2.3 KiB

Raw Blame History

Background Workers

Introduction

Background workers are used to execute some tasks in the background periodically.

Create a Background Worker

A background worker is a class that derives from the AsyncPeriodicBackgroundWorkerBase or PeriodicBackgroundWorkerBase class. Both base classes are derived from ISingletonDependency.

Status Checker

This example is used to simple check remote application status. Just suppose that, we want to check and store some web applications are running or not?

public class AppStatusService : ITransientDependency
{
    .
    .
    public void CheckAppStatus()
    {
        var ping = new System.Net.NetworkInformation.Ping();

        var result = ping.Send("www.github.com");

        // save the result
    }
    .
    .
}

Then create a background worker class that derived from the PeriodicBackgroundWorkerBase:

.
.
using Volo.Abp.BackgroundWorkers;

namespace Volo.Www.Application
{
    public class AppStatusCheckingWorker : PeriodicBackgroundWorkerBase
    {
        private readonly IAppStatusService _appStatusService;

        public AppStatusCheckingWorker(
            AbpTimer timer,
            IServiceScopeFactory scopeFactory, 
            IAppStatusService appStatusService)
            : base(timer, scopeFactory)
        {
            _appStatusService = appStatusService;
            Timer.Period = 10_000; // 10 secs
        }

        protected override void DoWork(PeriodicBackgroundWorkerContext workerContext)
        {
            _appStatusService.CheckAppStatus();
        }
    }
}

This worker will call DoWorkAsync() method every 10 seconds while the application is running.

Configuration

Add your BackgroundWorker at OnApplicationInitialization in your module class. The example below initialize the background worker to your module:

using Volo.Abp.BackgroundWorkers;

public class MyModule : AbpModule
{
    public override void OnApplicationInitialization(ApplicationInitializationContext context)
        {
            context.ServiceProvider
                .GetRequiredService<IBackgroundWorkerManager>()
                .Add(
                    context.ServiceProvider.GetRequiredService<AppStatusCheckingWorker>()
                );
        }
}

2.3 KiB Raw Blame History