Archive WEB API: A web service for the experiment data archive of Wendelstein 7-X

Wendelstein 7-X was built for the research on steady state operation of stellarators. This sets high requirements on the control and data acquisition (CoDaC) system, with the archive database as one of its main components. W7-X Archive database is the storage of all operational and scientific data. It stores raw data as well as processed data and provides a single database for a wide range of components and data types. The Archive WEB API provides a unified access to the archive database by using web service technologies. The API is based on the REST architecture style, using HITP as the application protocol: the data is represented as a unified signal resource, which can be addressed via a URL. The users can read data in standard formats, like JSON or PNG. In the same way, the WEB API can be used to import new data to ArchiveDB. This paper describes the concepts of the WEB API and the experiences during the first operational phase of W7-X. (C) 2017 The Author(s). Published by Elsevier B.V.