Stratara.Outbox.RabbitMQ 4.0.3

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dotnet add package Stratara.Outbox.RabbitMQ --version 4.0.3
                    
NuGet\Install-Package Stratara.Outbox.RabbitMQ -Version 4.0.3
                    
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="Stratara.Outbox.RabbitMQ" Version="4.0.3" />
                    
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageVersion Include="Stratara.Outbox.RabbitMQ" Version="4.0.3" />
                    
Directory.Packages.props
<PackageReference Include="Stratara.Outbox.RabbitMQ" />
                    
Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.
paket add Stratara.Outbox.RabbitMQ --version 4.0.3
                    
#r "nuget: Stratara.Outbox.RabbitMQ, 4.0.3"
                    
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
#:package Stratara.Outbox.RabbitMQ@4.0.3
                    
#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package.
#addin nuget:?package=Stratara.Outbox.RabbitMQ&version=4.0.3
                    
Install as a Cake Addin
#tool nuget:?package=Stratara.Outbox.RabbitMQ&version=4.0.3
                    
Install as a Cake Tool

Stratara.Outbox.RabbitMQ

Derived. The behaviour described here is specified under openspec/specs/. Those specifications are the source; this page explains and illustrates them.

License: MIT.

Outbox-pattern command + event dispatch for the Stratara event-sourced stack with a RabbitMQ message-bus implementation. Contains the write-side dispatchers, the outbox-retry worker, the read-side mediator command worker, the RabbitMQ bus, and the Redis-backed ProjectionReplayState that coordinates dispatch skip during projection replay. Azure Service Bus ships separately as Stratara.Outbox.AzureServiceBus.

What's in the box

Folder Contents
Outbox/ OutboxOptions, CommandOutboxDispatcher (write-side ICommand fan-out via IMessageBus, falls back to outbox table on bus failure), EventBundleOutboxDispatcher (same for EventBundle), OutboxWorker (hosted service that retries unpublished outbox rows on a polling interval), NullOutboxLock + RedisOutboxLock (IOutboxLock implementations — default no-op for single-instance deployments, Redis-leased distributed lock for multi-replica setups)
Messaging/ RabbitMqBusIMessageBus over RabbitMQ. Azure Service Bus ships as the sibling Stratara.Outbox.AzureServiceBus package.
Mediator/ MediatorCommandWorker (hosted service that subscribes to the command topic and dispatches into the in-process IMediator)
Projections/ ProjectionReplayState (Redis-backed concrete IProjectionReplayState; dispatchers skip publishing while replay is active), ProjectionReplayOptions (how long the replay marking survives without renewal)
DependencyInjection/ AddOutboxDispatcher(), AddOutboxWorker(IConfiguration), AddRedisOutboxLock() (opt-in distributed lock), AddProjectionReplayState(), AddMediatorWorker(), AddMessaging()
Diagnostics/Extensions/ LoggerOutboxExtensions, LoggerMessagingExtensions (source-generated logger surfaces)

Quick start

// In your API host:
builder.AddMessaging();                          // IMessageBus + MessagingOptions binding
builder.Services
    .AddOutboxDispatcher()                       // CommandOutboxDispatcher + EventBundleOutboxDispatcher + ProjectionReplayState
    .AddOutboxWorker(builder.Configuration);     // OutboxWorker hosted service (only if this host owns retries)

// In your command worker:
builder.Services
    .AddMediatorWorker();                        // MediatorCommandWorker hosted service

The dispatchers consult IProjectionReplayState.IsReplayActive before each publish and skip dispatch (writing to the outbox table only) while a replay is in progress. They also record the outbox.published counter for what the broker accepted — the worker counts nothing, because only the dispatcher knows what went out.

The replay marking and its progress counters are held on the lease configured by ProjectionReplayOptions.LeaseSeconds (default 300), which the replay renews every time it reports progress. A replay whose host is killed stops renewing it and the marking lapses on its own, instead of suppressing publication indefinitely. AddProjectionReplayState() registers the options with their defaults; override with services.Configure<ProjectionReplayOptions>(...). Set it longer than the slowest stretch between two progress reports — too short lets the marking lapse while the replay is still running.

A drain cycle takes one batch of each kind and ends. Rows the broker would not accept stay in the table for the next interval; a cycle never re-reads what it just failed to publish, so an unreachable broker or a suppressed drain cannot turn a cycle into a loop over the same rows.

Multi-instance outbox workers

AddOutboxWorker registers NullOutboxLock as the default IOutboxLock — a no-op that preserves the single-instance assumption. For multi-replica deployments call AddRedisOutboxLock() afterwards; it replaces the no-op with a Redis-leased lock (SET stratara:outbox:lock NX EX) so only one replica drains at a time:

builder.AddCaching();                              // registers IConnectionMultiplexer
builder.Services
    .AddOutboxDispatcher()
    .AddOutboxWorker(builder.Configuration)
    .AddRedisOutboxLock();                         // multi-replica safe

The lease defaults to 60 s (OutboxOptions.LockLeaseSeconds). Tune it so it exceeds the worst-case drain duration; otherwise the lock can expire mid-cycle and a peer may start a concurrent drain. Outbox semantics are still at-least-once, so a duplicate publish is recoverable provided handlers stay idempotent.

Dependencies

  • Stratara.Abstractions — for ICommand, IEvent, IMessageBus, ICommandOutboxDispatcher, IEventBundleOutboxDispatcher, IProjectionReplayState, IMessagingIdentifier, IWriteUnitOfWork (used at runtime via the outbox repository).
  • Stratara.Contracts — for EventBundle + CommandEnvelope messages.
  • Stratara.MediatorMediatorCommandWorker dispatches into the in-process IMediator.
  • Stratara.Sessions — dispatcher hydrates CommandEnvelope from the current session context.
  • Stratara.Shared — for messaging primitives, resilience pipeline names, mapping helpers, and the diagnostics base.
  • RabbitMQ.Client, StackExchange.Redis (replay-state + optional outbox-lock).
  • Microsoft.Extensions.Hosting.Abstractions + Microsoft.Extensions.Options.ConfigurationExtensions — for hosted services + options binding.

The outbox dispatcher persists rows through IWriteUnitOfWork.CreateOutboxRepository — that interface lives in Stratara.Abstractions, but the concrete implementation comes from Stratara.EventSourcing.EntityFrameworkCore. Reference that package alongside this one to get a working stack.

Product Compatible and additional computed target framework versions.
.NET net10.0 is compatible.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-windows was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (2)

Showing the top 2 NuGet packages that depend on Stratara.Outbox.RabbitMQ:

Package Downloads
Stratara.Infrastructure

Infrastructure glue for the Stratara framework — authorization decorators, configuration providers, and DI composition helpers that wire Mediator, Outbox, Identity, and EF Core into a hosted app.

Stratara.EventSourcing.WorkerDefaults

Worker-host wiring composites for the Stratara event-sourced stack. IHostApplicationBuilder extensions (AddBackendServices, AddCommandWorkerServices, AddHeavyCommandWorkerServices, AddEventProjectionWorkerServices, AddEventStreamHashWorkerServices, AddSagaWorkerServices, AddOutboxWorkerServices) bundle the per-concern DI calls so each worker host opts in with one line.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last Updated
4.0.3 35 9/3/2026
4.0.2 89 9/3/2026
4.0.1 97 9/2/2026
4.0.0 150 8/31/2026
4.0.0-preview.1 58 8/31/2026
3.4.0 144 8/28/2026
3.3.0 117 8/25/2026
3.2.3 130 8/22/2026
3.2.2 137 8/14/2026
3.2.1 144 8/2/2026
3.2.0 137 7/18/2026
3.1.7 150 7/1/2026
3.1.6 568 6/22/2026
3.1.5 148 6/22/2026
3.1.4 151 6/15/2026
3.1.3 152 6/10/2026
3.1.2 170 6/5/2026
3.1.1 226 6/1/2026
3.1.0 150 5/30/2026
3.0.23 139 5/28/2026

Three fixes to the same complaint: a host composed exactly as the documentation describes did not
start. Each one was a registration the composites assumed somebody else had made — a tracer, a unit
of work, a Redis connection — and each is now made by the registration that needs it. Nothing that
already worked changes: every fix defers to a registration the host makes itself, in either order,
so the lines a working host added to get past these gaps can simply be deleted. Additive on every
published surface.

### Fixed

- **A host without Redis starts and dispatches.** Every composite that carries a dispatcher
 registered the projection-replay state, and its only implementation took a Redis connection that
 no composite registers, so a host composed as documented failed at its first dispatch unless it
 also ran Redis and called `AddCaching()`. `AddProjectionReplayState()` now chooses at first
 resolution: with a registered `IConnectionMultiplexer` the Redis-backed state as before, without
 one an in-process state with the same lease semantics — and a warning, once at start-up
 (`104_012`), that replay coordination is confined to that process, so a replay requested there
 suppresses publication there only. A deployment whose replay must reach several hosts registers
 the shared connection, in either order. Redis-backed hosts observe no change.
- **Registering a store context now registers its unit of work.**
 `AddNpgsqlWriteDbContextFactory<T>()` registered the context factory, the context and the default
 connection resolver but not the `IWriteUnitOfWork` that the event source, the outbox dispatcher and
 the command worker take from the container — and nothing else in the published packages did, so a
 host composed exactly as documented failed at its first command with a dependency-injection error.
 The write registration now try-adds a scoped `IWriteUnitOfWork` over its context, and
 `AddNpgsqlReadDbContextFactory<T>()` try-adds `IProjectionsUnitOfWork` and `IReadUnitOfWork`
 likewise. A unit of work the host registers itself, before or after, is still the one used; a
 hand-written registration can simply be deleted.
- **`AddMediator()` no longer requires the host to register an OpenTelemetry `Tracer`.** The
 mediator traces every dispatch and obtained its tracer from the host, but nothing registered one,
 so a host that called `AddMediator()` and nothing else failed at the first resolve of `IMediator`.
 `AddMediator()` now registers a fallback that emits the dispatch spans from the framework's
 `Stratara.Application` activity source — a host that subscribes to framework telemetry sees them,
 a host that subscribes to nothing pays for nothing. A `Tracer` the host registers, before or after
 `AddMediator()`, is still the one used, so no existing host changes behaviour; the registration
 line can simply be deleted. The samples, the README and the package README no longer carry it.