How to debug asp.net core 3.1 using vscode in linux(ubuntu)

Question

I followed the default steps to

• install .NET Core, (linux-package-manager-ubuntu-1604)
• create and open (ASP.NET core Empty) project in VSCode, (cd ~/projects && dotnet new web -o my-api && cd my-api && code .)
• add vscode tasks.json and launch.json(C# Extension), (ms-dotnettools.csharp)
• add breakpoints(in VSCode),
• and start debugging (press F5 in VSCode).

But this doesn't start the webserver and doesn't stop at breakpoints... It does built the project, as I can see files generated in bin/Debug/netcoreapp3.1/

Running dotnet run inside projects root, builds(restores) and runs the webserver, and I can browse to https://localhost:5001 and http://localhost:5000. But can't debug...

This is the created vscode files

launch.json
{
    // Use IntelliSense to find out which attributes exist for C# debugging
    // Use hover for the description of the existing attributes
    // For further information visit https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md
    "version": "0.2.0",
    "configurations": [
        {
            "name": ".NET Core Launch (web)",
            "type": "coreclr",
            "request": "launch",
            "preLaunchTask": "build",
            // If you have changed target frameworks, make sure to update the program path.
            "program": "${workspaceFolder}/bin/Debug/netcoreapp3.1/my-api.dll",
            "args": [],
            "cwd": "${workspaceFolder}",
            "stopAtEntry": false,
            // Enable launching a web browser when ASP.NET Core starts. For more information: https://aka.ms/VSCode-CS-LaunchJson-WebBrowser
            "serverReadyAction": {
                "action": "openExternally",
                "pattern": "^\\s*Now listening on:\\s+(https?://\\S+)"
            },
            "env": {
                "ASPNETCORE_ENVIRONMENT": "Development"
            },
            "sourceFileMap": {
                "/Views": "${workspaceFolder}/Views"
            }
        },
        {
            "name": ".NET Core Attach",
            "type": "coreclr",
            "request": "attach",
            "processId": "${command:pickProcess}"
        }
    ]
}

tasks.json
{
    "version": "2.0.0",
    "tasks": [
        {
            "label": "build",
            "command": "dotnet",
            "type": "process",
            "args": [
                "build",
                "${workspaceFolder}/my-api.csproj",
                "/property:GenerateFullPaths=true",
                "/consoleloggerparameters:NoSummary"
            ],
            "problemMatcher": "$msCompile"
        },
        {
            "label": "publish",
            "command": "dotnet",
            "type": "process",
            "args": [
                "publish",
                "${workspaceFolder}/my-api.csproj",
                "/property:GenerateFullPaths=true",
                "/consoleloggerparameters:NoSummary"
            ],
            "problemMatcher": "$msCompile"
        },
        {
            "label": "watch",
            "command": "dotnet",
            "type": "process",
            "args": [
                "watch",
                "run",
                "${workspaceFolder}/my-api.csproj",
                "/property:GenerateFullPaths=true",
                "/consoleloggerparameters:NoSummary"
            ],
            "problemMatcher": "$msCompile"
        }
    ]
}

F5 first shows Terminal-tab, then switches to the Debug Console-tab in VSCode

Terminal-tab
> Executing task: dotnet build /home/user/projects/my-api/my-api.csproj /property:GenerateFullPaths=true /consoleloggerparameters:NoSummary <

Microsoft (R) Build Engine version 16.5.0+d4cbfca49 for .NET Core
Copyright (C) Microsoft Corporation. All rights reserved.

  Restore completed in 76,69 ms for /home/user/projects/my-api/my-api.csproj.
  my-api -> /home/user/projects/my-api/bin/Debug/netcoreapp3.1/my-api.dll

Terminal will be reused by tasks, press any key to close it.

Debug Console
-------------------------------------------------------------------
You may only use the Microsoft .NET Core Debugger (vsdbg) with
Visual Studio Code, Visual Studio or Visual Studio for Mac software
to help you develop and test your applications.
-------------------------------------------------------------------

Answer 1

I had the same issue.

First restart the system and see if it gets fixed. Otherwise, try MathieuAuclair's solution then restart the system.

This worked for me.

Answer 2

It seems to be an issue from the installation of VS Code itself, I simply reinstalled VS Code and the issue went away.

sudo snap remove code
sudo snap install code --classic

Although this unsatisfying solution, I have a supposition on why this could have happened.

I installed my modules using the CLI instead of using the GUI. I say that, because I've seen installation log while I was running my web application. I suppose that the installation of the debugger might not have been finished by the time I was running the application. That might have caused a package corruption. But, just uninstalling the extension didn't fix the issue, so I'm not sure that's what happened.

code --install-extension ms-dotnettools.csharp

If reinstalling doesn't work for you, let me know, and also try to change your launch.json, replace openExternally with debugWithChrome. I changed the setting at the same time I reinstalled VS Code.