public async Task OnEvent(IAggregateEvent ev, string queryId = null)
{
queryId = queryId ?? ev.AggregateId;
var query = await queryStore.Get(queryId);
var data = query.Data;
if (query.Version >= ev.SequenceId)
{
// event already applied
return;
}
int originalVersion = query.Version;
if (originalVersion < ev.SequenceId - 1)
{
// fastforward to the current event's version
query = await FastForward(query, ev.SequenceId);
}
else
{
// query is sync, just apply the event
query.Data = mutator.InvokeEventMutator(data, ev);
query.Version = ev.SequenceId;
query.DateUtc = DateTime.UtcNow;
}
await queryStore.Set(queryId, query, originalVersion);
}
