Diagnostics/samples/HealthChecksSample/LivenessProbeStartup.cs

69 строки
3.0 KiB
C#

using System;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Diagnostics.HealthChecks;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
namespace HealthChecksSample
{
// Pass in `--scenario liveness` at the command line to run this sample.
public class LivenessProbeStartup
{
public void ConfigureServices(IServiceCollection services)
{
// Registers required services for health checks
services
.AddHealthChecks()
.AddCheck<SlowDependencyHealthCheck>("Slow", failureStatus: null, tags: new[] { "ready", });
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
// This will register the health checks middleware twice:
// - at /health/ready for 'readiness'
// - at /health/live for 'liveness'
//
// Using a separate liveness and readiness check is useful in an environment like Kubernetes
// when an application needs to do significant work before accepting requests. Using separate
// checks allows the orchestrator to distinguish whether the application is functioning but
// not yet ready or if the application has failed to start.
//
// For instance the liveness check will do a quick set of checks to determine if the process
// is functioning correctly.
//
// The readiness check might do a set of more expensive or time-consuming checks to determine
// if all other resources are responding.
//
// See https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-probes/ for
// more details about readiness and liveness probes in Kubernetes.
//
// In this example, the liveness check will us an 'identity' check that always returns healthy.
//
// In this example, the readiness check will run all registered checks, include a check with a
// long initialization time (15 seconds).
// The readiness check uses all registered checks with the 'ready' tag.
app.UseHealthChecks("/health/ready", new HealthCheckOptions()
{
Predicate = (check) => check.Tags.Contains("ready"),
});
// The liveness filters out all checks and just returns success
app.UseHealthChecks("/health/live", new HealthCheckOptions()
{
// Exclude all checks, just return a 200.
Predicate = (check) => false,
});
app.Run(async (context) =>
{
await context.Response.WriteAsync("Go to /health/ready to see the readiness status");
await context.Response.WriteAsync(Environment.NewLine);
await context.Response.WriteAsync("Go to /health/live to see the liveness status");
});
}
}
}