<!DOCTYPE html>
<html>
<head>
<title>Eme createMediaKeys helper page</title>
<script>
// This script waits for a message then attempts to requestMediaKeySystemAccess
// then createMediaKeys. On success posts 'successCreatingMediaKeys' to the
// source of the message, on failure posts 'failureCreatingMediaKeys' and a
// description of the failure to the source of the message.

async function createMediaKeys() {
  const clearKeyOptions = [
    {
      initDataTypes: ["webm"],
      videoCapabilities: [{ contentType: 'video/webm; codecs="vp9"' }],
    },
  ];

  let access = await navigator.requestMediaKeySystemAccess(
    "org.w3.clearkey",
    clearKeyOptions
  );

  return access.createMediaKeys();
}
function setupMessageListener() {
  window.onmessage = async event => {
    // We don't bother checking the message data since it should always be
    // telling us to create media keys.
    try {
      let keys = await createMediaKeys();
      if (!keys) {
        event.source.postMessage("failureCreatingMediaKeys no keys", "*");
        return;
      }
      event.source.postMessage("successCreatingMediaKeys", "*");
    } catch (e) {
      event.source.postMessage(`failureCreatingMediaKeys ${e}`, "*");
    }
  };
}
window.onload = setupMessageListener;
</script>
</head>
<body>
</body>
</html>
