`cabal upload` throwing curl errors

[hasufell]

Describe the bug

+ cabal upload --publish --publish -d dist-docs.nENRAe/file-io-0.1.3-docs.tar.gz
hackage.haskell.org username: maerwald
hackage.haskell.org password:
Uploading documentation dist-docs.nENRAe/file-io-0.1.3-docs.tar.gz...
Error: cabal: '/usr/bin/curl' exited with an error:
curl: (56) Illegal or missing hexadecimal sequence in chunked-encoding

Happens reproducibly.

To Reproduce

1. cabal v2-haddock --haddock-for-hackage --enable-doc --haddock-options=--quickjump
2. cabal upload --publish -d dist-newstyle/file-io-0.1.3-docs.tar.gz

Expected behavior

cabal upload should work or have actual error handling.

System information

• Operating system: Fedora 39
• cabal 3.12.1.0, ghc 9.8.2

[ulysses4ever]

Thanks for the report! Does it reproduce with 3.10?

[hasufell]

Thanks for the report! Does it reproduce with 3.10?

yes

[ulysses4ever]

Good. We should be catching more errors from auxiliary tools, for sure. But it's hard to do anytime meaningful if we don't understand the underlying issue.

Are you behind any kind of proxy? Cf. curl/curl#6760

If we find what curl command cabal tried to execute, we could experiment further. Perhaps, running cabal with -v (-v3?) would reveal the exact command.

If we know the command, running the same command with --trace log.txt as suggested in the ticket above could bring an insight...

[hasufell]

Are you behind any kind of proxy?

No.

[sgraf812]

I just hit the same error while trying to upload documentation for a candidate release of happy-lib here.

FWIW, for me the error was that I hadn't yet uploaded the regular sdist of the candidate package. This does not seem related; see below

[geekosaur]

Possibly relatedly, my Ubuntu system just received updates to both curl and wget. Since I don't do much uploading to Hackage (and in fact don't even have an account), I can't check to see if this introduced a new bug.

BTW, curl: (56) Illegal or missing hexadecimal sequence in chunked-encoding is not an error we can do anything about (wtf does it even mean? That's a curl internal burp), so I don't see the issue: we can't do anything other than report it to the user and bail.

[sgraf812]

I think in my case it would have helped to say "Hint: This curl error can occur when uploading haddocks for a package before uploading the package."

[geekosaur]

TBH I think the technically correct thing here is to see if the server outputs error text before it runs its side of the transaction — but I'm not sure that's practical unless it is changed to always output text of some kind (which will of course break every older version of cabal-install). So this strikes me as a poorly-designed Hackage protocol which can't sensibly be dealt with except by the kind of post facto heuristics you suggested, which will always be dubious.

[sgraf812]

I triggered the error again this morning. See haskell/hackage-server#1070. I think it would be great to sort this out; I don't think I made an error while typing in my password because it came from the clipboard (from my password manager), and that same password worked while uploading the code of the package candidate.