Specifications and technologies

This is an overview of supported specifications and technologies. For constraints and limitations see the documentation of the ldproxy building blocks.

Web API Specifications

The following published standards and drafts of future standards for geospatial Web APIs or HTTP APIs are implemented in ldproxy:

The functionality implemented in lproxy will in general differ from the current draft specifications since the drafts are changing.

Additionally, several ldproxy extensions are supported for which no official drafts are available at this time.

ldproxy is certified as an OGC reference implementation for "OGC API - Features - Part 1: Core" and "OGC API - Features - Part 2: Coordinate Reference Systems by Reference"open in new window.

Certified OGC Compliant Logo


ldproxy supports the following formats that are supported by existing tools and libraries:

HTML can be annotated with schema.orgopen in new window markup (schema:Placeopen in new window, schema:Datasetopen in new window and schema:DataCatalogopen in new window).

Data Providers


All feature data in ldproxy is provided by feature providers, where each API has one provider. Two types of providers are supported:

  • PostgreSQL databases (version 9.6 or later) with PostGIS (version 2.4 or later)
    • All tables of a provider must be in one database and one schema. Each table, except intermediate tables, must have a unique identifier column (primary key or with unique index). It is recommended to use integers for the identifiers for performance reasons.
  • GeoPackage
  • OGC Web Feature Services (WFS)
    • The WFS should support the query parameters COUNT and STARTINDEX in the GetFeature operation.

2D Tiles

All tiles are provided by a tile provider.

Three types of tile providers are supported:

3D Tiles

All tiles are generated from a PostgreSQL feature provider with CityGML building features (LoD 1, LoD 2).