.NET Core

Using OpenAPI with .NET Core

Using OpenAPI with .NET Core

In this article, we’ll look at using OpenAPI with .NET Core. OpenAPI is a specification for describing RESTful APIs. First, I’ll show you how to use OpenAPI to describe the APIs provided by an ASP.NET Core service. Then, we’ll use the API description to generate a strongly-typed client to use the web service with C#.

Writing OpenAPI descriptions

Developers use the OpenAPI specification to describe RESTful APIs. We can then use OpenAPI descriptions to generate a strongly-typed client library that is capable of accessing the APIs.

Note: Swagger is sometimes used synonymously with OpenAPI. It refers to a widely used toolset for working with the OpenAPI specification.

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How to fix .NET Core’s ‘Unable to obtain lock file access’ error on Red Hat OpenShift

How to fix .NET Core’s ‘Unable to obtain lock file access’ error on Red Hat OpenShift

Well, it finally happened. Despite the added assurances of working with containers and Kubernetes, the old “It works on my machine” scenario reared its ugly head in my .NET Core (C#) code. The image that I created worked fine on my local PC—a Fedora 32 machine—but it crashed when I tried running it in my Red Hat OpenShift cluster.

The error was “Unable to obtain lock file access on /tmp/NuGetScratch.” Let’s take a quick look at what happened, and then I’ll explain how I fixed it.

Identity issues

After a lot of web searching and a discussion with a Red Hat .NET Core engineer, I discovered the underlying problem. It turns out that within a container, the identity used to initially run the program (using the dotnet run command) must be the same for subsequent users.

The problem might be easy to understand, but what’s the solution?

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Tracing .NET Core applications

Tracing .NET Core applications

In this article, we’ll look at different ways of collecting and inspecting events from the .NET Core runtime and base class library (BCL).

EventListener

The EventListener class allows us to get events of the running application. Let’s learn how to use it with an example application. Our application performs an HTTP get and prints the length of the received response.

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CI/CD for .NET Core container applications on Red Hat OpenShift

CI/CD for .NET Core container applications on Red Hat OpenShift

Many people have done continuous integration and continuous delivery (CI/CD) for .NET Core, but they still may wonder how to implement this process in Red Hat OpenShift Container Platform (OCP). The information is out there, but it has not been structurally documented. In this article, we’ll walk through the process.

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