func DeletePodForUpdate()

in controllers/solr_pod_lifecycle_util.go [49:116]
52 lines of code
8 McCabe index (conditional complexity)

func DeletePodForUpdate(ctx context.Context, r *SolrCloudReconciler, instance *solrv1beta1.SolrCloud, pod *corev1.Pod, podHasReplicas bool, logger logr.Logger) (requeueAfterDuration time.Duration, requestInProgress bool, err error) {
	// Before doing anything to the pod, make sure that users cannot send requests to the pod anymore.
	ps := PodStarted
	podStoppedReadinessConditions := map[corev1.PodConditionType]podReadinessConditionChange{
		util.SolrIsNotStoppedReadinessCondition: {
			reason:  PodUpdate,
			message: "Pod is being deleted, traffic to the pod must be stopped",
			status:  false,
		},
		util.SolrReplicasNotEvictedReadinessCondition: {
			// Only set this condition if the condition hasn't been changed since pod start
			// We do not want to over-write future states later down the eviction pipeline
			matchPreviousReason: &ps,
			reason:              EvictingReplicas,
			message:             "Pod is being deleted, ephemeral data must be evicted",
			status:              false,
		},
	}
	if updatedPod, e := EnsurePodReadinessConditions(ctx, r, pod, podStoppedReadinessConditions, logger); e != nil {
		err = e
		return
	} else {
		pod = updatedPod
	}

	// If the pod needs to be drained of replicas (i.e. upgrading a pod with ephemeral storage), do that before deleting the pod
	deletePod := false
	if PodConditionEquals(pod, util.SolrReplicasNotEvictedReadinessCondition, EvictingReplicas) {
		// Only evict pods that contain replicas in the clusterState
		if evictError, canDeletePod, inProgTmp := util.EvictReplicasForPodIfNecessary(ctx, instance, pod, podHasReplicas, "podUpdate", logger); evictError != nil {
			requestInProgress = true
			err = evictError
			logger.Error(err, "Error while evicting replicas on pod", "pod", pod.Name)
		} else if canDeletePod {
			requestInProgress = inProgTmp
			if podHasReplicas {
				// The pod previously had replicas, so loop back in the next reconcile to make sure that the pod doesn't
				// have replicas anymore even if the previous evict command was successful.
				// If there are still replicas, it will start the eviction process again
				requeueAfterDuration = time.Millisecond * 10
			} else {
				deletePod = true
			}
		} else {
			requestInProgress = inProgTmp
			// Try again in 5 seconds if we cannot delete a pod.
			requeueAfterDuration = time.Second * 5
		}
	} else {
		// If a pod has no replicas, then update it when asked to
		deletePod = true
	}

	// Delete the pod
	if deletePod {
		logger.Info("Deleting solr pod for update", "pod", pod.Name)
		err = r.Delete(ctx, pod, client.Preconditions{
			UID: &pod.UID,
		})
		if err != nil {
			logger.Error(err, "Error while killing solr pod for update", "pod", pod.Name)
		}

		// TODO: Create event for the CRD.
	}

	return
}