Logging messages to file in Python not working when running outside interactive mode in VS Code

Question

I have a simple Python code that logs messages to a file using the logging module. However, when I run this code in Visual Studio Code (VS Code) outside of the interactive mode, I do not see any logs in the file. Strangely, when I run the same code in the interactive mode, the logs are successfully written to the file. Here is my code:

import logging

# Configure logger for use case 1
logger1 = logging.getLogger('use_case_1')
logger1.setLevel(logging.INFO)

# Create file handler for use case 1
handler1 = logging.FileHandler('./use_case_1.log', 'a')
formatter1 = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
handler1.setFormatter(formatter1)
logger1.addHandler(handler1)

# Create stream handler for use case 1 (console)
console_handler1 = logging.StreamHandler()
console_handler1.setFormatter(formatter1)
logger1.addHandler(console_handler1)

# Usage example
logger1.info('Log message for use case 1')
handler1.flush()  # Flush the file handler

I would like to understand the difference between running the code in VS Code outside the interactive mode versus running it in the interactive mode, and why I am not getting any logs when running outside of the interactive mode. Any insights or suggestions would be greatly appreciated.

Answer 1

You're using relative paths, so the file location will depend on the cwd of the intepreter process. You could switch to absolute paths, or configure VS Code to have a consistent cwd for the different types of Python processes.

• For Jupyter, use the jupyter.notebookFileRoot setting, which defaults to "${fileDirname}".

• For the run file action and corresponding button, use the python.terminal.executeInFileDir setting, which toggles whether the cwd is the file directory or the workspace directory.

• For tasks, use the "options" property's "cwd" property.

See also https://code.visualstudio.com/docs/editor/variables-reference.