register.js

function doesUserExist() { 
  var rowCount;
  pg.connect(conString, function (err, client, done) {
  client.query('SELECT user_id FROM clients.users where user_id=$1', [req.body.user], function(err, result) {        
  if (err) {
            console.log('error fetching client from pool', err);
        }
         else if (result.rowCount === 1) {
            return rowCount = 1;
         }
    })
  });
        return rowCount;
}