Scorpion is a system developed to monitor KPIs for services of the NFDi4Biodiversity Service Catalog. In our context, KPIs are mostly focussed on usage of a service (e.g. Number of Unique Users). The KPI measurements are submitted in a push approach, so that every service provider is responsible for submitting their KPI measurements on a monthly basis to Scorpion. The system itself is structured in several layers:

• The storage layer contains three databases. The first database is a simple SQLite3 instance used to keep track of registered users and their roles. Second, a Neo4j instance is hosted to store the KPI profiles of all services. Lastly, an InfluxDB instance is used to store the KPI measurements.
• The API layer implements a REST API that is partially made available to external users. Besides that, it is used to facilitate the communication between the back- and front-end.
• The Graphical User Interface offers a submission form for monthly KPI measurements of a service, a basic visualization of the stored results and an administration view.

Scorpion provides access through its User Interface to all necessary features to submit KPI measurements for a particular service. Upon service registration through the system administration, users can submit measurements on a monthly basis. Features available are:

• KPI Submission Form
• Home View with
  • KPI Plot
  • KPI Measurement Table
  • Overview of all monitored services

As Scorpion is in a closed beta phase, a comprehensive documentation can only be provided on request in form of a hands-on session.

Scorpion has an administration view, which is only available to administrators. This view can be used to add new entities (e.g. service, KPI, category) to the system.