Fix default elasticsearch-data volumeMount configuration

[thbkrkr]

This commit ensures that we take into account the volumes provided by the user to append the default elasticsearch-data volumeMount.

Resolves #6186.

[thbkrkr]

Another approach could be to move the call to AppendDefaultDataVolumeMount in BuildPodTemplateSpec so that we are working with the full list of volumes resulting from merging default ECK volumes and user-provided volumes.

diff --git a/pkg/controller/elasticsearch/nodespec/podspec.go b/pkg/controller/elasticsearch/nodespec/podspec.go
index 52fcda3cd..a012d3f12 100644
--- a/pkg/controller/elasticsearch/nodespec/podspec.go
+++ b/pkg/controller/elasticsearch/nodespec/podspec.go
@@ -110,7 +110,11 @@ func BuildPodTemplateSpec(
                WithReadinessProbe(*NewReadinessProbe()).
                WithAffinity(DefaultAffinity(es.Name)).
                WithEnv(DefaultEnvVars(es.Spec.HTTP, headlessServiceName)...).
-               WithVolumes(volumes...).
+               WithVolumes(volumes...)
+
+       volumeMounts = esvolume.AppendDefaultDataVolumeMount(volumeMounts, volumes)
+
+       builder = builder.
                WithVolumeMounts(volumeMounts...).
                WithInitContainers(initContainers...).

[thbkrkr]

Since there is always an elasticsearch-data volume, either provided by the user (with or without pvc), or configured by default by ECK, I wonder if we should not just add the corresponding volumeMount statically.

diff --git a/pkg/controller/elasticsearch/nodespec/volumes.go b/pkg/controller/elasticsearch/nodespec/volumes.go
index c5da73430..beabe273b 100644
--- a/pkg/controller/elasticsearch/nodespec/volumes.go
+++ b/pkg/controller/elasticsearch/nodespec/volumes.go
@@ -106,6 +106,7 @@ func buildVolumes(
                scriptsVolume.VolumeMount(),
                configVolume.VolumeMount(),
                downwardAPIVolume.VolumeMount(),
+               esvolume.DefaultDataVolumeMount,
        )

[pebrc]

LGTM I did a couple of tests and I think it works as expected. I also think it is safe as use provided mounts will still prevail.

[pebrc]

Let's add a comment here to explain why we are suddenly including the user provided PodTemplate here.