UI basics

HMI applications are served by SCADA Final Aggregator from EVA_DIR/ui directory and available by default at:


Typically, EVA ICS UI applications are completely written in JavaScript. The file, called “ui/index.html” (or “ui/index.j2”) should be the application entry point.

The applications are usually coded in HTML+JavaScript. The UI applications should use SFA API methods to authenticate, obtain data and execute various actions.


EVA ICS provides the following tools to simplify UI development:

  • EVA JS Framework - provides high-level JavaScript API with various typical HMI features, such as authentication, data synchronization, events, actions etc.

  • Serving structured data in convenient ways.

  • SFA Templates - server-side templates for HTML, JS and other text files.

  • SFA PVT - a special API to keep sensitive information securely and let it be accessible only to authenticated users.

  • HMI file uploads - file upload API.

  • API session tokens - use session-bound tokens to authenticate API calls

  • Ready-to-use applications for Mobile clients.

Custom error pages

HTTP error responses (400, 403, 404, 405, 409 and 500) can be customized with custom error pages. To customize an error response, create file EVA_DIR/ui/errors/<code>.html, e.g. EVA_DIR/ui/errors/404.html for HTTP Error 404 (Not Found).

Custom error pages can have .j2 extensions as well. In this case, they are processed as SFA Templates.

UI Favicon

If there is no way to define icon path with “link” HTML tag, put a file named “favicon.ico” in EVA_DIR/ui/ directory to override the default favicon.