Hosting services in .NET Core console application

When building services for data processing you do not always need a user interface. An IHost is very capable of hosting such an application in a console application as headless service. The IHost does give you a number of advantages like graceful shut down, dependency injection, logging, and configuration. When running long processing tasks in Docker containers, graceful shut down helps you to keep the state of your application consistent. This post explains how making use of the generic IHost in .NET Core for headless services.

Advertisement

HttpClient and HttpClientFactory in ASP.NET Core

With .NET Core 2.1 the HttpClientFactory is introduced. The HttpClientFactory is a factory class which helps with managing HttpClient instances. Managing your own HttpClient correctly was not so easy. The HttpClientFactory gives you a number of options for easy management of your HttpClient instances. In this post I’ll explain how to use the HttpClientFactory in your ASP.NET Core application.

.NET Core, what is my OS

There are a few cases where it is very useful to know the OS your .NET Core application is running on. One of those cases is when you need to set a time zone. Each OS does have its own naming of time zones. You can just try and catch the exception and then retry for another OS, however, if you know the OS, then it is far nicer to do this without exception handling.

Access XML SOAP services in .NET Core and client certificates (SSL)

Only a few years back Windows Communication Foundation (WCF) was the way to do communication on the Microsoft platform based on SOAP protocol. Now a days new services are mostly build on top of Representational State Transfer (REST) Services. Sometimes you have to access a ‘legacy’ SOAP services for .NET Core. .NET Core has limited WCF support. In this blog post I’ll explain how to consume SOAP services form .NET Core.

ASP.NET Core background processing with IHostedService

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.

Increase timeout Migrations Entity Framework 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.

Add Index with Include Entity Framework Core

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}); } 

Implement Pessimistic Concurrency in Entity Framework Core

In a scenario where we were using SQL server as a queue, before publishing events to external queues, we wanted the data to be processed only once and in order, even with multiple processors for failover. When reading from the table we wanted to lock the records and block other processors from reading those records, while being processed. This is called Pessimistic Concurrency, unfortunately Entity Framework Core does not support this out of the box. To realize Pessimistic Concurrency you need to write your own SQL queries directly on the database (The solution is database type bound, in this case Microsoft SQL server). This blog post will show how it can be accomplished.

Make a .NET Core CLI Extensions

.NET Core comes with a new tool chain for software development. These tools run from the CLI (Command Line Interface). Out of the box you have command line restore, build, etc. These tools are the primary tools on which higher-level tools, such as Integrated Development Environments (IDEs), editors and build orchestrators can build on. The tools set in extendable on project level. That means that you can add tools in the context of your project by adding it to your project file. The tool you want to run with the from the CLI is called a verb (dotnet-verb). Running a verb is done by: dotnet verb.