PagePathHistory infinite loop

[AAD Web Team]

From time-to-time we end up with an infinite loop in the PagePathHistory module. The effect of this is that someone clicking on "What other URLs redirect to this page?" in the admin interface justs get the spinning icon. In the error log we get an entry about the allowed memory size being exhausted in PagePathHistory.module. Inside the module, the getVirtualHistory method is being endlessly called, alternating between two different page ids.

This seems to happen when we have two pages like this:

Page 1 URL: /one/two/three/
Old URL: /one/four/

Page 2 URL: /one/two/
Old URL: /one/four/five/

The only way to fix this seems to be to log into MySQL and delete rows from the page_path_history table.

Ideally we'd like ProcessWire to either stop users adding new redirect URLs that cause this problem, or to somehow handle and escape from the infinite loop that results. Is there a modification to the code that might achieve this?

[szabesz]

Hello,

Since this is a core issue, I recommend opening an issue for this at processwire-issues.

[szabesz]

Cross reference: https://github.com/processwire/processwire-issues/issues/1882