[Varshitha Bachu (bachuv)]

Summary

What changed?

• Add RestartAsync(string instanceId, string newInstanceId, string? version, CancellationToken cancellation) with four required arguments. The existing bool overload remains unchanged, including calls using default.
• Use the separate CloneInstance RPC for explicit target IDs and version overrides. The existing RestartInstanceRequest is unchanged.
• Restart using the source orchestration's original name and input without copying execution history. version: null uses the backend's restart default; version: "" explicitly selects an unversioned orchestration.
• Expose immediate source lineage through TaskOrchestrationContext.SourceInstanceId in both worker paths, preserving IDs as opaque strings, including dt: and dto: prefixes.
• Refresh the protobuf definitions and provenance, update coverage and the README example, and guard scheduling-log argument evaluation when Information logging is disabled.

string cloneId = await client.RestartAsync(
    "source-instance",
    "clone-instance",
    version: "v2",
    cancellation: CancellationToken.None);

Why is this change needed?

• Enable orchestration cloning with a caller-selected target ID, a version override, and immediate source lineage, supporting .NET isolated Durable Functions integration.

Issues / work items

• Resolves: N/A.
• Related: microsoft/durabletask-protobuf#82.

---

Project checklist

• Release notes are not required for the next release
  • Otherwise: Notes added to release_notes.md
• Backport is not required
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• All required tests have been added/updated (unit tests, E2E tests)
• Breaking change?
  • If yes:
    • Impact: N/A; existing API signatures and wire field numbers remain unchanged.
    • Migration guidance: No migration for existing callers. The new overload requires a backend supporting CloneInstance.

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AI-assisted code disclosure (required)

Was an AI tool used? (select one)

• No
• Yes, AI helped write parts of this PR (e.g., GitHub Copilot)
• Yes, an AI agent generated most of this PR

If AI was used:

• Tool(s): GitHub Copilot.
• AI-assisted areas/files: Client API and RPC handling, source metadata, worker property conversion, protobuf refresh, logging guard, tests, and documentation.
• What you changed after AI output: Iterated on review feedback to use the four-argument overload and separate clone RPC, preserve opaque source IDs, add the logging guard, and simplify the README.

AI verification (required if AI was used):

• I understand the code and can explain it
• I verified referenced APIs/types exist and are correct
• I reviewed edge cases/failure paths (timeouts, retries, cancellation, exceptions)
• I reviewed concurrency/async behavior
• I checked for unintended breaking or behavior changes

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Testing

Automated tests

• Result: Passed; 68 focused tests rerun against commit 844a78e.
• dotnet test .\test\Client\Grpc.Tests\Client.Grpc.Tests.csproj --no-restore --filter 'FullyQualifiedName~GrpcDurableTaskClientRestartTests|FullyQualifiedName~GrpcDurableTaskClientTests.ScheduleNewOrchestrationInstanceAsync' --verbosity quiet -clp:ErrorsOnly — Passed, 37 tests.
• dotnet test .\test\Worker\Grpc.Tests\Worker.Grpc.Tests.csproj --no-restore --filter 'FullyQualifiedName~GrpcOrchestrationRunnerTests|FullyQualifiedName~OnRunOrchestratorAsync_Properties_ExposeImmediateSource' --verbosity quiet -clp:ErrorsOnly — Passed, 27 tests.
• dotnet test .\test\Grpc.IntegrationTests\Grpc.IntegrationTests.csproj --no-restore --filter 'FullyQualifiedName~DurableTaskGrpcClientIntegrationTests.RestartAsync' --verbosity quiet -clp:ErrorsOnly — Passed, 4 tests.
• Coverage includes legacy default-literal calls, clone request/error handling, unsupported-server behavior without fallback, opaque source IDs during execution and replay, and unchanged date conversion for unrelated properties.
• The full solution suite and DTS emulator tests were not run.

Manual validation (only if runtime/behavior changed)

• Environment (OS, .NET version, components): Windows, .NET SDK 10.0.403; local SDK client/worker and in-process gRPC integration tests.
• Steps + observed results: No separate manual validation against a deployed Durable Functions or DTS backend was performed.
• Evidence (optional): Automated results above.

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Notes for reviewers

• No breaking change — the existing bool restart overload and its RPC contract remain unchanged. The new context member is virtual rather than abstract; serializer defaults are unchanged.
• The four-argument overload requires a backend supporting CloneInstance. Older servers return UNIMPLEMENTED, surfaced as NotSupportedException, without performing a legacy restart. The client never falls back to RestartInstance.
• A mismatched response instance ID causes InvalidOperationException. The client cannot independently verify whether a supporting backend honored a version override.
• SourceInstanceId identifies the immediate source when source and target IDs differ. It is separate from parent metadata and is not inherited by sub-orchestrations; same-ID lineage is backend-specific.
• The orchestration-service client shim does not implement the new overload.

[Copilot]

🟡 Changes recommended

The new RestartAsync overload makes previously valid default-literal calls fail to compile, while property unpacking can also lose backend-supplied lineage for date-like source IDs.

2 open issues

• Avoid ambiguous RestartAsync overloads for default literals · New
• Preserve source instance IDs as opaque strings during unpacking · New

What changed in this PR

This PR adds caller-selected restart IDs and optional version overrides to the Durable Task SDK, plus immediate source-instance metadata for cloned orchestrations.

Changes:

• Add restart options and gRPC handling, including validation and returned-ID checks.
• Expose SourceInstanceId and forward request properties through the standalone worker.
• Add focused tests and document usage, backend requirements, and protobuf provenance.

File	Description
test/​Worker/​Grpc.Tests/​GrpcOrchestrationRunnerTests.cs	Test lineage during execution and replay.
test/​Worker/​Grpc.Tests/​GrpcDurableTaskWorkerTests.cs	Test standalone worker lineage forwarding.
test/​Worker/​Core.Tests/​Shims/​TaskOrchestrationContextWrapperTests.cs	Test property-backed source metadata.
test/​Client/​Grpc.Tests/​GrpcDurableTaskClientRestartTests.cs	Cover restart options, validation, compatibility, and errors.
src/​Worker/​Grpc/​GrpcDurableTaskWorker.Processor.cs	Forward request properties into orchestration contexts.
src/​Grpc/​versions.txt	Record provenance of the imported protobuf patch.
src/​Grpc/​orchestrator_service.proto	Add optional target-ID and version fields.
src/​Client/​Grpc/​GrpcDurableTaskClient.cs	Implement explicit restart options and shared error handling.
src/​Client/​Core/​RestartOrchestrationOptions.cs	Define target-ID and version options.
src/​Client/​Core/​DurableTaskClient.cs	Add the virtual restart-options overload.
src/​Abstractions/​TaskOrchestrationContext.cs	Expose immediate source-instance metadata.
README.md	Document cloning usage and compatibility limitations.

_{Review effort: Balanced}

[Bernd Verst (berndverst)]

The SDK-side approach largely accomplishes the stated goal for a supporting backend, and I don't see a material new performance regression. The property-conversion comparison was an isolated microbenchmark with the default null logger factory, not an end-to-end throughput benchmark. Backend support remains a deployment prerequisite, as documented.

Requesting changes for the two existing inline findings, both independently reproduced: restart overload source compatibility and opaque source-ID preservation.

The unrelated, pre-existing logging improvement request is now a non-blocking file-level comment.

[Copilot]

🟡 Changes recommended

The PR description advertises an unimplemented restart API and outdated compatibility behavior, so callers following it would encounter compilation errors and misleading older-server guidance.

1 open issue

• Update PR description to match the implemented restart API · New

2 resolved since last review

• Avoid ambiguous RestartAsync overloads for default literals
• Preserve source instance IDs as opaque strings during unpacking

_{Review effort: Balanced}