public async Task HandleAsync(StartDelivery command)
{
if (command.Parcels is null)
{
throw new Exception("Parcels to be delivered were not specified.");
}
var parcels = new HashSet <Parcel>();
foreach (var parcelId in command.Parcels)
{
var parcel = await _parcelsRepository.GetAsync(parcelId);
if (parcel is null)
{
throw new Exception($"Parcel with id: {parcelId} to be delivered was not found.");
}
if (await _deliveriesRepository.IsParcelInDeliveryAsync(parcelId))
{
throw new Exception($"Parcel with id: {parcelId} is unavailable.");
}
parcels.Add(parcel);
}
if (!parcels.Any())
{
throw new Exception($"Delivery cannot be started without the parcels.");
}
_logger.LogInformation("Calculating the route...");
var route = await _routingServiceClient.GetAsync(parcels.Select(p => p.Address));
if (route is null)
{
throw new Exception("Route was not found.");
}
_logger.LogInformation("Route was calculated.");
await _deliveriesRepository.AddAsync(new Delivery(command.DeliveryId, parcels,
new Route(route.Addresses, route.TotalDistance)));
var eventsToPublish = parcels.Select(p => _messageBroker.PublishAsync(
new DeliveryStarted(command.DeliveryId, p.Id)));
await Task.WhenAll(eventsToPublish);
_logger.LogInformation($"Started a delivery with id: {command.DeliveryId}");
}
