style: tighten comments

Trim redundant/restating comments and cut wording in the
shouldInjectBarmanSidecar doc-comment without dropping any of the
non-obvious reasoning it documents.

Signed-off-by: Marco Nenciarini <marco.nenciarini@enterprisedb.com>

internal/cnpgi/instance/identity_test.go

@@ -39,8 +39,7 @@ var _ = Describe("IdentityImplementation", func() {
 				serviceTypes = append(serviceTypes, capability.GetService().GetType())
 			}
 
-			// The instance sidecar now runs the phase-0 restore in-process, so it must
+			// Runs the phase-0 restore in-process now, hence TYPE_RESTORE_JOB below.
-			// advertise TYPE_RESTORE_JOB alongside the services it already served.
 			Expect(serviceTypes).To(ConsistOf(
 				identity.PluginCapability_Service_TYPE_WAL_SERVICE,
 				identity.PluginCapability_Service_TYPE_BACKUP_SERVICE,

internal/cnpgi/operator/config/config.go

@@ -102,9 +102,7 @@ func (config *PluginConfiguration) GetReplicaSourceBarmanObjectKey() types.Names
 	}
 }
 
-// HasAnyBarmanObjectStore returns true if the configuration references at least
+// HasAnyBarmanObjectStore reports whether any barman object store is configured.
-// one barman object store, be it for backup/archiving, recovery, or as a
-// replica source.
 func (config *PluginConfiguration) HasAnyBarmanObjectStore() bool {
 	return len(config.BarmanObjectName) > 0 ||
 		len(config.RecoveryBarmanObjectName) > 0 ||

internal/cnpgi/operator/lifecycle.go

@@ -325,27 +325,24 @@ func (impl LifecycleImplementation) collectAdditionalInstanceArgs(
 // shouldInjectBarmanSidecar decides whether an instance pod needs the
 // plugin-barman-cloud sidecar.
 //
-// A cluster doing backup/archiving or serving as a replica source needs the
+// Backup/archiving and replica-source configs need it for as long as the
-// sidecar in every instance pod for as long as the cluster exists, so those
+// cluster exists, so those always inject it. A recovery-only cluster (only
-// two cases always inject it. A recovery-only cluster (only
+// RecoveryBarmanObjectName set, mirroring pluginConfiguration.Validate())
-// RecoveryBarmanObjectName set, mirroring what pluginConfiguration.Validate()
+// only needs it for the one-time bootstrap restore, so it's gated on
-// accepts) only ever needs the sidecar for its one-time bootstrap restore, so
+// cluster.Status.CurrentPrimary instead.
-// it's gated on cluster.Status.CurrentPrimary instead.
 //
-// CurrentPrimary is set by the instance manager itself, from inside the
+// CurrentPrimary is set by the instance manager itself, from inside the pod,
-// primary pod, only once it's up and has completed its own bootstrap (see
+// only once bootstrap completes (see instance_startup.go in cloudnative-pg).
-// instance_startup.go in cloudnative-pg) - unlike cluster.Status.Instances /
+// cluster.Status.Instances / IsInitialized() looks equivalent but flips as
-// IsInitialized(), which flips as soon as the instance's PVC exists, well
+// soon as the instance's PVC exists, before the pod is even created - using
-// before the pod is even created. Using IsInitialized() here would mean the
+// it here would mean the sidecar never reaches the pod that needs it.
-// sidecar is never added to the one pod that needs it to perform its restore.
 //
-// Once CurrentPrimary is set, this makes the operator's own drift-check
+// Once CurrentPrimary is set, the operator's drift-check
-// (checkPodSpecIsOutdated) see the running pod's spec as outdated and roll it
+// (checkPodSpecIsOutdated) sees the running pod's spec as outdated and rolls
-// out to drop the sidecar. That's deliberately accepted rather than
+// it out to drop the sidecar. Accepted deliberately: one deterministic
-// engineered around: it's one deterministic rollout using the same machinery
+// rollout via the same machinery used for any other pod-spec change
-// the operator already uses for every other pod-spec change (a switchover if
+// (switchover if a replica exists, in-place restart otherwise), not a new
-// a replica is available, an in-place restart otherwise), not a new or
+// risk.
-// fragile risk.
 func shouldInjectBarmanSidecar(
 	cluster *cnpgv1.Cluster,
 	pluginConfiguration *config.PluginConfiguration,

internal/cnpgi/operator/lifecycle_test.go

@@ -302,7 +302,6 @@ var _ = Describe("LifecycleImplementation", func() {
 			response, err := reconcileInstancePod(ctx, cluster, request, emptyConfig, sidecarConfiguration{})
 			Expect(err).NotTo(HaveOccurred())
 			Expect(response).NotTo(BeNil())
-			// An empty patch means the pod was left untouched: no sidecar injected.
 			Expect(response.JsonPatch).To(BeEmpty())
 		})