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ForgeTrust.AppSurface.Workers

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ForgeTrust.AppSurface.Workers defines host-neutral contracts for durable worker chains and projection repair.

Release Guidance

AppSurface ships as a coordinated package family. Before installing this package from a prerelease feed, check the package chooser and release hub for current release risk, migration guidance, and readiness.

What It Includes

  • AppSurfaceWorkersModule, a passive module that declares no queue, storage, endpoint, or background worker infrastructure.
  • IDurableWorkerProjectionContract<TWork,TResult,TProjection> for claim, completion, single-projection repair, and bounded pending-projection repair.
  • IDurableWorkerExecutor<TWork,TResult> for the side-effecting executor activity that host runtimes schedule only after a claim succeeds.
  • DurableWorkerEnvelope<TPayload>, DurableWorkerCorrelation, and DurableWorkerDiagnostic for typed outcomes and privacy-safe repair diagnostics.
  • DurableWorkerExecutionIdentity for native runtimes that must keep immutable activity/provider identity separate from attempt, lease, scope, and runtime epochs.
  • Stable outcome and retryability enums for durable adapters and application logs.
  • DurableWorkerMetadataSafety for rejecting unsafe diagnostic metadata before it becomes durable or user-visible.

What It Does Not Include

  • Durable Task worker or client hosting.
  • EF Core, Postgres, or any queue/scheduler runtime.
  • Storage schemas or migrations.
  • ASP.NET Core endpoints, authentication handlers, webhooks, UI, or Semantic Kernel.

Contract Shape

Worker chains split durable behavior into three app-owned responsibilities:

  1. TryClaimAsync decides whether executor activity may be scheduled.
  2. CompleteAsync records the terminal execution fact produced by executor activity.
  3. ReconcileProjectionAsync and ReconcilePendingProjectionsAsync update visible projections from durable completion facts without re-running executor activity.

This package does not decide where the facts live. A host can store them in its existing database, emit them from Durable Task activities, or adapt another persistence layer later. The first AppSurface runtime adapter is DurableTask-first; EF/Postgres runtime ownership is intentionally out of scope.

The native AppSurface Durable runtime reuses IDurableWorkerExecutor<TWork,TResult> and the typed envelope, but it does not call this package's legacy TryClaimAsync or CompleteAsync projection-authority methods. PostgreSQL remains the sole claim, effect-permit, and terminal-fact authority.

Native execution identity

DurableWorkerEnvelope<TPayload>.ExecutionIdentity is optional for compatibility with existing adapters. The native runtime creates envelopes with DurableWorkerEnvelope<TPayload>.CreateNative and always supplies the identity before provider I/O. Its ActivityId and ProviderKey remain stable across retries; its AttemptNumber, LeaseGeneration, ScopeGeneration, and RuntimeEpoch fence one exact execution observation.

Do not derive a provider idempotency key from Correlation.AttemptId, an attempt number, or a lease generation. Doing so turns a retry into a different provider operation and defeats ProviderKeyed safety. Projection repair may inspect execution identity, but must never treat it as authorization to invoke the executor again.

Privacy-Safe Diagnostics

Metadata and diagnostics are meant to be durable and visible in repair reports, so they must contain only safe values:

  • Stable reason codes and opaque identifiers.
  • Counts, states, and bounded labels.
  • Safe problem, cause, and fix guidance.

Do not put provider URLs, OAuth tokens, credentials, raw payloads, prompts, model output, email bodies, attachments, child-sensitive text, or other unclassified sensitive content into metadata.

Projection Repair

Projection repair is a recovery path, not an executor path. Repair code should read durable completion facts, update visible state, and return Reconciled, Noop, StaleFence, Conflict, or Unrecoverable outcomes. It should not call IDurableWorkerExecutor<TWork,TResult>.

Use DurableWorkerProjectionRepairRequest to keep repair scans bounded by staleness and batch size.