[SLING-5469] Resource Merger: Add some name prefixing mechanism for properties which are used by the resource merger itself

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Resource Merger 1.2.10
• Fix Version/s: Resource Merger 1.4.0
• Component/s: Extensions
• Assignee: Konrad Windszus
• Reporter: Konrad Windszus
• Created: 29/Jan/16 13:19
• Updated: 15/Mar/21 09:57
• Resolved: 08/Mar/21 18:54

Description

Currently within the resource merger it is not possible to

1. use the jcr:primaryType of the underlying resource, while the overlaid/overridden resource has a different jcr:primaryType.
   That is a problem because for a JCR the primaryType is mandatory for each node. Some node type definitions don't allow arbitrary property names like sling:hideResource. To be able to use those properties (which are only relevant up the point where the resource has been merged) you might need to use a more relaxed node type. Still you don't want that relaxed node type to appear as primaryType in the merged resource.
2. use the sling:resourceSuperType from the underlying resource, while the overridden resource has a different sling:resourceSuperType.
   This is kind of a edge case because sling:resourceSuperType would be used for two different things here:
   • for getting the underlying resource path for the OverridingResourcePicker
   • for the request resolution of the merged resource
     Sometime the value for each of the cases would be different.

Therefore I propose a general property name mangling mechanism which allows someone to use a prefix like sling-resource-merging_ for the properties, which are during the resource merging exposed as properties without the prefix. One example for case 1):

/apps/my/resource
- jcr:primaryType=nt:folder
- sling:resourceSuperType=apps/my/super/resource
- sling:hideProperties=customNodeTypePrefix:property1
- jcr:sling-resource-merging_primaryTypemyCustomNodeRestrictedNodeType

/apps/my/super/resource
- jcr:primaryType=myCustomNodeRestrictedNodeType
- customNodeTypePrefix:property1=test
- customNodeTypePrefix:property2=test

/mnt/override/apps/my/resource
- jcrPrimaryType=nt:unstructured (but should be myCustomNodeRestrictedNodeType)
- customNodeTypePrefix:property2=test

In this example it is impossible to let my merged resource have the nodeType myCustomNodeRestrictedNodeType (because that simply does not allow the property sling:hideProperties to be set in /apps/my/resource.