router.post('/api/users/authenticate', function(req, res, next) {
    var username = req.body.username;
    var password = req.body.password;

    console.log("post authentication request received.\n");

    console.log("username is: " + username + "\n");
    console.log("password is: " + password + "\n");

    var url = 'mongodb://localhost/admin';

    var authenticate = function(db, callback) {
        var cursor = db.collection('users').find({
          "username" : username,
          "password" : password}
        );

        var array = new Array();


        var isAuthenticated = false;

        cursor.each(function(err,doc)
        {

                if (err)
                {
                    console.log(err);

                }
                else
                {
                    console.log('Fetched:', doc);

                    isAuthenticated = true;

                    console.log("succesfully authenticated1. ");

                    console.log("isAuthenticated1 is: " + isAuthenticated + "\n");
                }
        });
        callback(isAuthenticated);
    };

    MongoClient.connect(url, function(err, db) {
        assert.equal(null, err);
        authenticate(db, function(isAuthenticated) {
            //res.writeHead(200, {"Content-Type": "text/plain"});

            console.log("callback ran <<<<<<<<<-----------");
            console.log("isAuthenticated3 is: " + isAuthenticated + "\n");

            if (isAuthenticated == true) {
                    res.json({authenticated: 'true'});
            } else {
                    res.json({authenticated: 'false'});
            }
            db.close();
        });
    });
});