmap templating from reconciliation logic

internal/controller/etcdcluster_controller.go

@@ -91,6 +91,7 @@ func (r *EtcdClusterReconciler) Reconcile(ctx context.Context, req ctrl.Request)
  }
 
  state := observables{}
+ state.instance = instance
 
  // create two services and the pdb
  err = r.ensureUnconditionalObjects(ctx, instance)
@@ -112,11 +113,8 @@ func (r *EtcdClusterReconciler) Reconcile(ctx context.Context, req ctrl.Request)
  }
  state.endpointsFound = clusterClient != nil && singleClients != nil
 
- if !state.endpointsFound {
- if !state.stsExists {
- // TODO: happy path for new cluster creation
- log.Debug(ctx, "happy path for new cluster creation (not yet implemented)")
- }
+ if clusterClient != nil {
+ state.endpoints = clusterClient.Endpoints()
  }
 
  // fetch PVCs
@@ -125,6 +123,20 @@ func (r *EtcdClusterReconciler) Reconcile(ctx context.Context, req ctrl.Request)
  return ctrl.Result{}, err
  }
 
+ if !state.endpointsFound {
+ if !state.stsExists {
+ cm := factory.TemplateClusterStateConfigMap(instance, "new", state.desiredReplicas())
+ err := ctrl.SetControllerReference(instance, cm, r.Scheme)
+ if err != nil {
+ return ctrl.Result{}, err
+ }
+ err = r.patchOrCreateObject(ctx, cm)
+ if err != nil {
+ return ctrl.Result{}, err
+ }
+ }
+ }
+
  // get status of every endpoint and member list from every endpoint
  state.etcdStatuses = make([]etcdStatus, len(singleClients))
  {
@@ -667,3 +679,14 @@ func (r *EtcdClusterReconciler) ensureUnconditionalObjects(ctx context.Context,
  }
  return nil
 }
+
+func (r *EtcdClusterReconciler) patchOrCreateObject(ctx context.Context, obj client.Object) error {
+ err := r.Patch(ctx, obj, client.Apply, &client.PatchOptions{FieldManager: "etcd-operator"}, client.ForceOwnership)
+ if err == nil {
+ return nil
+ }
+ if client.IgnoreNotFound(err) == nil {
+ err = r.Create(ctx, obj)
+ }
+ return err
+}

internal/controller/factory/configmap.go

@@ -19,6 +19,7 @@ package factory
 import (
  "context"
  "fmt"
+ "strings"
 
  etcdaenixiov1alpha1 "github.com/aenix-io/etcd-operator/api/v1alpha1"
  "github.com/aenix-io/etcd-operator/internal/log"
@@ -29,6 +30,36 @@ import (
  "sigs.k8s.io/controller-runtime/pkg/client"
 )
 
+func TemplateClusterStateConfigMap(cluster *etcdaenixiov1alpha1.EtcdCluster, state string, replicas int) *corev1.ConfigMap {
+
+ initialClusterMembers := make([]string, replicas)
+ clusterService := fmt.Sprintf("%s.%s.svc:2380", GetHeadlessServiceName(cluster), cluster.Namespace)
+ for i := 0; i < replicas; i++ {
+ podName := fmt.Sprintf("%s-%d", cluster.Name, i)
+ initialClusterMembers[i] = fmt.Sprintf("%s=https://%s.%s",
+ podName, podName, clusterService,
+ )
+ }
+ initialCluster := strings.Join(initialClusterMembers, ",")
+
+ configMap := &corev1.ConfigMap{
+ TypeMeta: metav1.TypeMeta{
+ APIVersion: "v1",
+ Kind: "ConfigMap",
+ },
+ ObjectMeta: metav1.ObjectMeta{
+ Name: fmt.Sprintf("%s-cluster-state", cluster.Name),
+ Namespace: cluster.Namespace,
+ },
+ Data: map[string]string{
+ "ETCD_INITIAL_CLUSTER_STATE": state,
+ "ETCD_INITIAL_CLUSTER": initialCluster,
+ "ETCD_INITIAL_CLUSTER_TOKEN": fmt.Sprintf("%s-%s", cluster.Name, cluster.Namespace),
+ },
+ }
+ return configMap
+}
+
 func GetClusterStateConfigMapName(cluster *etcdaenixiov1alpha1.EtcdCluster) string {
  return cluster.Name + "-cluster-state"
 }

internal/controller/observables.go

@@ -6,6 +6,7 @@ import (
  "strings"
  "sync"
 
+ "github.com/aenix-io/etcd-operator/api/v1alpha1"
  "github.com/aenix-io/etcd-operator/pkg/set"
  clientv3 "go.etcd.io/etcd/client/v3"
  appsv1 "k8s.io/api/apps/v1"
@@ -25,13 +26,13 @@ type etcdStatus struct {
 // observables stores observations that the operator can make about
 // states of objects in kubernetes
 type observables struct {
+ instance *v1alpha1.EtcdCluster
  statefulSet appsv1.StatefulSet
  stsExists bool
- endpoints corev1.Endpoints
+ endpoints []string
  endpointsFound bool
  etcdStatuses []etcdStatus
  clusterID uint64
- _ int
  pvcs []corev1.PersistentVolumeClaim
 }
 
@@ -99,33 +100,74 @@ func (s *etcdStatus) fill(ctx context.Context, c *clientv3.Client) {
  wg.Wait()
 }
 
-func (o *observables) pvcMaxIndex() int {
- idx := -1
+func (o *observables) pvcMaxIndex() (max int) {
+ max = -1
  for i := range o.pvcs {
- subs := strings.Split(o.pvcs[i].Name, "-")
- index, err := strconv.Atoi(subs[len(subs)-1])
+ tokens := strings.Split(o.pvcs[i].Name, "-")
+ index, err := strconv.Atoi(tokens[len(tokens)-1])
  if err != nil {
  continue
  }
- if index > idx {
- idx = index
+ if index > max {
+ max = index
  }
  }
- return idx
+ return max
+}
+
+func (o *observables) endpointMaxIndex() (max int) {
+ for i := range o.endpoints {
+ tokens := strings.Split(o.endpoints[i], ":")
+ if len(tokens) < 2 {
+ continue
+ }
+ tokens = strings.Split(tokens[len(tokens)-2], "-")
+ index, err := strconv.Atoi(tokens[len(tokens)-1])
+ if err != nil {
+ continue
+ }
+ if index > max {
+ max = index
+ }
+ }
+ return max
 }
 
 // TODO: make a real function to determine the right number of replicas.
 // Hint: if ClientURL in the member list is absent, the member has not yet
 // started, but if the name field is populated, this is a member of the
 // initial cluster. If the name field is empty, this member has just been
 // added with etcdctl member add (or equivalent API call).
-func (o *observables) _() int {
+func (o *observables) desiredReplicas() (max int) {
+ max = -1
  if o.etcdStatuses != nil {
  for i := range o.etcdStatuses {
  if o.etcdStatuses[i].memberList != nil {
- return len(o.etcdStatuses[i].memberList.Members)
+ for j := range o.etcdStatuses[i].memberList.Members {
+ tokens := strings.Split(o.etcdStatuses[i].memberList.Members[j].Name, "-")
+ index, err := strconv.Atoi(tokens[len(tokens)-1])
+ if err != nil {
+ continue
+ }
+ if index > max {
+ max = index
+ }
+ }
  }
  }
  }
- return 0
+ if max > -1 {
+ return max + 1
+ }
+
+ if epMax := o.endpointMaxIndex(); epMax > max {
+ max = epMax
+ }
+ if pvcMax := o.pvcMaxIndex(); pvcMax > max {
+ max = pvcMax
+ }
+ if max == -1 {
+ return int(*o.instance.Spec.Replicas)
+ }
+ return max + 1
 }

site/content/en/docs/v0.4/reference/api.md

@@ -167,8 +167,8 @@ _Appears in:_
 
 | Field | Description | Default | Validation |
 | --- | --- | --- | --- |
-| `minAvailable` _[IntOrString](#intorstring)_ | MinAvailable describes minimum ready replicas. If both are empty, controller will implicitly<br />calculate MaxUnavailable based on number of replicas<br />Mutually exclusive with MaxUnavailable. | | |
-| `maxUnavailable` _[IntOrString](#intorstring)_ | MinAvailable describes maximum not ready replicas. If both are empty, controller will implicitly<br />calculate MaxUnavailable based on number of replicas<br />Mutually exclusive with MinAvailable | | |
+| `minAvailable` _[IntOrString](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.30.0/#intorstring-intstr-util)_ | MinAvailable describes minimum ready replicas. If both are empty, controller will implicitly<br />calculate MaxUnavailable based on number of replicas<br />Mutually exclusive with MaxUnavailable. | | |
+| `maxUnavailable` _[IntOrString](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.30.0/#intorstring-intstr-util)_ | MinAvailable describes maximum not ready replicas. If both are empty, controller will implicitly<br />calculate MaxUnavailable based on number of replicas<br />Mutually exclusive with MinAvailable | | |
 
 
 #### PodTemplate