Ruby

Export a Public Key as a JWK

Demonstrates the Chilkat PublicKey.GetJwk method, which returns the public key as a compact JWK (JSON Web Key). It takes no arguments; binary values use Base64url without padding and the member order is stable across calls.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: JWK is the JSON key format used across modern web security — JWT, OAuth, OpenID Connect. Exporting a public key to JWK is exactly what you do to publish it in a JWK Set (a jwks_uri endpoint) so others can verify your signatures. The stable member order matters because it makes the output reproducible, which is important when the JWK feeds into a thumbprint.

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Ruby

require 'chilkat'

success = false

#  Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
#  JWK, and other supported representations.
pubKey = Chilkat::CkPublicKey.new()
success = pubKey.LoadFromFile("qa_data/public.pem")
if (success == false)
    print pubKey.lastErrorText() + "\n";
    exit
end

#  Export the public key as a compact JWK (JSON Web Key).  Binary values use Base64url without
#  padding, and the member order is stable across calls.
jwk = pubKey.getJwk()
if (pubKey.get_LastMethodSuccess() == false)
    print pubKey.lastErrorText() + "\n";
    exit
end

print jwk + "\n";