[SLING-11067] Extend URIProvider to not rely on exceptions if URIs can not be provided for a resource

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Component/s: API
• Assignee: Konrad Windszus
• Reporter: Konrad Windszus
• Created: 17/Jan/22 07:14
• Updated: 23/Nov/23 17:05
• Resolved: 23/Nov/23 17:05

Description

Currently URIProvider is not allowed to return null according to https://github.com/apache/sling-org-apache-sling-api/blob/333fa20f07a1d42897c9e0b6253bec5dcedb3e0b/src/main/java/org/apache/sling/api/resource/external/URIProvider.java#L48.
This forces every URIProvider to throw an exception for the (pretty common) case it cannot provide a URI for a resource.

As creating exceptions comes with quite some overhead, I would propose to enhance that interface.
As just allowing null return values would be backwards-incompatible I would propose to instead add a second method called Optional<URI> getOptionalUriForResource(Resource, Scope, Operation) with a default implementation which calls toUri(...) and properly catches and logs IllegalArgumentExceptions. At the same time I would deprecate the existing method toURI(...).

Compare with the discussion at https://lists.apache.org/thread/xfgmrxbv6n1k5y57v6kq9pxnkyr6hcyb

Issue Links

• relates to: SLING-7140 Support redirects to URLs provided by the underlying datastore.
• links to: GitHub PR
• links to: GitHub Pull Request #40