Developing with a VH
By the developer’s point-of-view, a VH is a black box which takes care of mediating and harmonizing the information coming from multiple providers on behalf of the user.
Application communicates with the VH through an Internet endpoint
The communication between an application and the VH happens through one or more of the exposed VH endpoints.
Not all the developers are the same. They have different requirements and different expertise on the use of geospatial data. Some are geospatial data experts and they would like to port applications already working on existing data systems, others would like to integrate the VH geospatial data in their system, others would like to simply integrate geospatial information in their Web and mobile apps.
For that reason, there are three different ways to interact with the VH. They are not mutually exclusive, and the user can mix them if he/she needs to. However, each way targets a specific kind of developer to address specific requirements.
Standard geospatial interfaces: The VH exposes de-iure and de-facto standard interfaces for geospatial data discovery, access and visualization, such as OGC CSW, WFS, WCS, WMS. They allow to interact with the VH as if it is a single standard compliant data system. This interaction allows porting of existing applications which already uses standard interfaces and it is suitable for developers who are expert of geospatial interoperability who would like to have full control on the interaction with data sources.
RESTful API: The VH exposes the main functionalities for geospatial open data discovery and access through a RESTful API. It allows an easy interaction with the VH through any programming language which supports the HTTP protocol and the JSON message encoding.