Unable to update requestBody without using a deprecated record setter

[Profpatsch]

https://hackage.haskell.org/package/wai-3.2.2.1/docs/Network-Wai.html#v:requestBody is deprecated, thus there is no way of using it as a setter without using a deprecated symbol.

I used the following workaround module, I suggest we add this setter function:

{-# OPTIONS_GHC -Wno-deprecations #-}
{-# OPTIONS_GHC -Wno-name-shadowing #-}

module Wai where

import Data.ByteString (ByteString)
import Network.Wai (Request (requestBody))

-- | Workaround to un-deprecate the setter. see 'requestBody'.
setRequestBodyChunk :: IO ByteString -> Request -> Request
setRequestBodyChunk requestBody r =
  r {requestBody = requestBody}

[snoyberg]

PR welcome

[Vlix]

Would setRequestBodySource be a more appropriate name?

[kazu-yamamoto]

I guess that @Profpatsch chose setRequestBodyChunk as a partner of getRequestBodyChunk.

[Vlix]

Yeah, but it's not setting a chunk... so would it maybe be better to then just name it setRequestBody?

It's an easy addition, so I think I might pick this up. (maybe bundle it together with #710 )

EDIT: Just saw @dbeacham made a PR for this. #949

[kazu-yamamoto]

In my understanding, this IO ByteString can be called multiple times and returns "" finally.
I call it chunks.

[Vlix]

Hmmm, ok I can see your point. I guess the most important thing is to emphatically add documentation that the IO ByteString MUST provide data until the request body is completely produced, after which it MUST return "". So for example that someone shouldn't setRequestBodyChunk (pure bytestring) request, because that will cause loops or memory leaks if someone expects it to produce chunks. 🤔

Should we move this discussion over to #949 or should @dbeacham just keep an eye on this discussion? 😅

[dbeacham]

In my understanding, this IO ByteString can be called multiple times and returns "" finally.
I call it chunks.

I think setRequestBodyChunks is a reasonable name to complement getRequestBodyChunk given how they are both expected to behave.

I can also add some docs to mirror the information given in requestBody and getRequestBodyChunk that it should return "" once the body has been fully produced.

[Vlix]

Implemented in #949