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Errors & debugging

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

3 matches

How to Mock a Failing Dependency to Test Error Paths in Python

Inject a fake HTTP client that raises a connection error to test how code handles dependency failures without touching the network.

testing mocking requests

Python

import requests

def fetch_user(user_id):
    url = f"https://api.example.com/users/{user_id}"
    response = requests.get(url, timeout=5)
    response.raise_for_status()
    return response.json()

def get_user_name(user_id, http_client):
    try:
        user_data = http_client(user_id)
        return user_data["nam…

16 0 Open

Errors & debugging medium

How to attach a request ID to exception messages in Python

This code shows how to enrich exception messages with contextual request IDs using context variables, making error logs more traceable across concurrent requests.

contextvars exception-handling logging

Python

import logging
from contextvars import ContextVar

request_id_var = ContextVar("request_id", default="unknown")

def add_request_id(exc: Exception) -> Exception:
    exc.args = (f"request_id={request_id_var.get()} | {exc.args[0]}" if exc.args else f"request_id={request_id_var.get()}",) + exc.args[1:]
    return exc

d…

12 0 Open

Errors & debugging easy

Use pprint for Nested Structure Debug Output in Python

Pretty-print nested dictionaries and lists with pprint for readable, organized debug output.

pprint debugging nested-structure

Python

from pprint import pprint

def build_nested_structure():
    """Create a sample nested data structure for demonstration."""
    return {
        "project": "DataPipeline",
        "config": {
            "inputs": ["raw_1.json", "raw_2.json"],
            "processing": {
                "steps": ["clean", "transform",…

15 0 Open

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