API request geo-validation excludes some valid regions

[melange396]

Validation of geographic values used in requests went into the API server code with #1095 . It uses our GeoMapper utility to determine if a geo value is valid but, unfortunately, this has some problems. geo=county:02261 exists in our data, but is not allowed by the request validator; the FIPS code previously existed but was split into two new regions in 2020 definitions. The GeoMapper uses 2020 definitions by default, but we also have 2019 definitions available. Thus, data for that region cannot be retrieved specifically (though it will be delivered along with other geos if using a wildcard ("geo=county:*") in the request).

Possibilities to address it include:

• using merged 2019 + 2020 definitions in the validator
• allowing any geo_values that are present in the database

Related:

• Produce helpful error message when requesting an unsupported or unavailable geo_type or time_type in Epidata$covidcast #640
• Error when API request is made for an invalid region? #1365
• User-supplied geo format should be checked and descriptive error returned #1625
• <Link to slack discussion>