I tried to implement Ueberauth from github, but whenever the callback phase should be done, I’m getting an error message. This is how it looks like in the shell (see below). While searching for a solution, I saw others having quite similar issues with this error message which apparently has something to do with hackney? I couldn’t solve the issue however. Thanks for any kind of help.
I had this issue on a nerves build, had accidentally compiled a few libraries on OTP20, had to revert back to OTP19 and never cleaned up the deps that had compiled on OTP20.
:unicode_util was added in OTP20, so you may have a version issue with where you are compiling and where you are running your code.
Running mix deps.clean --all might not be enough. Especially with rebar dependencies there is sometimes some metadata in the download folder remaining.
By actually pinning to an older version, you forced mix to delete the downloaded sources and then download again. Therefore rebars metadata was wiped as well.
If you now get back to current, it should work as well.
If you upgrade your erlang version, it is best do delete deps and run mix deps.get again.
Delete the folders deps and _build in your project root.
If that does not work, then there really is a bug that seems to make rebar unable to decide if unicode_util_compat is needed for idna or not.
But I just took a deeper look into the sources of unicode_util_compat. Its quite a bunch of NIFs, and the build instructions for windows are missing. So in fact, downgrading to an older version should help.