Organizations (names, or full objects with all_fields).
Full-text / faceted dataset search.
CKAN reads a repeated fq= key as a Python list and pastes it into the Solr
filter, which fails with HTTP 409. So a single filter is sent as fq, and
several are sent as CKAN's fq_list (each applied as its own Solr filter
query; all must match). fq_list is only used for two or more, because
CKAN splits a lone fq_list value into characters. Facet fields go out as
the JSON list CKAN expects in facet.field; it rejects facet_field with
HTTP 400.
Tags, optionally filtered by a query substring.
Optionalquery: string
Call any CKAN action by name and return its unwrapped
result. Throws a GovDataError if the envelope reportssuccess: false.