expressJS: Limit acceptable content-types

Question

I have a expressJS API. In POST routes, I only accept two types of headers:

application/x-www-form-urlencoded

application/json

Is there a way that I can express to enforce to only accept the two headers and reject any other POST request and respond with some kind of 400 error?

Answer 1

You could use a simple middleware like this on a per-route basis or for all routes:

var RE_CONTYPE = /^application\/(?:x-www-form-urlencoded|json)(?:[\s;]|$)/i;
app.use(function(req, res, next) {
  if (req.method === 'POST' && !RE_CONTYPE.test(req.headers['content-type']))
    return res.send(415);
  next();
});