Geocoders

A geocoder turns a typed address or place name into a location. In GratisGIS a geocoder is an item of type Geocoding service, not an admin page. Anyone who can create items can make one, and sharing controls who can use it.

Make one

1. New item -> Geocoding service. Give it a title.
2. On the item page, pick the source: - Use your own data. Search a data layer, for example a parcels or address points layer. Pick the layer, then the fields to search and how much each one counts. The search index builds when you save. - Use an existing ArcGIS GeocodeServer. Paste the GeocodeServer URL, for example a statewide locator, and probe it. The portal sends queries to it for you.
3. Set the options: how many candidates to return (1 to 50), the minimum score (0 to 1), and for your own data, a spatial extent and a result label template.
4. Try addresses in Test geocoder before anyone relies on it.

Use it in a map

In the map editor, choose the geocoder for the map's search bar. The search bar then shows results from that geocoder alongside matches in the map's own layers.

Address search without a geocoder item

The map search bar also searches addresses through the portal's /api/geocode route, which uses the Nominatim instance the operator configured with NOMINATIM_URL. With none configured, it falls back to the public OpenStreetMap Nominatim service unless the operator set NOMINATIM_PUBLIC_FALLBACK=0. Those are server settings, not something you set in the portal. See infra/NOMINATIM.md for running your own.

Notes

• There is no built-in support for Photon, Pelias, Google or a custom HTTP geocoder, and no failover between geocoders.
• An external GeocodeServer sees every query sent to it. Check its terms and whether your addresses may leave your network.