Selectors

To optimize response times and size, by default, the MVT and JSON API return a minimized response. This approach ensures peak performance and reduces tile payload sizes, which is critical for smooth map interactions. By using selectors, you can include the additional data points your application specifically requires.

Where to use

  • Station Features Only: Selectors are only applicable to station features (count: 1). They do not affect the properties of cluster features.
  • MVT and JSON endpoits only: Selectors can be used in both the MVT and JSON Tile services, but not in count endpoint.

Available selectors

Any field listed in the station properties for MVT and JSON tiles can be used as a selector in its respective service, with exception of the mandatory GeoJSON fields returned in JSON tile service.

Implementation

To request specific properties, append stationProperties[] query parameter to the tile request URL.

Behaviour Examples

When selectors are provided, the request returns only the specified fields.

GeoJSON

In the GeoJSON tile service, the mandatory GeoJSON fields (type and geometry) are always returned regardless of the selector choice.

MVT

In MVT Tile Service, only the parameters explicitly selected are returned as there is no mandatory fields.