Rymote.Synapse.Core 1.0.0

Rymote.Synapse.Core

Strongly-typed in-process event bus for .NET 10. Part of Rymote.Synapse.

Rymote.Synapse.Core provides:

• An ISynapseBus you publish events to and subscribe handlers against.
• Three handler registration styles: delegate, IEventHandler<TPayload> classes resolved from DI, and methods marked [SynapseHandler] discovered by assembly scan.
• Per-message-type dispatch policy: Synchronous (handlers run on the publisher's task) or FireAndForget (handlers run on a per-subscription bounded channel reader).
• Per-subscription failure handling with retry / dead-letter / drop / rethrow decisions and pluggable backoff policies.
• Native .NET 10 observability via System.Diagnostics.ActivitySource (source Rymote.Synapse) and System.Diagnostics.Metrics.Meter (meter Rymote.Synapse).

AtLeastOnce dispatch requires Rymote.Synapse.Persistence.* (forthcoming). Clustered delivery requires Rymote.Synapse.Net and Rymote.Synapse.Cluster (forthcoming).

Quickstart

ServiceCollection services = new();
services.AddLogging();
services.AddScoped<OrderPlacedHandler>();

services.AddSynapse()
    .UseMessagePackSerialization()
    .ConfigureMessageType<OrderPlaced>(options => options.Dispatch = new DispatchPolicy.Synchronous())
    .AddHandler<OrderPlacedHandler>();

ServiceProvider provider = services.BuildServiceProvider();
provider.ActivateSynapse();

ISynapseBus bus = provider.GetRequiredService<ISynapseBus>();
await bus.PublishAsync(new OrderPlaced(orderId: Guid.NewGuid(), amount: 19.99m));

See the spec for the full architecture.

AtLeastOnce dispatch

AtLeastOnce requires a persistence provider — install Rymote.Synapse.Persistence.Memory (ephemeral) or Rymote.Synapse.Persistence.File (durable, forthcoming):

services.AddSynapse()
    .UseMessagePackSerialization()
    .UseMemoryPersistence()
    .ConfigureMessageType<PaymentCaptured>(typeOptions =>
        typeOptions.Dispatch = new DispatchPolicy.AtLeastOnce(
            MaxAttempts: 5,
            Backoff: BackoffPolicy.Exponential(TimeSpan.FromSeconds(1), TimeSpan.FromMinutes(1)),
            DeadLetter: new DeadLetterDestination.Channel("payments.dlq")));

Failed messages are dead-lettered as typed DeadLetterEnvelope<TPayload> events on the same bus:

bus.Subscribe<DeadLetterEnvelope<PaymentCaptured>>((envelope, context, ct) =>
{
    logger.LogWarning(
        "Payment {Id} dead-lettered after {Attempts} attempts: {Error}",
        envelope.Payload.Original.Payload.PaymentId,
        envelope.Payload.Attempts,
        envelope.Payload.LastExceptionMessage);
    return Task.CompletedTask;
});

DLQ subscriptions default to FireAndForget dispatch to prevent recursive dead-lettering.