tl;dr: mockup bug hinders related items widget in subsites (non-site-navroot).
Throwing this mockup bug / issue link over here to see if anyone has any ideas on normalizing and/or providing both site-root and nav-root path, such that non-site rootPath can actually work:
I spent at least a few debugging hours looking at this, but so far have only concluded that the pattern options need to support, and send something new:
- There is no way to infer site path from the page?
- There is no way to take context path (or basePath) and non-site rootPath and determine what the path to the common site-root is.
- I sense we need to add a sitePath option, in addition to rootPath and basePath.
- This is complicated by accidental lack of support for (computed) navigation root now in plone.app.widgets.utils.get_relateditems_options (used to work, does not now, requires integrator subclass the widget to do more work).
- context path is always preferred to the navigation root path, which is generally ignored.
The consequence of all these things: there is currently no apparent way to jail related items inside a subsite.
I would like to see this fixed before Plone 5.1 release (see also), but want to see if there is any input that should guide any attempt I make to fix it (in plone.app.widgets, mockup, and (possibly) in plone.app.z3cform).
If you have ideas, please feel free to comment here or on the GitHub issue.