PollyHealthChecks 1.0.1

PollyHealthChecks

ASP.NET Core health checks for Polly v8 circuit breakers.

Expose circuit breaker state as standard /health endpoint responses so load balancers, Kubernetes probes, and monitoring dashboards can act on the resilience state of your dependencies.

Install

dotnet add package PollyHealthChecks

Usage

1. Set up your circuit breaker with a CircuitBreakerStateProvider

using Polly.CircuitBreaker;

var stateProvider = new CircuitBreakerStateProvider();
var manualControl = new CircuitBreakerManualControl(); // optional

services.AddResiliencePipeline("downstream-api", builder =>
    builder.AddCircuitBreaker(new CircuitBreakerStrategyOptions
    {
        StateProvider = stateProvider,
        ManualControl = manualControl,  // optional
        FailureRatio = 0.5,
        SamplingDuration = TimeSpan.FromSeconds(10),
        MinimumThroughput = 5,
        BreakDuration = TimeSpan.FromSeconds(30)
    }));

2. Register the health check

using PollyHealthChecks;

services.AddHealthChecks()
    .AddPollyCircuitBreaker("downstream-api", stateProvider);

3. Map the health endpoint

app.MapHealthChecks("/health");

Example response

When the circuit is closed (normal operation):

{ "status": "Healthy", "entries": { "downstream-api": { "status": "Healthy", "description": "Circuit breaker is closed." } } }

When the circuit is open (tripping):

{ "status": "Unhealthy", "entries": { "downstream-api": { "status": "Unhealthy", "description": "Circuit breaker is open." } } }

State mapping

Options

services.AddHealthChecks()
    .AddPollyCircuitBreaker(
        name: "downstream-api",
        stateProvider: stateProvider,
        failureStatus: HealthStatus.Degraded,  // override open/isolated status
        tags: ["ready", "live"]);              // for filtered health checks

Multiple circuit breakers

services.AddHealthChecks()
    .AddPollyCircuitBreaker("payments-api", paymentsStateProvider)
    .AddPollyCircuitBreaker("inventory-api", inventoryStateProvider, failureStatus: HealthStatus.Degraded)
    .AddPollyCircuitBreaker("auth-api", authStateProvider, tags: ["ready"]);

License

MIT