ELISE Workshop: Smart Data Loader and Templating for GeoServer (Part 2/3)
Channel: EU Location Interoperability & Innovation
Date: 22/02/2021

Under ELISE action, the API4INSPIRE study, which has been investigating new developments in geospatial standards and technologies, foremost the new OGC API – Features and SensorThings API standards, is coming to the conclusion. In autumn 2020 a workshop was held explaining what is Dynamic Data, and why is it a valuable enrichment of an SDI. In this workshop the speakers will explain:

How to efficiently deal with complex spatial data sources and make them useful in your daily work?

Exposing complex spatial data via web services is a challenging and often painful task, requiring an in-depth understanding of both the source data models and the target schema. This task becomes increasingly difficult as different data users require different profiles of the data encompassed within one source, for the implementation of different use cases serving different communities. Together with experienced data providers, we have developed an alternative approach to exposing complex data sources as required to support a wide range of use cases with minimal configuration effort. A modular approach allows for a separation of concerns, reducing the effort required for each step.

Our approach consists of the following two functionalities, now available as GeoServers plugins  for GeoServer:

Smart Data Loader: In contrast to the existing GeoServer App Schema configuration, where in-depth knowledge of the target data model is essential for configuration, under Smart Data Loader the structure of the data to be exposed is dependent purely on the underlying data source; a schema is generated mimicking the native database structure, and the data exposed in accordance. During configuration, starting from an initial table, the user can interactively specify to which depth the associated data will be nested, pruning those aspects that need not be externalized. The output of this step is made available via OGC API - Features, to be further refined via Feature Templating.

Feature Templating: Feature templating is where we align the output of the Smart Data Loader described above with the data models users are expecting. Here we’ve opted for a WYSIWYG approach, allowing the user to start with the final target, e.g., a simple JSON example, and then specify where the data content is to be taken from, e.g., an existing endpoint configured either via Smart Data Loader or also via the more traditional App Schema. With this templating approach, it becomes very simple to provide different profiles on one data source, each tailored to the needs of a specific community. At present templates can be specified in GeoJSON and JSON-LD; future work will extend this to XML (GML) and HTML.

In this webinar, Kathi Schleidt (INSPIRE Expert, co-chair of the OGC O&M SWG) from DataCove e.U. and Nuno Oliviera (Expert on OGC Services and their use within INSPIRE) from GeoSolutions, with support from Sylvain Grellet (INSPIRE Expert, co-chair of the OGC O&M SWG) from BRGM/ “INSIDE - environmental information systems research center" , will guide us through the steps described above based on real world examples progressing from simple to more complex use cases. The audience will see how we expose a data source in its native structure via Smart App Schema, then tailor it to specific usage areas and expose these via OGC API - Features.