在.NET Core 中实现健康检查

.NET Core中提供了开箱即用的运行状况检查，首先，我将在.NET Core API应用程序中执行运行状况检查，接下来，我们将使用DbContext集成SQL Server或数据库的运行状况检查，最后是如何实现自定义服务的运行状况检查。

在ASP.NET Core中实现健康检查

要实现运行状况检查，您需要在项目中安装

Microsoft.AspNetCore.Diagnostics.HealthChecks

接下来，在

ConfigureServices

public void ConfigureServices(IServiceCollection services)
{
services.AddHealthChecks();
services.AddControllers();
}

然后修改

Configure

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
endpoints.MapHealthChecks("/health");
});
}

现在，准备工作完成，运行程序然后访问 /health, 您将看到下边结果：

HealthCheckService

.NET Core提供了一个HealthCheckService类，我们可以把健康检查的放到我们的控制器中，就像这样：

public class HealthController : ControllerBase
{
private readonly ILogger<HealthController> _logger;
private readonly HealthCheckService _healthCheckService;
public HealthController(ILogger<HealthController> logger,
HealthCheckService healthCheckService)
{
_healthCheckService = healthCheckService;
_logger = logger;
}

[HttpGet]
public async Task<IActionResult> Get()
{
var report = await _healthCheckService.CheckHealthAsync();

return report.Status == HealthStatus.Healthy ? Ok(report) :
StatusCode((int)HttpStatusCode.ServiceUnavailable, report);
}
}

现在，如果您尝试访问/health，您将看到相同的结果。

接下来，我们将实现数据库运行状态检查：

EntityFramework Core 健康检查

首先，还是需要安装

Microsoft.Extensions.Diagnostics.HealthChecks.EntityFrameworkCore

接下来，我们拿到数据库上下文，然后修改代码：

public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
services.AddApiVersioning();
}

然后，运行程序，现在访问 /health 返回的结果是这样：

IHealthCheck

一些情况下，默认的健康检查可能不满足我们的需求，那么可以继承 IHealthCheck 接口，自定义我们的健康检查的逻辑。

public class ApiHealthCheck : IHealthCheck
{
private readonly IHttpClientFactory _httpClientFactory;

public ApiHealthCheck(IHttpClientFactory httpClientFactory)
{
_httpClientFactory = httpClientFactory;
}
public async Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context,
CancellationToken cancellationToken = default)
{
using (var httpClient = _httpClientFactory.CreateClient())
{
var response = await httpClient.GetAsync("https://your-api-service.endpoint");
if (response.IsSuccessStatusCode)
{
return HealthCheckResult.Healthy($"API is running.");
}

return HealthCheckResult.Unhealthy("API is not running");
}
}
}

然后修改代码如下：

public void ConfigureServices(IServiceCollection services)
{
services.AddHealthChecks()
.AddDbContextCheck<WeatherForecastDbContext>()
.AddCheck<ApiHealthCheck>("ApiHealth");
services.AddControllers();
}

然后，运行程序，访问 /health,结果如下：