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Errors & debugging

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

3 matches

How to Add a Correlation ID to Logging Records in Python

Attach a unique correlation ID to every log record using a custom logging.Filter, making distributed request tracking traceable.

logging correlation-id filter

Python

import logging
import uuid
from dataclasses import dataclass, field


@dataclass
class CorrelationIdFilter(logging.Filter):
    correlation_id: str = field(default_factory=lambda: str(uuid.uuid4()))

    def filter(self, record: logging.LogRecord) -> bool:
        record.correlation_id = self.correlation_id
        re…

15 0 Open

Errors & debugging medium

Implement circuit breaker open after failures demo in Python

A minimal CircuitBreaker class that calls a function and automatically 'opens' after a set number of consecutive failures, blocking further calls with a RuntimeError.

circuit-breaker resilience error-handling

Python

import time
from datetime import datetime


class CircuitBreaker:
    def __init__(self, threshold=3):
        self.threshold = threshold
        self.failure_count = 0
        self.is_open = False

    def call(self, func, *args, **kwargs):
        if self.is_open:
            raise RuntimeError("Circuit is OPEN")
  …

13 0 Open

Errors & debugging medium

Redact secrets from log message formatter in Python

Build a custom logging.Formatter that masks passwords, API keys, and credit card numbers in log output.

logging redaction security

Python

import re
import logging

class RedactingFormatter(logging.Formatter):
    """Formatter that masks sensitive data in log messages."""
    
    SENSITIVE_PATTERNS = [
        (re.compile(r'password[=:]\s*\S+', re.IGNORECASE), 'password=[REDACTED]'),
        (re.compile(r'api[_-]?key[=:]\s*\S+', re.IGNORECASE), 'api_key…

14 0 Open

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