generateOpenRouterCodeChallenge function

String generateOpenRouterCodeChallenge(
  1. String verifier
)

Generates the S256 code challenge for a verifier.

Returns the base64url-encoded SHA-256 hash, without padding, as required by OpenRouter's PKCE docs.

Implementation

String generateOpenRouterCodeChallenge(String verifier) {
  final hash = sha256.convert(utf8.encode(verifier));
  return base64UrlEncode(hash.bytes).replaceAll('=', '');
}