Umbraco Engage UmbracoUrlAlias Fix - Fixes #19654

[cornehoskam]

This issue attempts to resolve issue #19654 by adding property awareness to the VariationContext, allowing packages like Umbraco Engage to blacklist certain propertyAliasses from being attempted to be segmented, like the umbracoUrlAlias property.

This code should be used as an example as it has no true backwards compatible as it stands right now, and has been tested with a local setup using Engage 13 and Umbraco 13, using a page with the 'umbracoUrlAlias' property configured. With the Umbraco CMS code that passes the propertyAlias to the variation context GetSegment method, and the code in Engage to blacklist segmenting of the 'umbracoUrlAlias' property, A/B Testing now properly works again on routes that would otherwise cause infinite loops due to routing issues and would fallback on not segmenting the entire page.

This has only been tested against Engage A/B Testing and Personalization, and not against the full scope of all other implications where the PublishedValue & NuCache GetValue may be used in the Core CMS.

[Copilot]

Pull Request Overview

This PR modifies the variation context system to include property alias awareness, enabling packages like Umbraco Engage to blacklist specific properties from segmentation. This fixes an issue where the umbracoUrlAlias property would cause infinite loops in A/B testing scenarios.

• Added property alias parameter to ContextualizeVariation methods across the variation context system
• Extended GetSegment method to accept an optional property alias parameter for property-specific segmentation logic
• Updated all calls to variation context methods to pass the property alias information

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
Property.cs	Updated all variation context calls to pass PropertyType.Alias parameter
VariationContextAccessorExtensions.cs	Modified extension methods to accept and forward property alias parameter
VariationContext.cs	Extended GetSegment method signature to include optional propertyAlias parameter
PublishedValueFallback.cs	Updated variation context calls to pass property alias from various fallback scenarios

[AndyButland]

This seems good to me @cornehoskam. I've just made some changes to resolve the backward compatibility issues.

Can you let me know if you think this needs any more? I.e. if you need to do any more testing to prepare the fix for Engage? Otherwise, we can merge this in for 13.11, and I'll look at cherry-picking it up to 16.

[cornehoskam]

Thank you for that @AndyButland!
I will get back to you early next week after some more testing with the new changes made!

[cornehoskam]

@AndyButland Done some more testing on the Engage side of things and all seems fine from my end!
The only thing worth noting is that this change is breaking for older version of Engage, as this change means that the new GetSegment method with the alias parameter needs to be overridden by Engage instead of the one without it, otherwise the default (empty string) segment will be returned in older versions of Engage.
Not a big issue if you ask me, as I can have the fix on the Engage side out within a couple days of the CMS being out as well, and I'll add a note to the changelog that with version 13.x of Umbraco, version 13.x of Engage is required for personalization and A/B testing to work.

[AndyButland]

OK, great, let's merge this in then and it'll be in 13.11 (not yet scheduled). I'll look at cherry-picking it up to 16.