Debugging not working on Insiders build of the Python extension

[luabud]

Environment data

• PTVSD version: debugpy 1.0.0b3
• OS and version: Windows 10
• Python version (& distribution if applicable, e.g. Anaconda): Python 3.7.6 venv
• Using VS Code or Visual Studio: VS Code 1.43.0
• Python Extension version: 2020.4.67731-dev

Actual behavior

Debugging tries to start:

C:\Users\luabud\Apps\MVPSummit2020\tweeterapp> cmd /C "set "DEBUGPY_LAUNCHER_PORT=58504" && set "DEBUGPY_LOG_DIR=c:\Users\luabud\.vscode\extensions\ms-python.python-2020.4.67731-dev" && c:\Users\luabud\Apps\MVPSummit2020\tweeterapp\env\Scripts\python.exe c:\Users\luabud\.vscode\extensions\ms-python.python-2020.4.67731-dev\pythonFiles\lib\python\debugpy\wheels\debugpy\launcher C:\Users\luabud\Apps\MVPSummit2020\tweeterapp\manage.py runserver "

But then it shows this:

And this:

Launch.json file:

{

    "version": "0.2.0",
    "configurations": [
        {
            "name": "Python: Django",
            "type": "python",
            "request": "launch",
            "program": "${workspaceFolder}\\manage.py",
            "args": [
                "runserver",
                "--noreload"
            ],
            "django": true,
            "logToFile": true
        },

    ]
}

Steps to reproduce:

1. On Windows, have a venv selected and try to debug a Django application with the above configuration.

Logs

debugpy.adapter-4500.log
debugpy.launcher-7536.log
debugpy.pydevd.10892.log
debugpy.pydevd.16616.log
debugpy.server-10892.log
debugger.vscode_d61238c6-9c58-4bfe-af6e-3b25496517dc.log

[karthiknadig]

This occurs because debugpyAttach event returns this object:

{
                 "seq": 15,
                 "type": "event",
                 "event": "debugpyAttach",
                 "body": {
                     "name": "Subprocess 16616",
                     "type": "python",
                     "request": "attach",
                     "program": "C:\\Users\\luabud\\Apps\\MVPSummit2020\\tweeterapp\\manage.py",
                     "args": [
                         "runserver"
                     ],
                     "django": true,
                     "logToFile": true,
                     "pythonPath": "c:\\Users\\luabud\\Apps\\MVPSummit2020\\tweeterapp\\env\\Scripts\\python.exe",
                     "cwd": "c:\\Users\\luabud\\Apps\\MVPSummit2020\\tweeterapp",
                     "envFile": "c:\\Users\\luabud\\Apps\\MVPSummit2020\\tweeterapp/.env",
                     "env": {
                         "DJANGO_SETTINGS_MODULE": "tweeter3.settings.development",
                         "PYTHONIOENCODING": "UTF-8",
                         "PYTHONUNBUFFERED": "1"
                     },
                     "stopOnEntry": false,
                     "showReturnValue": true,
                     "console": "integratedTerminal",
                     "internalConsoleOptions": "neverOpen",
                     "debugOptions": [
                         "ShowReturnValue",
                         "Django",
                         "FixFilePathCase"
                     ],
                     "justMyCode": true,
                     "workspaceFolder": "c:\\Users\\luabud\\Apps\\MVPSummit2020\\tweeterapp",
                     "subProcess": true,
                     "__sessionId": "d61238c6-9c58-4bfe-af6e-3b25496517dc",
                     "subProcessId": 16616,
                     "connect": {
                         "host": "127.0.0.1",
                         "port": 58502
                     }
                 }

This should be addressed by #10517 . Using the insiders build after the CI for it completes should address this issue. /cc @int19h

[luabud]

Now I see this on the latest build (2020.4.68060-dev)

debugpy.launcher-19212.log
debugpy.pydevd.8176.log
debugpy.pydevd.21660.log
debugpy.server-8176.log
debugger.vscode_6f7b3c7b-803f-421e-adb3-0637eb93fe6c.log
debugger.vscode_44ca3e86-13f7-47e4-96ba-d8d5d83e1cfd.log
debugpy.adapter-15892.log

[luabud]

FWIW I can only repro this error on VS Code 1.43, not on VS Code Insiders.

[int19h]

I believe it's this code in the extension that's breaking it:

vscode-python/src/client/debugger/extension/configuration/resolvers/attach.ts

Lines 58 to 60 in 6500b2a

	if (!debugConfiguration.host) {
	debugConfiguration.host = 'localhost';
	}

Basically it ends up injecting "host":"localhost" into every attach request if it doesn't have "host" already. Which it doesn't in this case, because it has "connect": {"host": ...}" instead. And then the debugger is complaining that it got both, and it doesn't know which one to use.

But this code should always run, so it's not clear to me why it works sometimes, unless it's just using the old version of debugger in that case. Was it using insiders version of the extension on VSCode 1.43?

[luabud]

Yes, using insiders version of the extension. But I think that's it, it works sometimes. Because now I can't get it to work in VS Code Insiders either 🤷🏽‍♀️

[karthiknadig]

The issue is due to the code @int19h pointed to. This is broken in both VS Code and VS Code Insiders. This has to be addressed for it to work before next release. This does not impact current stable release.

[int19h]

#10600 should have fixed this.