Explicitly detect mimetype support using test sounds.

guacamole/src/main/webapp/scripts/interface.js

@@ -61,6 +61,9 @@ var GuacamoleUI = {
 
 };
 
+// Supported mimetypes
+GuacamoleUI.supportedAudio = {};
+
 // Constant UI initialization and behavior
 (function() {
 
@@ -484,6 +487,33 @@ var GuacamoleUI = {
         GuacamoleUI.eventTarget.style.top = window.pageYOffset + "px";
     });
 
+    function testAudio(url, mimetype) {
+
+        // If browser says we can't play it, don't try
+        var audio = new Audio();
+        if (!audio.canPlayType(mimetype))
+            return;
+
+        // Otherwise, test
+        audio.src = url;
+
+        // On error, explicitly unsupported
+        audio.addEventListener("error", function() {
+            GuacamoleUI.supportedAudio[mimetype] = false;
+        });
+
+        // On successful play, explicitly supported
+        audio.addEventListener("ended", function() {
+            GuacamoleUI.supportedAudio[mimetype] = true;
+        });
+
+        audio.play();
+
+    }
+
+    testAudio("sounds/silence.mp3", "audio/mpeg");
+    testAudio("sounds/silence.ogg", "audio/ogg");
+
 })();
 
 // Tie UI events / behavior to a specific Guacamole client