X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/1787892d32351988231a60b71900c6a623609c54..3cc3e3b2e319c9db92da2efdefec2672780c5df9:/docs/api/Reverse.md?ds=sidebyside diff --git a/docs/api/Reverse.md b/docs/api/Reverse.md index 999827a1..ef211b5a 100644 --- a/docs/api/Reverse.md +++ b/docs/api/Reverse.md @@ -1,70 +1,217 @@ -## Reverse Geocoding +# Reverse Geocoding -Reverse geocoding generates an address from a latitude and longitude. The optional `zoom` parameter specifies the level of detail required in terms of something suitable for a Leaflet.js/OpenLayers/etc. zoom level. +Reverse geocoding generates an address from a coordinate given as +latitude and longitude. + +## How it works + +The reverse geocoding API does not exactly compute the address for the +coordinate it receives. It works by finding the closest suitable OSM object +and returning its address information. This may occasionally lead to +unexpected results. + +First of all, Nominatim only includes OSM objects in +its index that are suitable for searching. Small, unnamed paths for example +are missing from the database and can therefore not be used for reverse +geocoding either. + +The other issue to be aware of is that the closest OSM object may not always +have a similar enough address to the coordinate you were requesting. For +example, in dense city areas it may belong to a completely different street. + +## Endpoint + +The main format of the reverse API is -### Parameters ``` -https://nominatim.openstreetmap.org/reverse? +https://nominatim.openstreetmap.org/reverse?lat=&lon=& ``` -* `format=[xml|json|jsonv2]` +where `lat` and `lon` are latitude and longitude of a coordinate in WGS84 +projection. The API returns exactly one result or an error when the coordinate +is in an area with no OSM data coverage. + + +!!! danger "Deprecation warning" + The reverse API used to allow address lookup for a single OSM object by + its OSM id for `[PHP-only]`. The use is considered deprecated. + Use the [Address Lookup API](Lookup.md) instead. + +!!! danger "Deprecation warning" + The API can also be used with the URL + `https://nominatim.openstreetmap.org/reverse.php`. This is now deprecated + and will be removed in future versions. + + +## Parameters + +This section lists additional parameters to further influence the output. + +### Output format + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| format | one of: `xml`, `json`, `jsonv2`, `geojson`, `geocodejson` | `xml` | + +See [Place Output Formats](Output.md) for details on each format. + + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| json_callback | function name | _unset_ | + +When given, then JSON output will be wrapped in a callback function with +the given name. See [JSONP](https://en.wikipedia.org/wiki/JSONP) for more +information. + +Only has an effect for JSON output formats. + + +### Output details + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| addressdetails | 0 or 1 | 1 | + +When set to 1, include a breakdown of the address into elements. +The exact content of the address breakdown depends on the output format. + +!!! tip + If you are interested in a stable classification of address categories + (suburb, city, state, etc), have a look at the `geocodejson` format. + All other formats return classifications according to OSM tagging. + There is a much larger set of categories and they are not always consistent, + which makes them very hard to work with. + + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| extratags | 0 or 1 | 0 | + +When set to 1, the response include any additional information in the result +that is available in the database, e.g. wikipedia link, opening hours. + + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| namedetails | 0 or 1 | 0 | + +When set to 1, include a full list of names for the result. These may include +language variants, older names, references and brand. - * Output format. - * `jsonv2` adds the next fields to response: - * `place_rank` - * `category` - * `type` - * `importance` - * `addresstype` -* `json_callback=` +### Language of results - * Wrap json output in a callback function (JSONP) i.e. `()` +| Parameter | Value | Default | +|-----------| ----- | ------- | +| accept-language | browser language string | content of "Accept-Language" HTTP header | -* `accept-language=` +Preferred language order for showing search results. This may either be +a simple comma-separated list of language codes or have the same format +as the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language). - * Preferred language order for showing search results, overrides the value specified in the "Accept-Language" HTTP header. - * Either uses standard rfc2616 accept-language string or a simple comma separated list of language codes. +!!! tip + First-time users of Nominatim tend to be confused that they get different + results when using Nominatim in the browser versus in a command-line tool + like wget or curl. The command-line tools + usually don't send any Accept-Language header, prompting Nominatim + to show results in the local language. Browsers on the contratry always + send the currently chosen browser language. -* `osm_type=[N|W|R]` `osm_id=` - * A specific osm node / way / relation to return an address for - * **Please use this in preference to lat/lon where possible** -* `lat=` `lon=` - * The location to generate an address for +### Result restriction -* `zoom=[0-18]` - * Level of detail required where `0` is country and `18` is house/building +| Parameter | Value | Default | +|-----------| ----- | ------- | +| zoom | 0-18 | 18 | -* `addressdetails=[0|1]` - * defaults to 0 - * Include a breakdown of the address into elements +Level of detail required for the address. This is a number that +corresponds roughly to the zoom level used in XYZ tile sources in frameworks +like Leaflet.js, Openlayers etc. +In terms of address details the zoom levels are as follows: -* `email=` + zoom | address detail + -----|--------------- + 3 | country + 5 | state + 8 | county + 10 | city + 12 | town / borough + 13 | village / suburb + 14 | neighbourhood + 15 | any settlement + 16 | major streets + 17 | major and minor streets + 18 | building - * If you are making large numbers of request please include a valid email address or alternatively include your email address as part of the User-Agent string. - * This information will be kept confidential and only used to contact you in the event of a problem, see [Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details. -* `polygon_geojson=1` - * Output geometry of results in geojson format. +| Parameter | Value | Default | +|-----------| ----- | ------- | +| layer | comma-separated list of: `address`, `poi`, `railway`, `natural`, `manmade` | _unset_ (no restriction) | -* `polygon_kml=1` - * Output geometry of results in kml format. +The layer filter allows to select places by themes. -* `polygon_svg=1` - * Output geometry of results in svg format. +The `address` layer contains all places that make up an address: +address points with house numbers, streets, inhabited places (suburbs, villages, +cities, states etc.) and administrative boundaries. -* `polygon_text=1` - * Output geometry of results as a WKT. +The `poi` layer selects all point of interest. This includes classic points +of interest like restaurants, shops, hotels but also less obvious features +like recycling bins, guideposts or benches. -* `extratags=1` - * Include additional information in the result if available, e.g. wikipedia link, opening hours. +The `railway` layer includes railway infrastructure like tracks. +Note that in Nominatim's standard configuration, only very few railway +features are imported into the database. -* `namedetails=1` - * Include a list of alternative names in the results. - * These may include language variants, references, operator and brand. +The `natural` layer collects feautures like rivers, lakes and mountains while +the `manmade` layer functions as a catch-all for features not covered by the +other layers. -### Example + +### Polygon output + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| polygon_geojson | 0 or 1 | 0 | +| polygon_kml | 0 or 1 | 0 | +| polygon_svg | 0 or 1 | 0 | +| polygon_text | 0 or 1 | 0 | + +Add the full geometry of the place to the result output. Output formats +in GeoJSON, KML, SVG or WKT are supported. Only one of these +options can be used at a time. + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| polygon_threshold | floating-point number | 0.0 | + +When one of the polygon_* outputs is chosen, return a simplified version +of the output geometry. The parameter describes the +tolerance in degrees with which the geometry may differ from the original +geometry. Topology is preserved in the geometry. + + +### Other + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| email | valid email address | _unset_ | + +If you are making large numbers of request please include an appropriate email +address to identify your requests. See Nominatim's +[Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details. + + +| Parameter | Value | Default | +|-----------| ----- | ------- | +| debug | 0 or 1 | 0 | + +Output assorted developer debug information. Data on internals of Nominatim's +"search loop" logic, and SQL queries. The output is HTML format. +This overrides the specified machine readable format. + + +## Examples * [https://nominatim.openstreetmap.org/reverse?format=xml&lat=52.5487429714954&lon=-1.81602098644987&zoom=18&addressdetails=1](https://nominatim.openstreetmap.org/reverse?format=xml&lat=52.5487429714954&lon=-1.81602098644987&zoom=18&addressdetails=1) @@ -83,7 +230,7 @@ https://nominatim.openstreetmap.org/reverse? B72 United Kingdom gb - + ``` @@ -94,10 +241,10 @@ https://nominatim.openstreetmap.org/reverse? ```json { "place_id":"134140761", - "licence":"Data © OpenStreetMap contributors, ODbL 1.0. http:\/\/www.openstreetmap.org\/copyright", + "licence":"Data © OpenStreetMap contributors, ODbL 1.0. https:\/\/www.openstreetmap.org\/copyright", "osm_type":"way", "osm_id":"280940520", -"lat":"-34.4391708", + "lat":"-34.4391708", "lon":"-58.7064573", "place_rank":"26", "category":"highway", @@ -119,14 +266,102 @@ https://nominatim.openstreetmap.org/reverse? } ``` -### Hierarchy - -* Admin level => XML entity - * 2 => `` - * 4 => `` - * 5 => `` - * 6 - * 7 => `` - * 8 => `` - * 9 => `` - * 10 => `` +##### Example with `format=geojson` + +* [https://nominatim.openstreetmap.org/reverse?format=geojson&lat=44.50155&lon=11.33989](https://nominatim.openstreetmap.org/reverse?format=geojson&lat=44.50155&lon=11.33989) + +```json +{ + "type": "FeatureCollection", + "licence": "Data © OpenStreetMap contributors, ODbL 1.0. https://osm.org/copyright", + "features": [ + { + "type": "Feature", + "properties": { + "place_id": "18512203", + "osm_type": "node", + "osm_id": "1704756187", + "place_rank": "30", + "category": "place", + "type": "house", + "importance": "0", + "addresstype": "place", + "name": null, + "display_name": "71, Via Guglielmo Marconi, Saragozza-Porto, Bologna, BO, Emilia-Romagna, 40122, Italy", + "address": { + "house_number": "71", + "road": "Via Guglielmo Marconi", + "suburb": "Saragozza-Porto", + "city": "Bologna", + "county": "BO", + "state": "Emilia-Romagna", + "postcode": "40122", + "country": "Italy", + "country_code": "it" + } + }, + "bbox": [ + 11.3397676, + 44.5014307, + 11.3399676, + 44.5016307 + ], + "geometry": { + "type": "Point", + "coordinates": [ + 11.3398676, + 44.5015307 + ] + } + } + ] +} +``` + +##### Example with `format=geocodejson` + +[https://nominatim.openstreetmap.org/reverse?format=geocodejson&lat=60.2299&lon=11.1663](https://nominatim.openstreetmap.org/reverse?format=geocodejson&lat=60.2299&lon=11.1663) + +```json +{ + "type": "FeatureCollection", + "geocoding": { + "version": "0.1.0", + "attribution": "Data © OpenStreetMap contributors, ODbL 1.0. https://osm.org/copyright", + "licence": "ODbL", + "query": "60.229917843587,11.16630979382" + }, + "features": { + "type": "Feature", + "properties": { + "geocoding": { + "place_id": "42700574", + "osm_type": "node", + "osm_id": "3110596255", + "type": "house", + "accuracy": 0, + "label": "1, Løvenbergvegen, Mogreina, Ullensaker, Akershus, 2054, Norway", + "name": null, + "housenumber": "1", + "street": "Løvenbergvegen", + "postcode": "2054", + "county": "Akershus", + "country": "Norway", + "admin": { + "level7": "Ullensaker", + "level4": "Akershus", + "level2": "Norway" + } + } + }, + "geometry": { + "type": "Point", + "coordinates": [ + 11.1658572, + 60.2301296 + ] + } + } +} +``` +