sign method
Signs the given data using the IAM Credentials API.
This method calls the IAM Credentials API signBlob endpoint to sign data as the impersonated service account.
Returns a record containing the signature as a base64-encoded String and the key ID used to sign the blob.
Throws ServerRequestFailedException if the signing operation fails.
See: https://cloud.google.com/iam/docs/reference/credentials/rest/v1/projects.serviceAccounts/signBlob
Implementation
Future<({String signedBlob, String keyId})> sign(List<int> data) => signBlob(
_sourceClient,
data,
serviceAccountEmail: targetServiceAccount,
universeDomain: _universeDomain,
);