Calculated break duration for Circuit breaker

[atawLee]

The issue or feature being addressed

#653

Details on the issue fix or feature implementation

• Added a FailureCount get property to CircuitBehavior to retrieve the count of failures.
• Introduced a private readonly field _breakDurationGenerator of type Func<BreakDurationGeneratorArguments, ValueTask<TimeSpan>>? to CircuitStateController for dynamic break duration generation.
• Enhanced the constructor of CircuitStateController with an overload to accommodate _breakDurationGenerator.
• Incorporated FailureCount into HealthInfo.
• Updated OpenCircuitFor_NeedsLock to assign the _blockedUntil value based on both the presence of breakDuration and the number of failures.

This new Pull Request is a continuation of the work on the GeneratorDuration branch. It includes all the changes previously submitted and any additional fixes required to align with the main branch.
#1715

I am currently working on improving the Test Coverage to ensure the robustness of the new features. This work is still in progress, and I will update this PR with the relevant changes as soon as they are ready.

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• I have included unit tests for the issue/feature
• I have successfully run a local build

[martintmk]

Looks good. Great work and thanks for contributing :)

[peter-csala]

@atawLee Is the related documentation purposefully left untouched (until v8.2.0 is not released)?

[martincostello]

I think that's just an oversight (it certainly is that I didn't notice we hadn't changed it).

[atawLee]

@peter-csala it seems there might have been an oversight regarding the documentation update. Could you please guide me on which specific documents need to be revised?

[peter-csala]

@atawLee

circuit-breaker.md + CircuitBreaker.cs

• Link
• Under the Usage section
  • Please add a new sample option (between optionsComplex and optionsShouldHandle) which demonstrates the usage of the BreakDurationGenerator
  • In order to do that extend the Usage method of the CircuitBreaker class
• Under the Defaults section
  • Please add a new row (between BreakDuration and OnClosed) which details the BreakDurationGenerator property
• Under the Diagrams section
  • You can add here a new subsection with a sequence diagram to demonstrate how CB dynamically generates break duration timespans
  • If you think that this use case is really similar to one of the existing sequence diagrams then simple ignore this
• Under the Anti-patterns section
  • Delete the Using different duration for breaks subsection
  • Delete the AntiPattern_SleepDurationGenerator method from the CircuitBreaker class

Tips

• Use the dotnet mdsnippets command to refresh the code snippets inside the markdown files
  • This will update the main readme.md file as well
• Use the dotnet docfx docs/docfx.json --serve command to check out locally the generated docfx pages under the http://localhost:8080/

[martincostello]

@atawLee Will you be able to raise a PR to make the documentation updates for your change?

[atawLee]

@martincostello Hi there, I'm currently working on the documentation updates for my change. I expect to be able to raise a Pull Request by the end of this week.

[adminnz]

There is an issue with this. When you call AddCircuitBreaker(options), having specified BreakDurationGenerator. It does not pass the generate to the CircuitStateController. So the resulting circuitbreaker will use the default 5 seconds fixed duration.

[martincostello]

@adminnz Thanks for reporting this. Would you mind creating a new issue with more details about your use case, then we can look at a fix.

[martincostello]

@adminnz I've copied your comment to a new issue #1850 - could you please add a bit more detail there?