GIS Publisher Service

The GIS Publisher service manages geospatial data and metadata in a gCube based infrastructure. It relies on the gCube information system to gather information on which platforms are available in the current scope, balancing the load between the different platform instances. Its goal is to deal with the heterogeneous GIS platforms offering a common interface to other gCube services / application which need to publish geospatial data. Since each platform has a different approach on how to manage data, the GIS Publisher service is designed as a pluggable service, delegating to each plugin the platform specific interaction to third party software. Other than abstracting from specific GIS platform implementations, the GIS Publisher balances the load between the platform instances, and manages the replicas of the same services.

Overall Design

Applications which need to publish geospatial data can interact with the service via the [GIS Publisher CL]. A GISRequestConfiguration object is sent to the service, specifying :

• The GISData to publish
• The destination platform type
• Information to generate layers

The service enqueues every received request, assigning it a unique identifier. When a request is handled, the appropriate plugin is selected and invoked. At the end of the process a publish operation object is returned to the client, reporting information on :

• Published data references
• Published metadata
• Error messages (in case some of the operations fail)

Modules

The service is distributed as a set of maven artifacts:

• org.gcube.data.publishing.gis-publisher, parent for service and stubs implementation.
• org.gcube.data.publishing.gis-publisher-service, service implementation.
• org.gcube.data.publishing.gis-publisher-stubs, service stubs.
• org.gcube.data.publishing.gis-publisher-plugin-framework, library with common data model and plugin interfaces definition.
• org.gcube.data.publishgin.gis-publisher-client-library, client library to interact with the service.

GIS Publisher CL

Client library is developed on top of gCube CL Framework. It exposes synchronous and asynchronous methods to interact with the service.

Publising data

To publish data, callers need to specify two objects:

• GISRequestConfiguration object : among the other information, this object states
  • destination platform type (i.e GeoServer,THREDDS)
  • to generate styles definition : styles to generate prior layer generation
  • to generate layers definition : information to publish layers based on the passed data

• GISData object : the actual data to publish, it can be one of the following types
  • Streamed geospatial objects (see gCube Streams Library)
  • GISFile (i.e. CSquareCode CSV File, NetCDF etc.)