const ARROW = "https://unpkg.com/@jpmorganchase/perspective-examples/build/superstore.arrow";

window.addEventListener('WebComponentsReady', function() {

    // Fetch and load arrow data.
    var xhr = new XMLHttpRequest();
    xhr.open('GET', ARROW, true);
    xhr.responseType = "arraybuffer"
    xhr.onload = function() {

        // Get element from the DOM.
        var el = document.getElementsByTagName('perspective-viewer')[0];

        // Load the arrow response in the `<perspective-viewer>` DOM reference.
        el.load(xhr.response);

        // Toggle the config controls open.
        el.toggleConfig();
    }
    xhr.send(null);
});