Reintroduce and document the DockerImage kind for custom KIE server i… (

#179) (apache#4217)

* Reintroduce and document the DockerImage kind for custom KIE server image

* Peer review

doc-content/enterprise-only/openshift/operator-deploy-kieserver-proc.adoc

@@ -29,31 +29,23 @@ The custom hostname must be valid and resolvable.
 
 To change the custom hostname, you can modify the `routeHostname` property.
 ====
-. Optional: If you want to use a custom image for the {KIE_SERVER} deployment, complete one the following sets of additional steps:
-.. If you want to use a Docker image by specifying the image in the registry:
-... Set the custom registry in the *Installation* tab. If you do not set the custom registry, the installation uses the default Red Hat registry. For more information about setting the custom registry value, see xref:operator-deploy-basic-proc_{context}[].
-... In the *KIE Server* tab, set the following fields:
-**** *Image context*: The context of the image in the registry.
-**** *Image*: The name of the image.
-**** *Image tag*: The tag of the image. If you do not set this field, the installation uses the `latest` tag.
+. Optional: If you want to use a custom {KIE_SERVER} image, complete the following additional steps:
+.. Click *Set KIE Server image*.
+.. From the *Kind* list, select `ImageStreamTag` if you want to pull the image from an OpenShift image stream or select `DockerImage` if you want to pull the image from any Docker registry.
+.. Set the image name by completing one of the following steps:
+*** If you selected the `ImageStreamTag` kind, enter the image stream tag name of the image in the *Name* field, for example, `my-custom-is-tag:1.0`.
 +
-For example, if the full address of the image is `registry.example.com/mycontext/myserver:1.0-SNAPSHOT`, set the custom registry to `registry.example.com`, the *Image context* field to `mycontext`, the *Image* field to `myserver`, and the *Image tag* field to `1.0-SNAPSHOT`.
+If a corresponding image stream does not exist in your environment, the operator creates this image stream using the default Red Hat registry and tags. If you configured a custom registry in the *Installation* tab, the operator uses this registry for creating the image stream.
 +
-.. If you want to use an image from an existing OpenShift image stream:
-... Click *Set KIE Server image*.
-... Enter the name of the image stream tag in the *Name* field.
-... If the image stream is not in the `openshift` namespace, enter the namespace in the *Namespace* field.
+*** If you selected the `DockerImage` kind, enter the fully qualified image name for the image in the *Name* field, for example, `registry.io/test/testing:1.0`.
 +
-If the image stream tag is already configured in your OpenShift environment, the installation uses this tag. If the tag is not configured, the installation creates an image stream tag with the default image names and tags.
+You can configure an image from any registry that your environment can access.
 +
-[NOTE]
-====
-Do not change the *Kind* value to `DockerImage`. This option does not work in {PRODUCT} {ENTERPRISE_VERSION_LONG}.
-====
+.. If you want to use an image stream that is not in the `openshift` namespace, enter the namespace in the *Namespace* field.
 +
 For instructions about creating custom images, see xref:customimage-con_{context}[].
 +
-. If you want to configure an immutable {KIE_SERVER} using a Source to Image (S2I) build, complete the following additional steps:
+. Optional: If you want to configure an immutable {KIE_SERVER} using a Source to Image (S2I) build, complete the following additional steps:
 +
 [IMPORTANT]
 ====