protected void When <T>(
Func <T, IDictionary <string, string>, string> getAggregateId,
Func <TAggregate, T, IDictionary <string, string>, CancellationToken, Task> act,
bool throwIfNotFound = true) where T : IMessage
{
_handlers.Add(typeof(T), async(message, headers, ct) =>
{
WrongExpectedStreamVersionException concurrencyException;
do
{
try
{
var aggregateId = getAggregateId((T)message, headers);
var aggregate = aggregateId == null
? new TAggregate()
: await _repository
.GetById <TAggregate>(aggregateId, ct)
.ConfigureAwait(false);
if (throwIfNotFound && string.IsNullOrWhiteSpace(aggregate.Id))
{
throw new InvalidOperationException($"{typeof(TAggregate).Name} {aggregateId} not found!");
}
await act(aggregate, (T)message, headers, ct)
.ConfigureAwait(false);
await _repository
.Save(aggregate, headers, ct)
.ConfigureAwait(false);
concurrencyException = null;
}
catch (WrongExpectedStreamVersionException ex)
{
concurrencyException = ex;
}
} while(concurrencyException != null);
});
}
public static Task <TAggregate> GetById <TAggregate>(this AggregateRepository repository, string id, CancellationToken cancellationToken = default(CancellationToken))
where TAggregate : IAggregateRoot, new() => repository.GetById <TAggregate>(id, int.MaxValue, cancellationToken);
