Hosting background services

The IHostedService interface defines a contract for a background task. By implementing this interface in a concrete class, we can spawn workers in the background of our app and we don't interfere with it. These services have the life cycle of the ASP.NET app.

There is a special template in Visual Studio for creating a worker service:

This is a special kind of project that you can't use for serving web content. If you are curious, it uses the following declaration:

<ProjectSdk="Microsoft.NET.Sdk.Worker">

ASP.NET Core offers a convenience class, BackgroundService, from which you can inherit, instead of implementing IHostedService:

public class BackgroundHostedService : BackgroundService
{
    protected override Task ExecuteAsync(CancellationToken 
    cancellationToken)
    {
        while (!cancellationToken.IsCancellationRequested)
        {
            //do something...