Configmap OCP docs

Signed-off-by: Andrea Cosentino <[email protected]>

ocp-configmaps.adoc

@@ -0,0 +1,58 @@
+== OCP Secrets Retrieval with Apache Camel Kubernetes Component
+
+In Camel we provide the secret function to retrieve configmap values from a configmap resource.
+
+The syntax is pretty simple:
+
+....
+configmap:name/key[:defaultValue]
+....
+
+It’s important to restrict the ability to read configmap with the least amount of permissions for your cluster. So the application should run with a role with only list/read configmaps permission.
+
+This could be done with the following command:
+
+....
+oc create clusterrole configmapreader --verb=get --verb=list --resource=configmap --namespace=<namespace>
+....
+
+The minimum permissions are list and get.
+
+Alternatively, you can create a yaml file with the following content:
+
+....
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: configmapreader
+rules:
+- apiGroups:
+  - ""
+  resources:
+  - configmaps
+  verbs:
+  - get
+  - list
+....
+
+And then run 
+
+....
+oc apply -f <file_name>
+....
+
+The application will have to run with that clusterrole.
+
+This will ensure the running application won’t be able to do more than list and get configmap.
+
+The same configuration could be seen on OCP by following the Camel on
+OCP Best Practices repository, in particular, the OCP Configmaps section. You
+can follow the example for both the runtimes supported by Red Hat Build
+of Apache Camel:
+
+https://github.com/jboss-fuse/apache-camel-on-ocp-best-practices/tree/main/examples/ocp/configmaps/camel-quarkus/retrieval[Camel-Quarkus
+- Camel on OCP Best practices - Camel Quarkus - Configmap Retrieval]
+
+https://github.com/jboss-fuse/apache-camel-on-ocp-best-practices/tree/main/examples/ocp/configmaps/camel-spring-boot/retrieval[Camel-Spring-Boot
+- Camel on OCP Best practices - Camel Spring Boot - Configmap Retrieval]
+