docs: def index(self, datastore_id=None):
          """ GET /datastores/{datastore_id}/datasources: Get all
              datasources within a given datastore."""
          datastore = self._get_datastore_by_id(datastore_id)
          if datastore is None:
              abort(404)
          discovery_result = discover_datasources(datastore.ogrstring)
          for datasource in discovery_result:
              datasource['href'] = h.url_for(controller="datasources", action="show", datastore_id=datastore_id, datasource_id=datasource['id'])
          # prevent JSON Array Cross-site Exploits (XSRF/CSRF)
          return {'datasources': discovery_result}