app.get('/auths', ensureAuthenticated, ensureCompleteProfile, function(req, res){
        withRoom(+req.param('id'), req.user.id, function(err, room) {
            if (!room) return res.render('error.jade', { error: "No room" });
            room.path = roomPath(room)
            mdb.con(function(err, con){
                if (err) return res.render('error.jade', { error: "No connection" });
                con.listRoomAuths(room.id, function(err, auths){
                    if (err) return res.render('error.jade', { error: err.toString() });
                    con.listOpenAccessRequests(room.id, function(err, requests){
                        if (err) return res.render('error.jade', { error: err.toString() });
                        con.listRecentUsers(room.id, 50, function(err, recentUsers){
                            if (err) return res.render('error.jade', { error: err.toString() });
                            var authorizedUsers = {}, unauthorizedUsers = [];
                            auths.forEach(function(a){
                                authorizedUsers[a.player] = true;
                                });
                            recentUsers.forEach(function(u){
                                if (!authorizedUsers[u.id]) unauthorizedUsers.push(u);
                                });
                            con.ok();
                            res.render('auths.jade', { room:room, auths:auths, requests:requests, unauthorizedUsers:unauthorizedUsers });
                        });
                    });
                });
            });
        });
});

// with promises
var Promise = require('bluebird');

var mdb = Promise.promisifyAll(require('./pgdb.js'));
var withRoomAsync = Promise.promisify(withRoom);

app.get('/auths', ensureAuthenticated, ensureCompleteProfile, function(req, res) {
    var con, room;
    withRoomAsync(+req.param('id'), req.user.id).then(function(roomArg) {
        room = roomArg;
        if (!room) throw NoRoomError();

        room.path = roomPath(room);
        return mdb.conAsync();
    }).then(function(conArg) {
        con = conArg;
        if (!con) throw NoConnectError();
        return con.listRoomAuthsAsync(room.id);
    }).then(function(auths) {
        return con.listOpenAccessRequestsAsync(room.id);
    }).then(function(requests) {
        return con.listRecentUsersAsync(room.id, 50);
    }).then(function(recentUsers) {
        var authorizedUsers = {};
        var unauthorizedUsers = [];

        auths.forEach(function(a) {
            authorizedUsers[a.player] = true;
        });
        recentUsers.forEach(function(u) {
            if (!authorizedUsers[u.id]) unauthorizedUsers.push(u);
        });
        con.ok();
        return res.render('auths.jade', {
            room: room,
            auths: auths,
            requests: requests,
            unauthorizedUsers: unauthorizedUsers
        });
    }).catch(NoRoomError, function(err) {
        // If you want to handle this error specifically
        // In this case it's not really needed because Error does the same,
        // but it's to give you an idea.
        return renderError(res, err.message);
    }).catch(Error, function(err) {
        // NoConnectError is caught here too
        return renderError(res, err.message);
    });
});

function renderError(res, message) {
    return res.render('error.jade', { error: message });
}

// Error subclasses
function NoRoomError() {
    this.name = 'NoRoomError';
    this.message = 'No room';
    this.stack = (new Error()).stack;
}
NoRoomError.prototype = new Error();

function NoConnectError() {
    this.name = 'NoConnectError';
    this.message = 'No connect';
    this.stack = (new Error()).stack;
}
NoConnectError.prototype = new Error();