def _object_to_json_dict(obj: Any) -> Union[bool, int, float, str, Dict[str, Any]]:
    """Convert an object to a dictionary suitable for the JSON output.
    """
    if isinstance(obj, Enum):
        # Properly serialize Enums (such as OpenSslVersionEnum)
        result = obj.name

    elif isinstance(obj, ObjectIdentifier):
        # Use dotted string representation for OIDs
        result = obj.dotted_string

    elif isinstance(obj, x509._Certificate):
        # Properly serialize certificates
        certificate = obj
        result = {  # type: ignore
            # Add general info
            'as_pem': obj.public_bytes(Encoding.PEM).decode('ascii'),
            'hpkp_pin': CertificateUtils.get_hpkp_pin(obj),

            # Add some of the fields of the cert
            'subject': CertificateUtils.get_name_as_text(certificate.subject),
            'issuer': CertificateUtils.get_name_as_text(certificate.issuer),
            'serialNumber': str(certificate.serial_number),
            'notBefore': certificate.not_valid_before.strftime("%Y-%m-%d %H:%M:%S"),
            'notAfter': certificate.not_valid_after.strftime("%Y-%m-%d %H:%M:%S"),
            'signatureAlgorithm': certificate.signature_hash_algorithm.name,
            'publicKey': {
                'algorithm': CertificateUtils.get_public_key_type(certificate)
            },
        }

        dns_alt_names = CertificateUtils.get_dns_subject_alternative_names(certificate)
        if dns_alt_names:
            result['subjectAlternativeName'] = {'DNS': dns_alt_names}  # type: ignore

        # Add some info about the public key
        public_key = certificate.public_key()
        if isinstance(public_key, EllipticCurvePublicKey):
            result['publicKey']['size'] = str(public_key.curve.key_size)  # type: ignore
            result['publicKey']['curve'] = public_key.curve.name  # type: ignore
        else:
            result['publicKey']['size'] = str(public_key.key_size)
            result['publicKey']['exponent'] = str(public_key.public_numbers().e)

    elif isinstance(obj, object):
        # Some objects (like str) don't have a __dict__
        if hasattr(obj, '__dict__'):
            result = {}
            for key, value in obj.__dict__.items():
                # Remove private attributes
                if key.startswith('_'):
                    continue

                result[key] = _object_to_json_dict(value)
        else:
            # Simple object like a bool
            result = obj

    else:
        raise TypeError('Unknown type: {}'.format(repr(obj)))

    return result
Convert an object to a dictionary suitable for the JSON output.