Unsupported property types "external identifier" and "edtf dates"

[SvenLieber]

Hello,

great plugin! We currently set up an internal Wikibase and this plugin really makes a difference in usability!

However, we've encountered a few issues and I am wondering if they are already on the agenda, as I am not sure how actively this plugin is maintained.

I think the issues are related to this issue #58
Namely the facetted search does not work for properties of type external identifier and for EDTF dates.

• For exernal identifiers (configured with type list) no search facet is shown in the UI, but if we manually include haswbfacet:P8 or -haswbfacet:P8 in the search query, it all of a sudden appears, but it does not work correctly.
• For EDTF dates (configured with type range) the search facet is shown, but does not filter correctly

We only have a few thousand test records and we checked that the index computing was finished successfully.

In our MetaBelgica use case, we build a cultural heritage authority file, so we basically have persons with different properties for external identifiers as well as birth/death dates (EDTF) and birth/death places (items), see image below.

For us, the search ideally should support scenarios such as "Persons without identifier property X and identifier property Y" or "Persons that have a value for identifier property X and identifier property Y". Thus in a way, this issue is also related to #257 and it would be great if besides list and range there would be another type for properties that do not show a list (because for these identifier properties a list in the facet UI would not make much sense as these are unique values which can not be aggregated meaningfully).

We also would love to contribute directly with a pull request, but unfortunately we aren't familiar with PHP nor the internal Wikibase framework.

As a workaround for the external identifier issue, we duplicated each identifier property and made a regular property for it, e.g. KBR ID and KBR URI. Then we can at least search and filter with the ID property that is not of type external identifier.