Missing exported function BuildAuthURLWithRedirect

[TheGreatAbyss]

Hello thank you for this Library!

I need to use this library with PingOne and with signed authentication requests. There is currently no exported function to build an Auth URL with the HTTP Redirect Binding.

The current function BuildAuthURL calls the function BuildAuthURLFromDocument which has this singular line of code:

return sp.buildAuthURLFromDocument(relayState, BindingHttpPost, doc)

Unless this is a bug and it's supposed to call BindingHttpRedirect, the library appears to be missing the exported function BuildAuthURLWithRedirect

I have a PR in my personal Git with the requested changes: https://github.com/TheGreatAbyss/gosaml2/pull/1/files

If you would grant me access to the repo I'd be happy to push a branch and open a MR.

Thank You
-- Eric

[landron]

Azure (Microsoft Entra ID) also needs this if "Verification certificates" is active: "AADSTS76022: Cannot verify the signature of received authentication request since there is no certificate for verification configured in the application."

This issue says that the equivalent of BuildAuthURL is missing:

buildAuthURLWithRedirect := func(sp *saml.SAMLServiceProvider, relayState string) (string, error) {
  doc, err := sp.BuildAuthRequestDocument()
  if err != nil {
    return "", err
  }
  return sp.BuildAuthURLRedirect(relayState, doc)
}

Because of using BindingHttpRedirect instead of BindingHttpPost, this function call will add SigAlg= and Signature= query parameters next to SAMLRequest=.
(Personally, I would have them added all the time).