在.NET Core 中使用Quartz.NET

Quartz.NET是功能齐全的开源作业调度系统,可用于最小的应用程序到大型企业系统。

Quartz.NET具有三个主要概念:

•job:运行的后台任务•trigger:控制后台任务运行的触发器。•scheduler:协调job和trigger

在.NET Core 中使用Quartz.NET_第1张图片

ASP.NET Core通过托管服务对运行“后台任务”具有良好的支持,托管服务在ASP.NET Core应用程序启动时启动,并在应用程序生存期内在后台运行,Quartz.NET版本3.2.0通过Quartz.Extensions.Hosting包引入了对该模式的直接支持,Quartz.Extensions.Hosting可以与ASP.NET Core应用程序一起使用,也可以与基于“通用主机”的工作程序服务一起使用。

虽然.NET Core可以创建“定时”后台服务(例如,每10分钟运行一次任务),但Quartz.NET提供了更为强大的解决方案, 通过使用Cron表达式,您可以确保任务在特定时间(例如,凌晨2:30)运行,或仅在特定的几天运行,或这些时间的任意组合。Quartz.NET还允许您以集群方式运行应用程序的多个实例,以便在任何时候都只能运行一个实例。

安装Quartz.NET

Quartz.NET是一个.NET Standard 2.0 NuGet软件包,所以大部分项目都是支持的,你可以运行安装命令,dotnet add package Quartz.Extensions.Hosting,或者在NNuget可视化安装,如果查看该项目的.csproj,应该是下边这样:




  
    net5.0
    dotnet-QuartzWorkerService-9D4BFFBE-BE06-4490-AE8B-8AF1466778FD
  


  
    
    
  

安装完成以后,这个包会自动安装 Quartz.NET包,接下来,我们需要在我们的应用程序中注册Quartz服务和Quartz 。

添加Quartz.NET hosted service

修改Program.cs,注册服务

public class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }


    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureServices((hostContext, services) =>
            {
                // Add the required Quartz.NET services
                services.AddQuartz(q =>  
                {
                    // Use a Scoped container to create jobs. I'll touch on this later
                    q.UseMicrosoftDependencyInjectionScopedJobFactory();
                });


                // Add the Quartz.NET hosted service


                services.AddQuartzHostedService(
                    q => q.WaitForJobsToComplete = true);


                // other config
            });
}

UseMicrosoftDependencyInjectionScopedJobFactory(),这个地方告诉Quartz.NET注册一个IJobFactory,然后从DI容器中获取Job,这样也可以使用 Scoped 类型的服务。

WaitForJobsToComplete():当程序关闭时,此设置可确保Quartz.NET在退出之前等待Job正常结束。

如果现在运行您的应用程序,您将看到Quartz服务启动,并将有很多日志输出到控制台:

info: Quartz.Core.SchedulerSignalerImpl[0]
      Initialized Scheduler Signaller of type: Quartz.Core.SchedulerSignalerImpl
info: Quartz.Core.QuartzScheduler[0]
      Quartz Scheduler v.3.2.3.0 created.
info: Quartz.Core.QuartzScheduler[0]
      JobFactory set to: Quartz.Simpl.MicrosoftDependencyInjectionJobFactory
info: Quartz.Simpl.RAMJobStore[0]
      RAMJobStore initialized.
info: Quartz.Core.QuartzScheduler[0]
      Scheduler meta-data: Quartz Scheduler (v3.2.3.0) 'QuartzScheduler' with instanceId 'NON_CLUSTERED'
  Scheduler class: 'Quartz.Core.QuartzScheduler' - running locally.
  NOT STARTED.
  Currently in standby mode.
  Number of jobs executed: 0
  Using thread pool 'Quartz.Simpl.DefaultThreadPool' - with 10 threads.
  Using job-store 'Quartz.Simpl.RAMJobStore' - which does not support persistence. and is not clustered.


info: Quartz.Impl.StdSchedulerFactory[0]
      Quartz scheduler 'QuartzScheduler' initialized
info: Quartz.Impl.StdSchedulerFactory[0]
      Quartz scheduler version: 3.2.3.0
info: Quartz.Core.QuartzScheduler[0]
      Scheduler QuartzScheduler_$_NON_CLUSTERED started.
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
...

现在,您已经将Quartz作为托管服务运行在您的应用程序中,但是现在还没有添加需要运行的Job。

创建一个IJob

这个地方我创建一个简单的服务,并且我可以从构造函数中获取服务。

using Microsoft.Extensions.Logging;
using Quartz;
using System.Threading.Tasks;


[DisallowConcurrentExecution]
public class HelloWorldJob : IJob
{
    private readonly ILogger _logger;
    public HelloWorldJob(ILogger logger)
    {
        _logger = logger;
    }


    public Task Execute(IJobExecutionContext context)
    {
        _logger.LogInformation("Hello world!");
        return Task.CompletedTask;
    }
}

我还用[DisallowConcurrentExecution]特性,防止Quartz.NET尝试同时运行同一个作业。

设置Job

这个地方通常使用Cron表达式,来设置job的执行时间。

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureServices((hostContext, services) =>
        {
            services.AddQuartz(q =>  
            {
                q.UseMicrosoftDependencyInjectionScopedJobFactory();


                // Create a "key" for the job
                var jobKey = new JobKey("HelloWorldJob");


                // Register the job with the DI container
                q.AddJob(opts => opts.WithIdentity(jobKey));


                // Create a trigger for the job
                q.AddTrigger(opts => opts
                    .ForJob(jobKey) // link to the HelloWorldJob
                    .WithIdentity("HelloWorldJob-trigger") // give the trigger a unique name
                    .WithCronSchedule("0/5 * * * * ?")); // run every 5 seconds


            });
            services.AddQuartzHostedService(q => q.WaitForJobsToComplete = true);
            // ...
        });

现在运行应用程序,您将看到和以前相同的启动消息,然后每隔5秒钟就会看到HelloWorldJob写入控制台的信息:

在.NET Core 中使用Quartz.NET_第2张图片

将配置提取到appsettings.json

一般情况,我们都不会把cron表达式写死在代码中,一般是设置在appsettings.json中

{
  "Quartz": {
    "HelloWorldJob": "0/5 * * * * ?"
  }
}

为了更简单的注册服务,这个地方我简单做了一个封装,这样也更灵活。

public static class ServiceCollectionQuartzConfiguratorExtensions
{
    public static void AddJobAndTrigger(
        this IServiceCollectionQuartzConfigurator quartz,
        IConfiguration config)
        where T : IJob
    {
        // Use the name of the IJob as the appsettings.json key
        string jobName = typeof(T).Name;


        // Try and load the schedule from configuration
        var configKey = $"Quartz:{jobName}";
        var cronSchedule = config[configKey];


        // Some minor validation
        if (string.IsNullOrEmpty(cronSchedule))
        {
            throw new Exception($"No Quartz.NET Cron schedule found for job in configuration at {configKey}");
        }


        // register the job as before
        var jobKey = new JobKey(jobName);
        quartz.AddJob(opts => opts.WithIdentity(jobKey));


        quartz.AddTrigger(opts => opts
            .ForJob(jobKey)
            .WithIdentity(jobName + "-trigger")
            .WithCronSchedule(cronSchedule)); // use the schedule from configuration
    }
}

然后修改Program.cs,然后使用扩展方法:

public class Program
{
    public static void Main(string[] args) => CreateHostBuilder(args).Build().Run();


    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureServices((hostContext, services) =>
            {
                services.AddQuartz(q =>
                {
                    q.UseMicrosoftDependencyInjectionScopedJobFactory();


                    // Register the job, loading the schedule from configuration
                    q.AddJobAndTrigger(hostContext.Configuration);
                });


                services.AddQuartzHostedService(q => q.WaitForJobsToComplete = true);
            });
}

再次运行该应用程序将提供相同的输出:Job每5秒输入一次信息。

原文作者: andrewlock 

原文链接: https://andrewlock.net/using-quartz-net-with-asp-net-core-and-worker-services/[1]

最后

欢迎扫码关注我们的公众号 【全球技术精选】,专注国外优秀博客的翻译和开源项目分享,也可以添加QQ群 897216102

在.NET Core 中使用Quartz.NET_第3张图片

References

[1] https://andrewlock.net/using-quartz-net-with-asp-net-core-and-worker-services/: "https://andrewlock.net/using-quartz-net-with-asp-net-core-and-worker-services/"

你可能感兴趣的:(java,docker,python,linux,区块链)