Service Lifetime Events

[ledjon-behluli]

close #9771

Microsoft Reviewers: Open in CodeFlow

[ledjon-behluli]

@ReubenBond addressed the comments, PTAL!

WDYT about this, I am unsure, but lean more towards (a)waiting indefinitely

[ReubenBond]

@ledjon-behluli I think relying on them respecting the CT is ok (even if not defensive)

[ledjon-behluli]

@ReubenBond Added proper tests & removed the toy/test console app. We should consider not having the TerminateOnError and control it within the component i.e. Starting events should terminate, and while stopping we log and swallow, but other than that this is now ready AFAIC.

P.s: I do not have a strong opinion on the matter of TerminateOnError being an internal thing, or left to the user.

[shacal]

Yes please!

[Copilot]

Pull request overview

This PR introduces a new service lifetime event system for Orleans, providing a cleaner API for observing and participating in client/silo lifecycle stages. The implementation adds IServiceLifetime with three stages (Started, Stopping, Stopped) that allow callbacks to be registered and executed at specific points in the service lifecycle.

Key changes:

• New IServiceLifetime and IServiceLifetimeStage interfaces providing callback registration and cancellation token support
• ServiceLifetimeStage implementation handling callback execution, error handling, and late registrations
• Registration in both client and silo service containers with comprehensive test coverage

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/Orleans.Core/Lifecycle/ServiceLifetimeStage.cs	Core implementation of lifecycle stages with callback management, error handling, and thread-safe registration
src/Orleans.Core/Lifecycle/ServiceLifetime.cs	Main service lifetime coordinator that wires up Started, Stopping, and Stopped stages to the underlying lifecycle observable
src/Orleans.Runtime/Hosting/DefaultSiloServices.cs	Registers ServiceLifetime for silo lifecycle with dependency injection (also reorganizes using statements alphabetically)
src/Orleans.Core/Core/DefaultClientServices.cs	Registers ServiceLifetime for client lifecycle with dependency injection
test/NonSilo.Tests/ServiceLifetimeTests.cs	Comprehensive test suite covering callback execution, cancellation, error handling, late registration, and concurrency scenarios