Grouping

The grouping end points are available for every aggregation resource (count, length, perimeter, area). They are accessed through an additional /groupBy/(grouping-type) resource. Group types are boundary, key, tag and type.

Note

For /elements/(aggregation)/density the group types boundary, tag and type are available.

For POST requests the fields are given analogous to GET requests. When you just have a smaller set of spatial parameters, a GET request fits perfectly. POST mostly makes sense when you start to use GeoJSON as input geometries.

Boundary

Groups the result by the given boundaries that are defined through any of the boundary query parameters.

POST /elements/(aggregation)/groupBy/boundary

Parameters:

• aggregation – aggregation type, one of area, count, length, perimeter

Query Parameters:

• <params> – see query-parameters at /elements(aggregation) endpoint

Key

Groups the result by the given keys that are defined through the groupByKeys query parameter.

POST /elements/(aggregation)/groupBy/key

Parameters:

• aggregation – aggregation type, one of area, count, length, perimeter

Query Parameters:

• <params> – see query-parameters at /elements(aggregation) endpoint

• groupByKeys – OSM key(s) given as a list and combined with the ‘AND’ operator; default: empty;

Here you can find a groupByKey example.

Note

The groupByKeys query parameter is only available for the /groupBy/key endpoint.

Note

The /groupBy/key endpoint is not available for /elements/(aggregation)/density.

Tag

Groups the result by the given tags that are defined through the groupByKey and groupByValues query parameters.

POST /elements/(aggregation)/groupBy/tag

Parameters:

• aggregation – aggregation type, one of area, count, length, perimeter

Query Parameters:

• <params> – see query-parameters at /elements(aggregation) endpoint

• groupByKey – OSM key e.g.: ‘highway’; mandatory, no default value (only one groupByKey can be defined), non matching objects (if any) will be summarised in a ‘remainder’ category

• groupByValues – OSM value(s) for the specified key given as a list and combined with the ‘AND’ operator, default: no value

Here you can find a groupByTag example.

Note

The groupByKey and the groupByValues query parameters are only available for the /groupBy/tag endpoint.

Type

Groups the result by the given OSM, or simple feature types that are defined through the types parameter.

POST /elements/(aggregation)/groupBy/type

Parameters:

• aggregation – aggregation type, one of area, count, length, perimeter

Query Parameters:

• <params> – see query-parameters at /elements(aggregation) endpoint

Boundary and Tag

Groups the result by the given boundary and the tags.

POST /elements/(aggregation)/groupBy/boundary/groupBy/tag

Parameters:

• aggregation – aggregation type, one of area, count, length, perimeter

Query Parameters:

• <params> – see query-parameters at /elements(aggregation) endpoint

• groupByKey – OSM key(s) given as a list and combined with the ‘AND’ operator, e.g.: ‘highway’, ‘building’; (one groupByKey parameter must be defined)

• groupByValues – OSM value(s) given as a list and combined with the ‘AND’ operator, default: no value

Here you can find a groupByBoundaryGroupByTag example.