Add option to ignore undated ("XXXX") and open-ended dated EDTF values in the search index

[seth-shaw-unlv]

The existing EDTF year index support currently builds an array of integer values to populate the index. By default this means that anything undated ("XXXX") results in the year "0", anything with an open beginning will go from 0 to the end year, and anything with an open end date will go from the beginning year until the current one. A site can set a default open and end year for the index but undated will still be year 0 which makes a terribly unwieldy slider facet widget that tries to accommodate over 2021 values....

We would like to filter out undated values and simply ignore the open date values. E.g. "../1984" or "1984/.." simply becomes "1984" in the index.

[kspurgin]

Ignoring XXXX for indexing seems fine to me.

Indexing ../1984 as 1984 also seems fine.

Seems like 1984/.. should index as 1984 to current year? Since generally something with a date like this is actively still being published

[seth-shaw-unlv]

Summary from the Tech Call: Yes make these configurable; also, make ignoring open beginning and open end separately configurable. Everyone seems fine with pushing the PHP requirements to 7.4 so we can use the Professional-Wiki EDTF library.

[seth-shaw-unlv]

Resolved by Islandora/controlled_access_terms#70