ASP.NET Core Configuration - System.ArgumentException: Item has already been added.

In ASP.NET Core you can specify an environment by setting the 'ASPNETCORE_ENVIRONMENT' environment variable on your server. Yesterday however I wanted to setup a second environment on the same machine. To achieve this I added a second website to IIS and set the environment variable through a parameter in my web.config:

Unfortunately after doing that my application no longer worked. In the Event Viewer I could see the following error message:

Application: dotnet.exe

CoreCLR Version: 4.6.26628.5

Description: The process was terminated due to an unhandled exception.

Exception Info: System.ArgumentException: Item has already been added. Key in dictionary: 'ASPNETCORE_ENVIRONMENT' Key being added: 'ASPNETCORE_ENVIRONMENT'

   at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add)

   at System.Environment.ToHashtable(IEnumerable`1 pairs)

   at System.Environment.GetEnvironmentVariables()

   at Microsoft.Extensions.Configuration.EnvironmentVariables.EnvironmentVariablesConfigurationProvider.Load()

   at Microsoft.Extensions.Configuration.ConfigurationRoot..ctor(IList`1 providers)

   at Microsoft.Extensions.Configuration.ConfigurationBuilder.Build()

   at Microsoft.AspNetCore.Hosting.WebHostBuilder..ctor()

   at Web.Program.Main(String[] args) in c:\Program.cs:line 10

It seems that ASP.NET Core doesn’t like that you try to set the same variable twice. Strange because I thought it worked on a previous version of .NET Core(I’m running on 2.1at the moment).

To fix it, I had to remove the environment variable from the system(restart the system) and set the environment for all applications through the web.config.

Anyone with a better solution?

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 ...

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.

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’: ...

The art of simplicity

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