Skip to main content

ASP.NET Core–Running Swagger behind a reverse proxy

Today I helped out a colleague who was struggling with the following use case:

We have an ASP.NET Core Web API with OpenAPI(Swagger) integration enabled. This ASP.NET Core Web API was running behind a reverse proxy(Yarp in case you want to know) and isn’t directly accessibel.

To explain the problem he had, let’s start from the following situation:

When browsing to the Swagger endpoint on https://localhost/proxy/swagger, we got the following:

Do you notice the application url in the address bar vs the url in the Servers dropdown?

If we try to invoke a specific endpoint through the Swagger UI, Swagger tries to do the call directly to http://internalname:5000 which results in 404 error as the service is not available directly on this address.

It seems that Swagger doesn’t respect the Forwarded headers as provided through Yarp.

We fixed it by explicitly reading out the X-Forwarded-Host value and using it to fill up the servers dropdown:

Labels:

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...
Read more

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.
Read more

VS Code Planning mode

After the introduction of Plan mode in Visual Studio , it now also found its way into VS Code. Planning mode, or as I like to call it 'Hannibal mode', extends GitHub Copilot's Agent Mode capabilities to handle larger, multi-step coding tasks with a structured approach. Instead of jumping straight into code generation, Planning mode creates a detailed execution plan. If you want more details, have a look at my previous post . Putting plan mode into action VS Code takes a different approach compared to Visual Studio when using plan mode. Instead of a configuration setting that you can activate but have limited control over, planning is available as a separate chat mode/agent: I like this approach better than how Visual Studio does it as you have explicit control when plan mode is activated. Instead of immediately diving into execution, the plan agent creates a plan and asks some follow up questions: You can further edit the plan by clicking on ‘Open in Editor’: ...
Read more