VideoJS + XHR mod : Adding XHR interceptor

example.html

<link media="all" rel="stylesheet" href="https://unpkg.com/video.js@7.1.0/dist/video-js.css">
<script src="https://unpkg.com/video.js@7.1.0/dist/video.js"></script>

<video-js id="player">
    <source src="//video/index.m3u8" type="application/x-mpegURL" />
</video-js>
<script>
    var player = videojs("player");
    var prefix = "key://";
    var urlTpl = "https://domain.com/path/{key}";
    // player.ready
    player.on("loadstart", function (e) {
        player.tech().hls.xhr.beforeRequest = function(options) {
            // required for detecting only the key requests
            if (!options.uri.startsWith(keyPrefix)) { return; }
            options.headers = options.headers || {};
            optopns.headers["Custom-Header"] = "value";
            options.uri = urlTpl.replace("{key}", options.uri.substring(keyPrefix.length));
        };
    });
</script>