Stratara.Projections 4.0.3

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dotnet add package Stratara.Projections --version 4.0.3
                    
NuGet\Install-Package Stratara.Projections -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.Projections" Version="4.0.3" />
                    
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageVersion Include="Stratara.Projections" Version="4.0.3" />
                    
Directory.Packages.props
<PackageReference Include="Stratara.Projections" />
                    
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.Projections --version 4.0.3
                    
#r "nuget: Stratara.Projections, 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.Projections@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.Projections&version=4.0.3
                    
Install as a Cake Addin
#tool nuget:?package=Stratara.Projections&version=4.0.3
                    
Install as a Cake Tool

Stratara.Projections

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

License: MIT.

Projection runtime for the Stratara event-sourced stack. Discovers IProjection implementations in the consumer's application assemblies, dispatches event bundles to them, and applies the resulting change sets atomically via the read-model repository layer.

What's in the box

Folder Contents
Services/ The runtime, all internal: ProjectionManager (event-bundle → matching projection-handlers fan-out), ProjectionHandler (invokes a projection's matching methods), ProjectionMethodInvoker (reflection-cached method-pointer dispatch into consumer projections). You implement IProjection; these drive it
Multitenancy/ TenantProjection — the framework's own opinionated tenant aggregate projection. Skip the registration if your application has its own tenancy model
Diagnostics/Extensions/ Source-generated LoggerProjectionExtensions, LoggerChangeSetExtensions, LoggerUpdateExtensions — typed [LoggerMessage] surfaces under the Stratara.Projection.* / Stratara.ChangeSet.* / Stratara.Update.* event-ID bands

Quick start

// In your EventProjection worker:
builder.Services
    .AddProjectionWorker(builder.Configuration)                       // the runtime + hosted service
    .AddProjectionsFromAssemblyContaining<MyAppProjectionMarker>();   // your IProjection implementations

Then implement IProjection in your application assembly. The projection manager picks them up automatically.

Both calls are needed: AddProjectionsFromAssemblyContaining<T>() only registers your projections — AddProjectionWorker(IConfiguration) registers the manager, the invoker and the hosted service that consumes the event-bundle subscription. Without it nothing drives your projections. Most hosts get both from the AddEventProjectionWorkerServices() composite in Stratara.EventSourcing.WorkerDefaults.

No checkpoint store. Projections are driven push-wise off the event bus; the framework keeps no per-projection checkpoint, so there is no consumer-lag metric and no built-in resume-from-sequence. Replay is coordinated separately (see Stratara.Outbox.RabbitMQ's replay state).

Dependencies

  • Stratara.Contracts — for EventBundle + IEvent<T>.
  • Stratara.Domain — for the framework's Tenant aggregate (only consumed by TenantProjection).
  • Stratara.Shared — for change-tracking primitives, reflection cache, partitioning helpers, diagnostics base.
  • Microsoft.Extensions.Hosting.Abstractions + Microsoft.Extensions.Options.ConfigurationExtensions — for projection-worker checkpointing options.
  • JetBrains.Annotations — for static-analysis attributes on projection-handler conventions.
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.Projections:

Package Downloads
Stratara.EventSourcing.EntityFrameworkCore

EF Core persistence for the Stratara event-sourced stack on PostgreSQL — write-store, read-store, ASP.NET Identity store, shared conventions, value generators, and UnitOfWork primitives. Targets Npgsql with pgvector.

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 34 9/3/2026
4.0.2 90 9/3/2026
4.0.1 106 9/2/2026
4.0.0 154 8/31/2026
4.0.0-preview.1 58 8/31/2026
3.4.0 150 8/28/2026
3.3.0 125 8/25/2026
3.2.3 140 8/22/2026
3.2.2 143 8/14/2026
3.2.1 160 8/2/2026
3.2.0 150 7/18/2026
3.1.7 338 7/1/2026
3.1.6 578 6/22/2026
3.1.5 163 6/22/2026
3.1.4 177 6/15/2026
3.1.3 166 6/10/2026
3.1.2 173 6/5/2026
3.1.1 239 6/1/2026
3.1.0 158 5/30/2026
3.0.23 146 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.