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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

5 matches

How to Log Exceptions with traceback.format_exc in Python

Capture and log a full traceback string when an exception occurs using Python's traceback.format_exc() and logging module.

traceback logging exception

Python

import traceback
import logging

def risky_operation(value):
    return 10 / value

logging.basicConfig(level=logging.ERROR, format='%(asctime)s - %(levelname)s - %(message)s')

def main():
    try:
        result = risky_operation(0)
        print(f"Result: {result}")
    except ZeroDivisionError:
        error_msg =…

14 0 Open

Errors & debugging medium

How to Print an Exception Chain in Python for Debugging

A helper that walks an exception's __cause__ and __context__ chain, printing each level with indentation to make debugging nested errors clearer.

exception-chain debugging traceback

Python

import sys
import traceback

def pretty_exception_chain(exc):
    """Print the full exception chain with cause/context details."""
    chain = []
    current = exc
    seen = set()
    
    while current is not None and id(current) not in seen:
        seen.add(id(current))
        chain.append(current)
        curren…

11 0 Open

Errors & debugging easy

How to Serialize an Exception to a JSON-Safe Dict in Python

Convert any Python exception into a JSON-safe dictionary with type, message, and the last few traceback lines for logging.

exceptions json logging

Python

import json
import traceback
from typing import Any


def exception_to_dict(exc: Exception) -> dict[str, Any]:
    """Convert an exception into a JSON-safe dictionary."""
    return {
        "type": type(exc).__name__,
        "message": str(exc),
        "traceback": traceback.format_exc().strip().split("\n")[-3:],
…

15 0 Open

Errors & debugging easy

How to Use pdb.post_mortem in Python

Automatically enter the Python debugger at the exact point where an uncaught exception occurred, allowing interactive inspection of the crash site.

pdb debugging exceptions

Python

import pdb
import sys

def divide(a, b):
    return a / b

def main():
    try:
        result = divide(10, 0)
        print(f"Result: {result}")
    except Exception:
        # Enter post-mortem debugging when an uncaught exception occurs
        pdb.post_mortem(sys.exc_info()[2])

if __name__ == "__main__":
    main…

13 0 Open

Errors & debugging medium

How to parse a traceback to get the last frame in Python

Extracts the innermost frame's file, line, and function name from a Python traceback object.

traceback exceptions debugging

Python

import sys
import traceback


def parse_traceback_last_frame(exc_info):
    """Return the file, line, and function of the last (innermost) frame."""
    _, _, tb = exc_info
    last_tb = tb
    while last_tb.tb_next is not None:
        last_tb = last_tb.tb_next
    filename = last_tb.tb_frame.f_code.co_filename
    l…

13 0 Open

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