A new remote web-based MDSplus data visualization system for EAST

Abstract

WebScope has been widely used in the Experimental Advanced Superconducting Tokamak (EAST) experiment for many years. The choice of the Java applet technology for its implementation has been successful, which allows for pulse data communication and instant feedback through various web browsers. Accessing MDSplus data with it however brings some inconvenience due to the majority of browsers have dropped support for Java plugin. Recently, a new web-based MDSplus data visualization system with the MVVM (Model–View–ViewModel) architecture has been developed. The flexibility brought by using JavaScript middle components in the architecture reduces the program coupling and improves the system availability. A further availability is proposed here, that is, using reverse proxy mechanism to publish the abstract interfaces provided by MDSplus separately from the visual resources, with the proxy to specify data request relationships. For incoming network traffic in the server pool, effective load balancing is ensured. The slice storage mechanism in MDSplus and thumbnail are now used for storing and reading long pulse data, and exporting data through proxy ports which ensures secure access to experimental data. Pulse access variables are also stored in cloud server for authorized users to share across devices. The system was successfully applied to EAST experiment and achieved good performance. The design details of the system are described in this paper.