private async Task <(DataDeliveryReceipt, RequestReceiptStatus)> TryHandleDeliveryReceipt(IDepositNodesHandler deposit, Address consumer, ProviderSession session, DataDeliveryReceiptRequest request, INdmProviderPeer peer, bool isRetry = false) { while (true) { Keccak depositId = session.DepositId; DataDeliveryReceipt receipt = await peer.SendRequestDataDeliveryReceiptAsync(request, CancellationToken.None); if (_logger.IsInfo) { _logger.Info($"Received a delivery receipt for deposit: '{depositId}' from node: '{peer.NodeId}', status code: '{receipt.StatusCode}'."); } if (isRetry && receipt.StatusCode != StatusCodes.Ok) { if (_logger.IsWarn) { _logger.Warn($"Request receipt retry failed for: '{depositId}' from node: '{peer.NodeId}', status code: '{receipt.StatusCode}'."); } return(receipt, RequestReceiptStatus.Invalid); } switch (receipt.StatusCode) { case StatusCodes.Ok: if (await _receiptProcessor.TryProcessAsync(session, consumer, peer, request, receipt)) { return(receipt, RequestReceiptStatus.Ok); } return(receipt, RequestReceiptStatus.Invalid); case StatusCodes.InvalidReceiptRequestRange: { if (_logger.IsInfo) { _logger.Info($"Consumer for deposit: '{depositId}' from node: '{peer.NodeId}' claims {receipt.ConsumedUnits} consumed and {receipt.UnpaidUnits} unpaid units."); } UnitsRange range = request.UnitsRange; uint requestedUnits = range.To - range.From + 1; if (requestedUnits <= receipt.UnpaidUnits) { if (_logger.IsWarn) { _logger.Warn($"Consumer for deposit: '{depositId}' from node: '{peer.NodeId}' claimed an invalid range (while it was actually valid)."); } break; } uint graceUnits = requestedUnits - receipt.UnpaidUnits; uint totalGraceUnits = graceUnits + deposit.GraceUnits; bool hasReachedThreshold = await _receiptsPolicies.CanClaimPayment(totalGraceUnits, deposit.UnitPrice); if (hasReachedThreshold) { peer.SendGraceUnitsExceeded(depositId, deposit.ConsumedUnits, totalGraceUnits); if (_logger.IsWarn) { _logger.Warn($"Consumer for deposit: '{depositId}' from node: '{peer.NodeId}' claimed too many unpaid units, grace units exceeded ({totalGraceUnits})."); } return(receipt, RequestReceiptStatus.GraceUnitsExceeded); } if (_logger.IsInfo) { _logger.Info($"Unpaid units difference is: {graceUnits} ({requestedUnits} - {receipt.UnpaidUnits}). Lowering units amount for deposit: '{depositId}'."); } deposit.SubtractUnpaidUnits(graceUnits); deposit.SubtractUnmergedUnits(graceUnits); deposit.SubtractUnclaimedUnits(graceUnits); deposit.AddGraceUnits(graceUnits); session.SubtractUnpaidUnits(graceUnits); session.AddGraceUnits(graceUnits); if (range.To < graceUnits) { peer.SendGraceUnitsExceeded(depositId, deposit.ConsumedUnits, totalGraceUnits); if (_logger.IsWarn) { _logger.Warn($"Cannot request a receipt for deposit: '{depositId}' - grace units amount is greater than the receipt range ({graceUnits} > {range.To})."); } return(receipt, RequestReceiptStatus.GraceUnitsExceeded); } uint updatedRangeTo = range.To - graceUnits; if (range.From > updatedRangeTo) { if (_logger.IsWarn) { _logger.Warn($"Invalid updated range [{range.From}, {updatedRangeTo}] for: '{depositId}' - receipt request will not be send."); } return(receipt, RequestReceiptStatus.Invalid); } if (_logger.IsInfo) { _logger.Info($"Grace units for deposit: '{depositId}' is: {deposit.GraceUnits} (added {graceUnits})."); } UnitsRange updatedRange = new UnitsRange(range.From, updatedRangeTo); if (_logger.IsInfo) { _logger.Info($"Updated range for deposit: '{depositId}' [{updatedRange.From}, {updatedRange.To}]. Requesting receipt once again."); } request = request.WithRange(updatedRange, deposit.GetNextReceiptRequestNumber()); isRetry = true; continue; } case StatusCodes.InvalidReceiptAddress: { break; } case StatusCodes.Error: { break; } } return(receipt, RequestReceiptStatus.Invalid); } }