Passing a `%JOSE.JWK{}` to `Signer.create()`

[acco]

Hey team,

I work with JOSE.JWK in their native struct in my codebase. Eg:

jwk = %JOSE.JWK{
  fields: %{},
  keys: :undefined,
  kty: {:jose_jwk_kty_okp_ed25519,
   <<22, 265, 220, 103, 320, 163, 18, 80, 12, 255, 235, 31, ...>>}
}

I want to be able to do something like this:

signer = Joken.Signer.create("Ed25519", jwk)

But this raises this error:

    The following arguments were given to JOSE.JWK.from_record/1:

        # 1
        {:error, {:missing_required_keys, ["keys", "kty"]}}

    Attempted function clauses (showing 2 out of 2):

        def from_record({:jose_jwk, keys, kty, fields})
        def from_record(list) when is_list(list)

So, my workaround is the following - which is fine, just not ideal:

signer = Joken.Signer.create("Ed25519", %{"pem" => JOSE.JWK.to_pem(pub_key) |> elem(1)}),

Any reason not to support passing in JWK's directly?

Thanks!

[victorolinasc]

Hi @acco ! No specific reason at all besides my short sight of things when I've implemented the Signer. A PR will certainly be welcomed. There is just the boring part of ensuring the signer can handle the desired algorithm. For instance: you pass a RSA key for an algorithm that expects an octet key or an elliptic curve key.