The ELisA Facility - RESTful API and Client Libraries

The ATLAS experiment at the LHC (CERN) comprises a large and geographically distributed community of about three thousand scientists from all over the world. A shift crew of about 10 people running the experiment 24/7 supervises the data taking. Information concerning the experiment operation and behavior has to be reported and shared with the whole community. To provide such functionality, a logbook facility, known as ELisA, has been developed to offer a user-friendly web interface to browse activity logs and an effective way for shifters and experts to report on system operations.Recently, the ELisA facility has been extended with a programmatic interface to the logbook functionality. Tools and services of the data acquisition infrastructure are the main users of this API. The ELisA RESTful API provides an HTTP-based interface to access, modify and create activity logs. The client libraries expose such interface to Python, Java and C++. In addition, a set of command line utilities has also been developed on top of the Python libraries. The description of the RESTful interface definition and implementation together with the technologies used, the client-server interaction and libraries are presented in the paper.