[SLING-11504] BundleResource fallback sling:resourceType should be consistent with JcrNodeResource

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: Bundle Resource 2.3.4
• Assignee: Unassigned
• Reporter: Michal Cukierman
• Created: 29/Jul/22 14:53
• Updated: 29/Dec/22 16:44

Description

Background:

We work on Sling based CMS - https://www.websight.io . One of our current goals is to move /apps and /libs folders into bundle resources and get rid of JCR based sling scripting and configurations (JCR Installer). This is an alternative approach to CompositeNodeStore usage in order to support containerized environments, blue-green deployments, and separation of code, configuration, and data.

To achieve this, we move components (and dialogs) definitions from JCR into bundles and make them work with the same APIs (like Sling Resource Merger).

 

The problem:

JcrNodeResource and BundleResource use different mechanisms for calculating fallback sling:resourceType

• In JCR, Resource.getResourceType method is used to calculate resourceType if no explicit property is found in the repository. See https://github.com/apache/sling-org-apache-sling-jcr-resource/blob/72c105d67adc58ef1f4d43de78815fdcebb290b5/src/main/java/org/apache/sling/jcr/resource/internal/helper/jcr/JcrItemResource.java#L120]

• In Bundles, sling:resourceType is always set in the constructor and later overwritten by the JSON properties, if available. See: |https://github.com/apache/sling-org-apache-sling-bundleresource-impl/blob/master/src/main/java/org/apache/sling/bundleresource/impl/BundleResource.java#L91

It results in a different contract, in particular, it’s impossible to declare BundleResource with no sling:resorurceType property. The result can be observed in the following Groovy Script execution, where both nodes have no sling:resourceTypes declared:

Incompatible BundleResource and JCRNodeResource contracts requires workarounds in multiple APIs (our internal APIs / SlingResource Merger API) or to do workarounds at the data level.

 

Proposed solution:

I can reimplement BundleResource, so that sling:resourceType is calculated in the getter. This will result in a valid getResourceType() method contract with the possibility of having null sling:resourceType resource property.

Issue Links

• is related to: SLING-11506 Streamline and document resource (super) type merging
• links to: GitHub PR