sign method
Create a signature of the body
with key
return the signature as bytes
Implementation
@override
Uint8List sign(JWTKey key, Uint8List body) {
assert(key is SecretKey, 'key must be a SecretKey');
final secretKey = key as SecretKey;
final hmac = Hmac(
_getHash(name),
secretKey.isBase64Encoded
? base64Decode(secretKey.key)
: utf8.encode(secretKey.key),
);
return Uint8List.fromList(hmac.convert(body).bytes);
}