Routing for 404, and Pending Sunset of XPath

[markadrake]

What type of issue is it? (Choose one - delete the others)

Missing documentation

What article/section is this about?

Custom Error Page
https://github.com/umbraco/UmbracoDocs/blob/main/13/umbraco-cms/tutorials/custom-error-page.md

Describe the issue

1. The GUID solution is the least optimal, and I would not consider it realistic. Even your documentation warns against this approach.
2. XPath seems to be not just the best solution but the only viable solution for ordinary circumstances. For instance, if you wish to serve 404 pages in a multi-tenant environment. This immediately solves the dilemma of localization. It's the only solution that works in production.
3. This page does not reference standard XPath placeholder variables. I also suspect the most common scenario would be to route to a specific content type dedicated to 404 pages under the current site root. If it weren't for the pending sunset of XPath, this documentation should be updated to include such a scenario.
4. It's crucial to note that throughout Umbraco's documentation, including this page, it's mentioned that "XPath is suboptimal and will be removed in a future version." This message should include more information, or at minimum a link to an article with more information, about what the replacement for XPath will be. This is a significant issue that needs to be addressed promptly.

[markadrake]

Please check this comment for a reference to $site, which doesn't seem to be documented anywhere.

In Umbraco 14's documentation, there is no page for "404" or "Error Routing" (yet).

There is no indication of what will replace XPath or if there is any feature parity here—specifically, variable placeholders that allow for dynamic queries based on the current or closest content.

[alina-tincas]

Hi @markadrake, thank you for bringing this to our attention!

On v13 and there is a warning that "The current implementation of XPath is suboptimal and will be removed entirely in a future version. It is currently obsolete and scheduled for removal in v14." so this means that in v14 documentation we will update this accordingly.

In v14 there is going to be a replacement for ContentXPath and the v14 documentation will be updated accordingly with the replacement at some point before the release in May. I will update this issue with the new replacement once I have it
confirmed with our CMS developers.

Regarding your comment related to umbraco/Umbraco-CMS#15582 (comment), we are currently awaiting for this to be thoroughly investigated by the CMS developers/community before making any updates to the documentation as perhaps it is only in some specific scenarios (such as upgrading from previous versions) that the ContentXPath path is not working accordingly.
You are also most welcome to contribute to our documentation if you have any suggestions to the documentation and we can take it from there.

[alina-tincas]

Hi @markadrake I have created a PR #6027 where I have:

• updated the warning note on v13 that there might be some issues after upgrading to v13 if Xpath was implemented before migration and what is the replacement for ContentXPath, which is IContentLastChanceFinder
• updated the 404 example so that instead of ContentXPath it uses IContentLastChanceFinder

As the PR is merged, you can view the updated article here: https://docs.umbraco.com/umbraco-cms/v/14.latest-beta/tutorials/custom-error-page#set-a-custom-404-page-using-icontentlastchancefinder

I will keep this issue open until the CMS issue is properly investigated so that others are aware there are some issues when migrating to v13 when using xpath and that the docs will be updated only when there is clear information on what scenario and what needs to be changed 💪

[alina-tincas]

Hi @markadrake this issue will be fixed in 13.4.0 of CMS: umbraco/Umbraco-CMS#15582 (comment) so am closing this one. Thank you again for bringing this to our attention 😊