I am developing an application using Scotty and of course WAI. I would like to be able to limit the size of requests, both for body length and for headers. How can I do that? Is it possible to do it using a plain WAI middleware ?
I don't know details of Scotty, but it's certainly possible to set up a WAI middleware that will look at the requestBodyLength and, if it's too large, return an appropriate 413 status code page. One thing you'd need to deal with is if the upload body is sent with chunked encoding, in which case no content-length is present. but that's uncommon. You have the option of either rejecting those requests, or adding code to wrap the request body and return an error if it turns out to be too large (that's what Yesod does).