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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

5 matches
Errors & debugging medium

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…
13 0 Open
API design & gRPC easy

How to Add a Correlation ID Tracing Header in Python

A mock middleware generates or preserves a correlation ID header and logs structured JSON messages with it for API request tracing.

correlation-id tracing middleware
Python
import uuid
import json
from dataclasses import dataclass, field
from typing import Optional

@dataclass
class Request:
    headers: dict = field(default_factory=dict)

    def get(self, key, default=None):
        return self.headers.get(key, default)

class CorrelationIdMiddleware:
    def __init__(self, header_name…
14 0 Open
API design & gRPC easy

How to Propagate X-Request-ID in Python

Generate a unique request ID when one is missing and pass it through API calls for distributed tracing.

request-id tracing api
Python
import uuid


def generate_request_id() -> str:
    """Generate a unique request ID similar to X-Request-ID header."""
    return str(uuid.uuid4())


def propagate_request_id(request_id: str | None) -> str:
    """Return the request ID for propagation, generating one if missing."""
    if request_id:
        return re…
11 0 Open
Observability & SRE medium

Adding a Correlation ID to Log Context in Python

Injects a correlation ID into the logging context using a context manager and a custom log record factory so every log line includes the ID.

logging correlation-id context-manager
Python
import logging
import uuid
from contextlib import contextmanager

logging.basicConfig(level=logging.INFO, format='%(levelname)s | %(correlation_id)s | %(message)s')


@contextmanager
def correlation_id_context(correlation_id):
    """Temporarily inject a correlation_id into the logging context."""
    extra = {'correl…
15 0 Open
Microservices patterns easy

Correlation ID HTTP header mock in Python

A lightweight HTTP server that echoes or generates correlation IDs to help test distributed systems.

correlation-id http-server mock
Python
import json
import uuid
from http.server import BaseHTTPRequestHandler, HTTPServer


class CorrelationHandler(BaseHTTPRequestHandler):
    CORRELATION_HEADER = "X-Correlation-ID"

    def do_GET(self):
        correlation_id = self.headers.get(self.CORRELATION_HEADER) or str(uuid.uuid4())
        response = {
        …
13 0 Open

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Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.