According to tests, EVA JS Framework with WASM extension is about 20x times faster, than in regular mode.
- Obtain WASM extension from a EVA ICS representative.
- The extension requires EVA JS Framework version 0.3.25 or above.
- Unpack evajw-XXXX.tgz archive into the directory where EVA JS Framework is installed. E.g. if the framework is installed in /opt/eva/ui, the module should be placed in /opt/eva/ui/evajw.
- (Recommended). Make sure the system has wasm MIME type configured properly in /etc/mime.types. If corrections were made, restart SCADA Final Aggregator with eva sfa server restart command. If using front-end web server, e.g. NGINX, make sure its MIME is also configured (/etc/nginx/mime.types):
- Put the following code in your HMI, before starting the web-HMI application or EVA JS Framework:
$eva.wasm = true;
- The WASM module will be automatically loaded at framework start.
- To make sure the WASM module works fine, enable debug mode in EVA JS Framework:
$eva.debug = true;
- When debug mode is enabled, events processed by the WASM extension are prefixed with “W” (e.g. EVA::Wws state instead of a regular EVA::ws state).
- Also, the method get_mode returns current framework mode:
$eva.get_mode(); // "js" for regular, "wasm" for WASM extension
- The WASM extension is licensed for the specified customers’ domains and can not be used on others. If a user requires accessing web-HMI via IP address, it should be added in the license as well.
- The license is built-in into the copy of the WASM extension, owned by the customer.
- The license may have expiration time or be perpetual.
- To check the license expiration time manually, the following function can be used:
evajw.get_license_expiration(); // returns either null or the license // expiration timestamp
- The list of domains/IP addresses is encrypted and can not be read.