Simplify the condition transition rules (#129)

When the cluster is initializing, either a quorum has not yet been
established, so if the sts isn't ready, we don't change the reason for
etcd not ready, or the cluster has initialized, so we set the status
based on the sts state. This reduces the amount of nesting and repeated
code in the condition/reason checks.

internal/controller/etcdcluster_controller.go

@@ -99,30 +99,26 @@ func (r *EtcdClusterReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 
 	// set cluster readiness condition
 	existingCondition := factory.GetCondition(instance, etcdaenixiov1alpha1.EtcdConditionReady)
-	if existingCondition.Reason == string(etcdaenixiov1alpha1.EtcdCondTypeWaitingForFirstQuorum) {
-		// we should change from "waiting for first quorum establishment" to "StatefulSet ready / not ready"
-		// only after sts gets ready first time
-		if clusterReady {
-			factory.SetCondition(instance, factory.NewCondition(etcdaenixiov1alpha1.EtcdConditionReady).
-				WithStatus(true).
-				WithReason(string(etcdaenixiov1alpha1.EtcdCondTypeStatefulSetReady)).
-				WithMessage(string(etcdaenixiov1alpha1.EtcdReadyCondPosMessage)).
-				Complete())
-		}
-	} else {
-		reason := etcdaenixiov1alpha1.EtcdCondTypeStatefulSetNotReady
-		message := etcdaenixiov1alpha1.EtcdReadyCondNegMessage
-		if clusterReady {
-			reason = etcdaenixiov1alpha1.EtcdCondTypeStatefulSetReady
-			message = etcdaenixiov1alpha1.EtcdReadyCondPosMessage
-		}
+	if existingCondition.Reason == string(etcdaenixiov1alpha1.EtcdCondTypeWaitingForFirstQuorum) && !clusterReady {
+		// if we are still "waiting for first quorum establishment" and the StatefulSet
+		// isn't ready yet, don't update the EtcdConditionReady, but circuit-break.
+		return r.updateStatus(ctx, instance)
+	}
 
-		factory.SetCondition(instance, factory.NewCondition(etcdaenixiov1alpha1.EtcdConditionReady).
-			WithStatus(clusterReady).
-			WithReason(string(reason)).
-			WithMessage(string(message)).
-			Complete())
+	// otherwise, EtcdConditionReady is set to true/false with the reason that the
+	// StatefulSet is or isn't ready.
+	reason := etcdaenixiov1alpha1.EtcdCondTypeStatefulSetNotReady
+	message := etcdaenixiov1alpha1.EtcdReadyCondNegMessage
+	if clusterReady {
+		reason = etcdaenixiov1alpha1.EtcdCondTypeStatefulSetReady
+		message = etcdaenixiov1alpha1.EtcdReadyCondPosMessage
 	}
+
+	factory.SetCondition(instance, factory.NewCondition(etcdaenixiov1alpha1.EtcdConditionReady).
+		WithStatus(clusterReady).
+		WithReason(string(reason)).
+		WithMessage(string(message)).
+		Complete())
 	return r.updateStatus(ctx, instance)
 }