我如何在 .net core 3.0 中执行一次工作者服务?
How can i execute a worker service once in .net core 3.0?
我在 .net core 3.0 中使用服务工作者模板。
我想做的是仅在我的参数 "ExecuteOnce" 设置为 true 时执行此服务一次
在 appsettings.json .
Program.cs :
public class Program
{
public static IServiceProvider Services { get; set; }
public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureAppConfiguration((hostContext, config) =>
{
if (hostContext.HostingEnvironment.IsProduction())
config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);
else
config.AddJsonFile("appsettings.Development.json", optional: true, reloadOnChange: true);
config.SetBasePath(Directory.GetCurrentDirectory());
})
.ConfigureServices((hostContext, services) =>
{
services.AddHostedService<Worker>();
});
public static void Main(string[] args)
{
CreateHostBuilder(args).Build().Run();
}
}
Worker.cs :
public class Worker : BackgroundService
{
private readonly IConfiguration _configuration;
public Worker(ILogger<Worker> logger, IConfiguration configuration)
{
_configuration = configuration;
}
public override Task StartAsync(CancellationToken cancellationToken)
{
return base.StartAsync(cancellationToken); ;
}
public override Task StopAsync(CancellationToken cancellationToken)
{
return base.StopAsync(cancellationToken);
}
protected override async Task ExecuteAsync(CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
// Bit of logic here...
if (_configuration.GetValue<bool>("TaskConfig:ExecuteOnce"))
// TODO HERE : stop this service
else
await Task.Delay(_configuration.GetValue<int>("TaskConfig:TaskDelayMs"), new CancellationToken());
}
}
}
我试过:
-等待 Task.TaskCompleted
-打破循环
-调用 StopAsync()
但是每次我偶然发现一些限制,实现它的正确方法是什么?
使用 IHostApplicationLifetime - 通过它您可以告诉您的应用程序自行关闭。
public class Worker : BackgroundService
{
private readonly IHostApplicationLifetime _hostLifetime;
public Worker(IHostApplicationLifetime hostLifetime)
{
_hostLifetime = hostLifetime;
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
while (true)
{
DoWork();
if (RunOnlyOnce())
{
_hostLifetime.StopApplication();
}
}
}
}
我在 .net core 3.0 中使用服务工作者模板。 我想做的是仅在我的参数 "ExecuteOnce" 设置为 true 时执行此服务一次 在 appsettings.json .
Program.cs :
public class Program
{
public static IServiceProvider Services { get; set; }
public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureAppConfiguration((hostContext, config) =>
{
if (hostContext.HostingEnvironment.IsProduction())
config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);
else
config.AddJsonFile("appsettings.Development.json", optional: true, reloadOnChange: true);
config.SetBasePath(Directory.GetCurrentDirectory());
})
.ConfigureServices((hostContext, services) =>
{
services.AddHostedService<Worker>();
});
public static void Main(string[] args)
{
CreateHostBuilder(args).Build().Run();
}
}
Worker.cs :
public class Worker : BackgroundService
{
private readonly IConfiguration _configuration;
public Worker(ILogger<Worker> logger, IConfiguration configuration)
{
_configuration = configuration;
}
public override Task StartAsync(CancellationToken cancellationToken)
{
return base.StartAsync(cancellationToken); ;
}
public override Task StopAsync(CancellationToken cancellationToken)
{
return base.StopAsync(cancellationToken);
}
protected override async Task ExecuteAsync(CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
// Bit of logic here...
if (_configuration.GetValue<bool>("TaskConfig:ExecuteOnce"))
// TODO HERE : stop this service
else
await Task.Delay(_configuration.GetValue<int>("TaskConfig:TaskDelayMs"), new CancellationToken());
}
}
}
我试过: -等待 Task.TaskCompleted -打破循环 -调用 StopAsync()
但是每次我偶然发现一些限制,实现它的正确方法是什么?
使用 IHostApplicationLifetime - 通过它您可以告诉您的应用程序自行关闭。
public class Worker : BackgroundService
{
private readonly IHostApplicationLifetime _hostLifetime;
public Worker(IHostApplicationLifetime hostLifetime)
{
_hostLifetime = hostLifetime;
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
while (true)
{
DoWork();
if (RunOnlyOnce())
{
_hostLifetime.StopApplication();
}
}
}
}