[WICKET-6762] Support manual initialization of websocket connections

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.7.0
• Fix Version/s: 9.0.0-M5, 8.8.0
• Component/s: wicket-native-websocket
• Assignee: Martin Tzvetanov Grigorov
• Reporter: Thomas Heigl
• Created: 25/Mar/20 16:14
• Updated: 31/Mar/20 07:12
• Resolved: 31/Mar/20 07:12

Description

BaseWebSocketBehavior currently calls Wicket.WebSocket.createDefaultConnection() on DOM ready. I would like to be able to delay connection creation and trigger it myself.

Desktop users of our application tend to open quite a number of tabs from search result pages and other lists and Wicket creates a new websocket connection for all tabs opened in the background. 

I implemented a solution that uses the Page Visibility API to open and close websocket connections when a page becomes visible or hidden. Since I currently cannot disable the default connection, I'm closing the connection immediately:

if (document.hidden) {
  if (Wicket.WebSocket.INSTANCE) {
    Wicket.WebSocket.INSTANCE.close();
  }
}

var connectFunction = function () {
  if (document.hidden) {
    if (Wicket.WebSocket.INSTANCE) {
      Wicket.WebSocket.INSTANCE.close();
    }
  } else {
    if (!Wicket.WebSocket.INSTANCE) {
      Wicket.WebSocket.createDefaultConnection();
    }
  }
};
document.addEventListener('visibilitychange', connectFunction, false);

This works, but most browsers log an error like this:

Connection failed. WebSocket is closed before the connection is established.

A configuration option to disable automatic connection creation would solve this.

Issue Links

• links to: GitHub Pull Request #418