Run scheduled background tasks in ASP.NET Core

In the previous blog post called background tasks with ASP.NET Core using the IHostedService Peter described how to use the IHostedInterface for background tasks. In this post, we continue on this subject and add some pointers on how to perform scheduled background tasks.

In many software projects, there are repetitive tasks; some do just repeat every x seconds after the last instance is finished but you might also have to run a task on a schedule like every 10 minutes. When building repeating or scheduled tasks there are many options on how to approach the scheduling and this approach can be influenced by a number of technical choices.

Building the scheduling yourself is an option when you do not want to add extra dependencies to your project, have full control or just want an extra technical challenge. An out of the box solution you can a look at Hangfire, Quartz.net, or an external service that does an http call every x seconds to trigger the task (something like Pingdom).

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Upgrade ASP.NET Core and Entity Framework Core 2.0 to 2.1

In the past weeks we have upgraded our ASP.NET Core 2.0 project to 2.1. The main reason for the upgrade is using the latest signalr capabilities and hosted services. The issues we had are related to the features we use. In our case the upgrade encountered some minor issues. In this blog post I’ll show what we had to change and give some tips on how to upgrade.

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WebHost CreateDefaultBuilder, what differs if you run in Development

Knowing the differences when you run your application in a Development environment

When building ASP.NET Core 2 web applications, most projects are initializing Kestrel with the CreateDefaultBuilder. If you use this extension method to configure Kestrel, it is good to know what is set and what differs when you are running a Development configuration or any other configuration. In practice there are two differences. In this blog I’ll explain the two differences.

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ASP.NET Core background processing with IHostedService

Run background processes with the IHostedService and how to inject your services with dependency injection

Many services need background processing. The ASP.NET Core 2.X IHostedService interface gives you an easy implementation skeleton to implement background processes. The Hosted Services are registered in the dependency injection at startup and started automatically. You do not have to do the pluming to get them started at startup. On shutdown you can implement a graceful shutdown. When running background processes there a few pitfalls to avoid. In this blog I’ll introduce the IHostedService and how to avoid common memory leaks when implementing the hosted service.
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Cannot access a disposed object in ASP.NET Core when injecting DbContext

Find the root cause of what really happened to you disposable object.

Working with ASP.NET core I have seen this error multiple times and can be hard to debug. The error can have multiple root causes. It can be a real pain to find the cause and it is sometimes fixed by only taking care of the symptoms. By finding the root cause, you can take the appropriate action in your code.

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Increase timeout Migrations Entity Framework Core

Use a different connection timeout when running your migrations with EF Core.

Sometimes a migration takes more time then your default timeout of your database connection. In such a case you do want to increase the timeout for the migration to be able to complete, but you do not want to change the timeout for your normal operations.
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Add Index with Include Entity Framework Core

This post explaines how to add index to EF Core with extra columns included from code.

When creating indexes with code first migrations in Entity Framework Core you can create an index on a table by adding the following to your DbContext:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    modelBuilder.Entity<table>() 
        .HasIndex(t =&gt; new { t.Column1, t.Column2}); } 

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