Saga Capability Catalog

LiteBus saga support is an Extension tier feature. It adds correlated state persistence around inbox command dispatch through IProcessorEnvelopeHook and ISagaContext.

Saga registration is composed from the inbox axis. There is no public top-level AddSagaModule(...) API in v6. Register saga through builder.AddInbox(inbox => inbox.EnableSaga(...)) and select exactly one store in the saga callback.

Lifecycle

Accept correlated inbox command
  -> lease inbox envelope
  -> SagaProcessorHook.BeforeDispatchAsync (load state)
  -> SagaProcessorHook.PrepareDispatchScope (attach message scope)
  -> in-process command dispatch
  -> SagaInboxCommandScopePreHandler (nested scope re-attach)
  -> ICommandHandler<TCommand> uses ISagaContext
  -> SagaProcessorHook.AfterDispatchAsync (save or complete)
  -> inbox terminal status persistence

Package Map

Package	Role	Why it exists
`LiteBus.DurableMessaging.Abstractions`	Durable contracts	Hook contract (`IProcessorEnvelopeHook`, `IProcessorEnvelope`) shared by inbox and outbox processors
`LiteBus.Saga.Abstractions`	Durable contracts	Saga contracts (`ISagaStore`, `ISagaContext`, `SagaCorrelation`, query and purge filters)
`LiteBus.Saga`	Core implementation	Saga runtime, nested builder, and explicit in-memory storage module
`LiteBus.Saga.InboxIntegration`	Feature bridge	Inbox builder entry point (`EnableSaga`) and command pre-handler module
`LiteBus.Saga.Storage.PostgreSql`	Feature bridge	PostgreSQL `ISagaStore`, schema scripts, startup initializer

Typical Composition Recipe

services.AddLiteBus(builder =>
{
    builder.AddMessaging(_ => { });
    builder.AddInbox(inbox =>
    {
        inbox.Contracts.Register<AdvanceOrderSagaCommand>("orders.saga.advance");
        inbox.UseInProcessDispatch();
        inbox.EnableSaga(saga =>
        {
            saga.MapState<OrderSagaState>("orders.saga.advance");
            saga.UseInMemoryStorage();
        });
    });
});

Capability Pages

ID	Page
`saga.processor-envelope-hooks`	processor-envelope-hooks
`saga.processor-hook`	processor-hook
`saga.handler-context`	handler-context
`saga.state-registration`	state-registration
`saga.inbox-integration`	inbox-integration
`saga.inbox-command-scope`	inbox-command-scope
`saga.correlation-and-tenancy`	correlation-and-tenancy
`saga.store`	store
`saga.in-memory-store`	in-memory-store
`saga.postgresql-storage`	postgresql-storage
`saga.optimistic-concurrency`	optimistic-concurrency

Test Executor Summary

Test executor	Project and path	Coverage focus
Unit	`tests/LiteBus.Storage.UnitTests/Saga/`	Hook phases, same-correlation scope isolation, registry resolution, in-memory concurrency, query, purge, and schema bootstrap
Integration	`tests/LiteBus.Storage.IntegrationTests/PostgreSql/`	End-to-end inbox plus saga plus PostgreSQL, orchestration depth, compensation, optimistic concurrency, connection ownership
Composition smoke	`tests/LiteBus.Runtime.UnitTests/Runtime/Composition/`	v6 composition wiring (`EnableSaga`) and correlated state persistence

Key Gaps Documented

Gap	Status in v6
Outbox saga support	Not implemented
Single transaction for inbox terminal plus saga save	Not implemented
Built-in scheduler, timeout orchestration, compensation DSL	Not implemented
EF Core saga store adapter	Not implemented
Saga-specific metrics and activity source	Not implemented
Automatic correlation id generation	Not implemented
Saga metrics and tracing	Use inbox processor signals; no saga-specific instruments in v6