public static async Task <InMemoryProjectionWriter <TView> > BuildAsync(string subject, TView view, CancellationToken cancellationToken = default)
{
if (cancellationToken.IsCancellationRequested)
{
cancellationToken.ThrowIfCancellationRequested();
}
var writer = new InMemoryProjectionWriter <TView>();
await writer.LoadViewAsync(subject, view, cancellationToken);
return(writer);
}
public async Task <TView> ApplyAsync(TView view, IEvent @event, CancellationToken cancellationToken = default)
{
if (cancellationToken.IsCancellationRequested)
{
_logger.LogInformation($"{nameof(InMemoryProjector<TView>)}.{nameof(ApplyAsync)} was cancelled before execution");
cancellationToken.ThrowIfCancellationRequested();
}
var subject = Guid.NewGuid().ToString();
var writer = await InMemoryProjectionWriter <TView> .BuildAsync(subject, view, cancellationToken);
var manager = _projectionManagerFactory.Create(writer);
await manager.HandleAsync(@event, cancellationToken);
return(await writer.RetrieveAsync(subject, cancellationToken));
}
public async Task <TView> ProjectAsync(string subject, DateTimeOffset timestamp, CancellationToken cancellationToken = default)
{
if (cancellationToken.IsCancellationRequested)
{
_logger.LogInformation($"{nameof(InMemoryProjector<TView>)}.{nameof(ProjectAsync)} was cancelled before execution");
cancellationToken.ThrowIfCancellationRequested();
}
var events = await _eventStore.GetEventsAsync(StreamId.From(subject), timestamp, cancellationToken);
var writer = await InMemoryProjectionWriter <TView> .BuildAsync(cancellationToken);
var manager = _projectionManagerFactory.Create(writer);
foreach (var @event in events)
{
await manager.HandleAsync(@event.Payload, cancellationToken);
}
return(await writer.RetrieveAsync(subject, cancellationToken));
}