Exclude route from express middleware

Question

I have a node app sitting like a firewall/dispatcher in front of other micro services and it uses a middleware chain like below:

...
app.use app_lookup
app.u         


        

Answer 1

You can also skip route like this by putting a condition on req.originalUrl:

app.use(function (req, res, next) {

    if (req.originalUrl === '/api/login') {
    return next();
    } else {
         //DO SOMETHING
    }

Answer 2

There's a lot of good answers here. I needed a slightly different answer though.

I wanted to be able to exclude middleware from all HTTP PUT requests. So I created a more general version of the unless function that allows a predicate to be passed in:

function unless(pred, middleware) {
    return (req, res, next) => {
        if (pred(req)) {
            next(); // Skip this middleware.
        }
        else {
            middleware(req, res, next); // Allow this middleware.
        }
    }
}

Example usage:

app.use(unless(req => req.method === "PUT", bodyParser.json()));