RHIDP-4566: document how to manage PVCs in RHDH operator (redhat-developer#702)

* RHIDP-4566: document how to manage PVCs in RHDH operator

* Incorporated review suggestions

* Incorporate QE suggestion

Author: hmanwani-rh

modules/admin/proc-mount-directories-pvcs.adoc

@@ -0,0 +1,64 @@
+[id="proc-mount-directories-pvcs_{context}"]
+= Mounting directories from pre-created PVCs
+
+Starting from `v1alpha3`, you can mount directories from pre-created PersistentVolumeClaims (PVCs) using the `spec.application.extraFiles.pvcs` field.
+
+.Prerequisites
+* You have understanding of the mounting logic:
+** If `spec.application.extraFiles.pvcs[].mountPath` is defined, the PVC is mounted to the specified path.
+** If `spec.application.extraFiles.pvcs[].mountPath` is not defined, the PVC is mounted under the path specified in `spec.application.extraFiles.mountPath/`.
+** If `mountPath` is not defined, the PVC defaults to `/opt/app-root/src`, or you can use the {product-very-short} container's working directory if it is specified.
+
+.Procedure
+. Define the PVCs using the following YAML example:
++
+--
+.Example YAML file to define PVCs
+[source,yaml]
+----
+apiVersion: v1  
+kind: PersistentVolumeClaim  
+metadata:  
+  name: myclaim1  
+spec:  
+  accessModes:  
+    - ReadWriteOnce  
+  resources:  
+    requests:  
+      storage: 2Gi  
+---  
+apiVersion: v1  
+kind: PersistentVolumeClaim  
+metadata:  
+  name: myclaim2  
+spec:  
+  accessModes:  
+    - ReadWriteOnce  
+  resources:  
+    requests:  
+      storage: 2Gi 
+----
+--
+
+. Use the following configuration to specify how the PVCs are mounted in the container:
++
+--
+.Example configuration for mounting PVCs in a container
+[source,yaml]
+----
+spec:  
+  application:  
+    extraFiles:  
+      mountPath: /my/path  
+      pvcs:  
+        - name: myclaim1  
+        - name: myclaim2  
+          mountPath: /vol/my/claim
+----
+--
+
+.Verification
+Based on the configuration, the following directories are mounted in the container:
+
+* `/my/path/myclaim1`
+* `/vol/my/claim`

modules/admin/proc-rhdh-deployment-config.adoc

@@ -46,8 +46,10 @@ spec:
 ----
 
 `volumes`::
-Add an additional volume named `my-volume` and mount it under `/my/path` in the {product-short} application container.
 +
+--
+Add an additional volume named `my-volume` and mount it under `/my/path` in the {product-short} application container.
+
 .Example additional volume
 [source, yaml]
 ----
@@ -73,9 +75,9 @@ spec:
                       storageClassName: "special"
                 name: my-volume
 ----
-+
+
 Replace the default `dynamic-plugins-root` volume with a persistent volume claim (PVC) named `dynamic-plugins-root`. Note the `$patch: replace` directive, otherwise a new volume will be added.
-+
+
 .Example `dynamic-plugins-root` volume replacement
 [source, yaml]
 ----
@@ -95,6 +97,7 @@ spec:
                 persistentVolumeClaim:
                   claimName: dynamic-plugins-root
 ----
+--
 
 `cpu` request::
 

titles/admin-rhdh/title-admin.adoc

@@ -40,4 +40,5 @@ include::assemblies/assembly-admin-templates.adoc[leveloffset=+1]
 include::assemblies/assembly-techdocs-plugin.adoc[leveloffset=+1]
 
 // RHDH Operator deployment
-include::modules//admin/proc-rhdh-deployment-config.adoc[leveloffset=+1]
+include::modules/admin/proc-rhdh-deployment-config.adoc[leveloffset=+1]
+include::modules/admin/proc-mount-directories-pvcs.adoc[leveloffset=+2]