Minor Description
1) Method should be abstract: https://javaserverfaces.github.io/docs/2.3/javadocs/javax/faces/application/ViewHandler.html#getWebsocketURL-javax.faces.context.FacesContext-java.lang.String-
2) public static final java.lang.String WEBSOCKET_PORT = "javax.faces.WEBSOCKET_PORT" -> This should not exist in the ViewHandler API according to the javadoc so moving it.
I believe we'll need a dev-discussion here as it looks like the spec specifies the following:
javax.faces.WEBSOCKET_ENDPOINT_PORT:
In case your server is configured to run a WebSocket container on a different TCP port than the HTTP
container, then you can use the optional javax.faces.WEBSOCKET_ENDPOINT_PORT integer context
parameter in web.xml to explicitly specify the port.
<context-param>
<param-name>javax.faces.WEBSOCKET_ENDPOINT_PORT</param-name>
<param-value>8000</param-value>
</context-param>
The following dev discussion outcome was to change the name of our parameter to match the spec: https://www.mail-archive.com/dev@myfaces.apache.org/msg68684.html