DeltaSignerInfoResponseListener listener) {
LocalWaveletContainer wavelet = loadLocalWavelet(waveletName, listener);
if (wavelet != null) {
HashedVersion endVersion = CoreWaveletOperationSerializer.deserialize(deltaEndVersion);
if (wavelet.isDeltaSigner(endVersion, signerId)) {
ProtocolSignerInfo signerInfo = certificateManager.retrieveSignerInfo(signerId);
if (signerInfo == null) {
// Oh no! We are supposed to store it, and we already know they did sign this delta.
LOG.severe("No stored signer info for valid getDeltaSignerInfo on " + waveletName);
listener.onFailure(FederationErrors.badRequest("Unknown signer info"));
} else {