Skip to main content

.NET Aspire error - Aspire.Hosting.DistributedApplicationException: 'Failed to get effective launch profile for project resource ''.

I’m currently working on 'Aspirifying' (don't know if that is a correct verb' multiple applications. After enabling Aspire for one application, the Aspire Host failed to launch with the following error message:

Aspire.Hosting.DistributedApplicationException: 'Failed to get effective launch profile for project resource ''. There is malformed JSON in the project's launch settings file at 'C:\projects\<ProjectName>\Properties\launchSettings.json'.'

The inner exception gave some extra details:

JsonException: The JSON value could not be converted to System.Nullable`1[System.Boolean]. Path: $.profiles[‘<ProjectName>.API'].dotnetRunMessages | LineNumber: 21 | BytePositionInLine: 33.

I opened up the mentioned launchSettings.json file:

The culprit is the dotnetRunMessages setting where instead of a 'true' string, we should specify a boolean value:

No idea where this setting is coming from, but I certainly never set its value myself. So, I assume that the json structure has changed over time.

Sidenote: What does dotnetRunMessages do?

The dotnetRunMessages property in the launchSettings.json file is used to control whether messages are displayed when running a .NET application using the dotnet run command. This setting provides immediate feedback upon running the application, which can be particularly useful during development.

When set to true, it ensures that messages are displayed in the terminal immediately after running the dotnet run or dotnet watch commands. This should help us understand what is happening during the startup process and can prevent confusion if there is a delay before any output is shown.

It can also make the console output more verbose, providing additional details about the application's execution. This can be beneficial when using tools like dotnet watch inside Visual Studio, as it gives more context about what is happening.

More information

Enabling .NET Aspire for an existing solution

.NET Aspire and launch profiles - .NET Aspire | Microsoft Learn

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