CHANGELOG.md

Change Log

Unreleased

• Request Caching -- Will likely be implemented using xPike caching interfaces and rely on any existing caching you may have in place, since xPike already supports client-side caching with proper invalidation.
• Dashboard -- Will likely never be included in NHystrix. Instead, the ability to report circuit breaker state to an APM of your choice will be included.

[0.7.0]

Added

Support for HttpClientFactory in Asp.Net Core.

[0.6.0]

Beaking changes

Redesigned HystrixDelegatingHandler to use an instance of HttpHystrixCommand which subclasses HystrixCommand. This also required breaking changes to how HystrixCommands are created and executed. Most existing commands shouldn't break, but be aware their could be issues and test accordingly.

[0.5.1]

Bug Fixes

Fixed a bug in HystrixCommandGroup.AddCommandKey where multiple keys didn't get added.

[0.5.0]

Beaking changes

Extracted HttpClient support into its own library.

[0.4.0]

Changes

Support for .Net Core 3.0.

Multi-Targeted for older supported frameworks and tooling:

• net452
• net461
• netStandard2.0
• netCoreApp3.0

[0.3.0]

Added

Asychronous execution support using the IHystrixCommand.Queue() method. This method is non-blocking uses a producer/consumer pattern under the hood. A callback action can invoked when the command completes.

[0.2.0]

There are some pretty major breaking changes in this release as we bring more of the Hystrix functionality and design into the APIs. We've also deviated from the original Hystrix implementation a bit more and use typed exceptions rather than a single HystrixRuntimeException and an enum.

We'll try to keep breaking changes to a minimum going forward unless it's to fix a major design flaw or to greatly improve reliability, performance, and usability. No promises :) If breaking it makes it better, we'll do it. At least until we reach a 1.0 release.

Added

• A delegating message handler for HttpClient (HystrixDelegatingHandler) that implements
  • Circuit Breaker Pattern
  • Bulkhead Pattern
  • Metrics
• Expanded the IHystrixCircuitBreaker beyond the original Netflix version
• Typed Exceptions

Changes (non-breaking)

• Execute() and ExecuteAsync() methods now accept an optional request parameter. This allows a HystrixCommand to be a Singleton and the request passed into Execute() rather than the constructor.

Breaking Changes

• The circuit breaker properties have been refactored in to their own class CircuitBreakerOptions. The HystrixCommandProperties now has a property of type CircuitBreakerOptions. This eliminates confusion as to exactly which configuration properties directly affect the circuit breaker and only those options are passed to the HystrixCircuitBreaker on construction. We will likely do the same in metrics in a future release when metrics is built out further.

• Timeouts now throw a HystrixTimeoutException instead of a System.TimoutException. HystrixTimeoutException derives from HystrixRuntimeException and ensures the HystrixCommand doesn't double count when exceptions are rethrown.

• When fallback is disabled, the original exception is wrapped in a HystrixRuntimeExtension or subclass rather than just throwing the original exception.

• HystrixCommand has an additional generic type parameter for the request.

[0.1.0] - Initial release

• HystrixCommand with:
  • Circuit Breaker Pattern (https://docs.microsoft.com/en-us/azure/architecture/patterns/circuit-breaker)
  • Bulkhead Pattern (https://docs.microsoft.com/en-us/azure/architecture/patterns/bulkhead)
  • Timeouts
• Minimum metrics required to support the Circuit Breaker