app.get('/ui/ep/dir/list', ( a_req, a_resp ) => {

    // Aaron should do some work here to determine the collection type

    // if it is a mapped collection – might need if statement, need to check if we need to go through consent flow or not
    // if it is a mapped collection Collection UUID and Collection type need to be included in UserGetAccessTokenRequest message
    // If token is already stored and not expired needs to be returned here.
    // If token is expired need to indicate if token is valid
    sendMessage( "UserGetAccessTokenRequest", {}, a_req, a_resp, function( reply ) {

        const opts = {
            hostname: 'transfer.api.globusonline.org',
            method: 'GET',
            path: '/v0.10/operation/endpoint/' + encodeURIComponent(a_req.query.ep) + '/ls?path=' + encodeURIComponent(a_req.query.path) + '&show_hidden=' + a_req.query.hidden,
            rejectUnauthorized: true,
            headers:{
                Authorization: ' Bearer ' + reply.access
            }
        };

        const req = https.request( opts, (res) => {
            var data = '';

            res.on('data', (chunk) => {
                data += chunk;
            });
            res.on('end', () => {
                a_resp.json(JSON.parse(data));
            });
        });

        req.on('error', (e) => {
            a_resp.status( 500 );
            a_resp.send( "Globus endpoint directoy listing failed." );
        });

        req.end();
    });

});