This document covers the release 12.07 of the NodeSoftware.

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Introduction

About VAMDC

The Virtual Atomic and Molecular Data Center is a EU FP7 research infrastructure project and you can read all about it on http://vamdc.eu/

VAMDC nodes

A “node” within VAMDC is a data service that offers its data using the standards and protocols defined by the VAMDC. They are web services with a simple API, the specification of which can be found in the documentation for the VAMDC standards: http://vamdc.org/documents/standards/

The scope of this document is to serve as documentation for the reference implementation of such a service. The goal of this implementation is to serve as publishing tools for new data services, i.e. it is meant to be easily deployed at multiple nodes.

A versatile implementation of VAMDC standards

Principle design decisions that were made to arrive at this software package include

  • Open source. No software licences need to be bought and the used software can be adapted if needed.
  • The data must exist in a relational database. If this is not the case yet, a tool for creating it is provided.
  • Flexibility in the data structure. The service should be able to be plugged on top of existing databases and therefore needs to cope with almost arbitrary internal data formats.
  • Re-usable code. The implementation of the VAMDC standards and protocols themselves should not depend on the requirements of a specific node.

Since the last two points contradict each other in practice, there needs to be an intermediate layer of abstraction that hides the node-specific details like the database layout from the parts of code that are shared between nodes.

Our implementation of the VAMDC node software is therefore based on a framework called Django (which in turn is based on the programming language Python) that provides both the database abstraction layer and high level tools for implementing web services.

The ingredients for a VAMDC node based on this software package and its operation look schematically like this:

Structural layout of a VAMDC node