pythonvisual-studio-codevscode-debugger

How can I debug Python console_script command line apps with the VSCode debugger?


I've a Python package package_name which provides a command line application command-line-app-name as console_script:

setup.py:

setup(
    ...
    entry_points={"console_scripts": ["command-line-app-name=package_name.cli:main"]},
    ...
)

The virtualenv is located in <project>/.venv and managed with pipenv. pipenv managed venvs should support VSCode debugging integration. I've created a debugger configuration launch.json file with setting the Python path to the venv (pythonPath):

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Python: command-line-app-name",
            "type": "python",
            "request": "launch",
            "stopOnEntry": false,
            "program": "command-line-app-name",
            "linux": {
                "pythonPath": "${workspaceFolder}/.venv/bin/python",
                "args": ["-r", "/home/florian/gitlab/package_name/data/Test_MRM.d"]
            },
            "windows": {
                "pythonPath": "${workspaceFolder}/.venv/Scripts/python.exe",
                "args": ["-r", "D:\\MassHunter\\Data\\demo_0000.d"],
            },
            "console": "integratedTerminal"
        }
    ]
}

The Windows and Linux specific venv python executable and command line arguments should not have an impact. If I run the debugger I get: FileNotFoundError: [Errno 2] No such file or directory: '/home/florian/gitlab/package-name/command-line-app-name'. It seems like I'm miss-interpreting the documentation somehow. I tried to find help w.r.t. vscode-python as well as debugpy without success. How can I debug a console script command line app (instead of a package module)?


Solution

  • console_scripts cannot be debugged out-of-the-box. The solution is to call the entry point function directly instead ("program": "${workspaceRoot}/package_name/cli.py",). This requires to add the if __name__ == '__main__': idiom in the corresponding module (here: cli.py). In my case the command line argument parser used is click. However the pseudo-code should be very similar for other command line parser libs.

    package_name/cli.py:

    @click.command()
    @click.option(...)
    def main(<args>, <kwargs>):
        ...
    
    
    if __name__ == '__main__':
        main()  # pylint: disable=no-value-for-parameter
    
    

    .vscode/launch.json:

    {
        // Use IntelliSense to learn about possible attributes.
        // Hover to view descriptions of existing attributes.
        // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
        "version": "0.2.0",
        "configurations": [
            {
                "name": "Python: command-line-app-name",
                "type": "python",
                "request": "launch",
                "stopOnEntry": false,
                "program": "${workspaceRoot}/package_name/cli.py",
                "linux": {
                    "pythonPath": "${workspaceFolder}/.venv/bin/python",
                    "args": ["-r", "/home/florian/gitlab/package_name/data/Test_MRM.d"]
                },
                "windows": {
                    "pythonPath": "${workspaceFolder}/.venv/Scripts/python.exe",
                    "args": ["-r", "D:\\MassHunter\\Data\\demo_0000.d"],
                },
                "console": "integratedTerminal"
            }
        ]
    }
    

    NOTE: The tool used to manage the venv makes a difference. This solution does work in case the venv is managed with pipenv. The solution does not work in case the venv is managed with poetry.