Use specific middleware in Express for all paths except a specific one

I would add checkUser middleware to all my paths, except homepage.

app.get('/', routes.index);
app.get('/account', checkUser, routes.account);

or

app.all('*', checkUser);
    
function checkUser(req, res, next) {
  if ( req.path == '/') return next();

  //authenticate user
  next();
}

You could extend this to search for the req.path in an array of non-authenticated paths:

function checkUser(req, res, next) {
  const nonSecurePaths = ['/', '/about', '/contact'];
  if (nonSecurePaths.includes(req.path)) return next();

  //authenticate user
  next();
}

Instead of directly registering User.checkUser as middleware, register a new helper function, say checkUserFilter, that gets called on every URL, but passed execution to userFiled` only on given URLs. Example:

var checkUserFilter = function(req, res, next) {
    if(req._parsedUrl.pathname === '/') {
        next();
    } else {
        User.checkUser(req, res, next);
    }
}

app.use(checkUserFilter);

In theory, you could provide regexp paths to app.use. For instance something like:

app.use(/^\/.+$/, checkUser);

Tried it on express 3.0.0rc5, but it doesn't work.

Maybe we could open a new ticket and suggest this as a feature?

You can set the middleware on each route also.

// create application/x-www-form-urlencoded parser
var urlencodedParser = bodyParser.urlencoded({ extended: false })

// POST /login gets urlencoded bodies
app.post('/login', urlencodedParser, function (req, res) {
  if (!req.body) return res.sendStatus(400)
  res.send('welcome, ' + req.body.username)
})