Sample code for 30+ languages & platforms
Unicode C++

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.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkPublicKeyW.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
    //  JWK, and other supported representations.
    CkPublicKeyW pubKey;
    success = pubKey.LoadFromFile(L"qa_data/public.pem");
    if (success == false) {
        wprintf(L"%s\n",pubKey.lastErrorText());
        return;
    }

    //  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.
    const wchar_t *jwk = pubKey.getJwk();
    if (pubKey.get_LastMethodSuccess() == false) {
        wprintf(L"%s\n",pubKey.lastErrorText());
        return;
    }

    wprintf(L"%s\n",jwk);
    }