Creating a expressjs middleware that accepts parameters

Question

Creating a expressjs middleware that accepts parameters

I am trying to create a middleware that can accept parameters. How can this be done?

example

app.get('/hasToBeAdmin', HasRole('Admin'), function(req,res){

})

HasRole = function(role, req, res, next){
   if(role != user.role){
      res.redirect('/NotInRole);
   }

   next();
}

node.js
express

Answer 1

function HasRole(role) {
  return function(req, res, next) {
    if (role !== req.user.role) res.redirect(...);
    else next();
  }
}

I also want to make sure that I don't make multiple copies of the same function:

function HasRole(role) {
  return HasRole[role] || (HasRole[role] = function(req, res, next) {
    if (role !== req.user.role) res.redirect(...);
    else next();
  })
}

Answer 2

app.get('/hasToBeAdmin', function(){
  hasRole(req, res, next, 'admin');
}, function(req,res){ // regular route });

var hasRole = function(req, res, next, role){
   if(role != user.role){
      res.redirect('/NotInRole);
   }

   next();
};