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Python Code Samples

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

136 matches
Database scaling & optimization easy

How to Validate Data Before Scaling in Python

A reusable Python helper that validates required fields and constraint checks on data rows before entering a database pipeline, improving data quality and throughput.

validation data-quality scaling
Python
def validate_data(data, required_fields, constraints=None):
    """
    Basic validation helper demonstrating data-quality workflows
    before scaling (catches bad rows early, improves throughput).
    """
    constraints = constraints or {}

    errors = []
    for field in required_fields:
        if field not in d…
15 0 Open
Database scaling & optimization easy

Monitor Database Index Bloat in Python

Simulates index bloat checks for database tables using random ratio thresholds and reports alerts per index.

database index monitoring
Python
import random
import time

class IndexBloatMonitor:
    def __init__(self, thresholds=(0.5, 0.8, 0.9)):
        self.thresholds = thresholds
        self.indices = {
            "users_pk": 48.2,
            "orders_created_idx": 124.7,
            "products_name_idx": 15.3,
            "payments_user_idx": 203.9,
   …
15 0 Open
Auth & security at scale easy

How to Check Negotiated Cipher Suite in Python

Connect to a TLS server with Python's ssl module and print the negotiated protocol version and cipher suite details.

tls ssl security
Python
import ssl
import socket

def get_cipher_suites(hostname, port=443):
    context = ssl.create_default_context()
    context.set_ciphers("DEFAULT:@SECLEVEL=2")
    
    with socket.create_connection((hostname, port), timeout=5) as sock:
        with context.wrap_socket(sock, server_hostname=hostname) as ssock:
        …
17 0 Open
Auth & security at scale easy

How to Implement an HSTS Preload List Mock in Python

Implements a mock HSTS preload list in Python that supports adding, removing, checking domains with subdomain inheritance, and listing domains.

hsts security domains
Python
import json

class HSTSPreloadList:
    def __init__(self):
        self.domains = {}

    def add_domain(self, domain, include_subdomains=False, max_age=31536000):
        self.domains[domain] = {
            "include_subdomains": include_subdomains,
            "max_age": max_age
        }

    def remove_domain(sel…
15 0 Open
Auth & security at scale easy

How to Revoke Tokens with a Blacklist Set in Python

A minimal TokenBlacklist class using a Python set to revoke, batch-revoke, check, and remove expired tokens for simple token invalidation.

jwt blacklist authentication
Python
import time

class TokenBlacklist:
    def __init__(self):
        self.blacklisted_tokens = set()

    def revoke(self, token):
        self.blacklisted_tokens.add(token)
        print(f"Token {token} revoked. Blacklist size: {len(self.blacklisted_tokens)}")

    def revoke_batch(self, tokens):
        before = len(s…
13 0 Open
Auth & security at scale medium

How to Sign and Verify with Ed25519 in Python

A minimal Ed25519 sign-and-verify helper that generates a key pair, signs a message, and checks the signature with the cryptography library.

ed25519 cryptography signing
Python
import hashlib
from cryptography.hazmat.primitives.asymmetric import ed25519
from cryptography.hazmat.primitives import serialization

def sign_verify_mock(
    message: bytes,
    private_key: ed25519.Ed25519PrivateKey,
    public_key: ed25519.Ed25519PublicKey
) -> tuple[bool, bytes]:
    signature = private_key.sign…
13 0 Open
Production deployment patterns easy

Docker healthcheck CMD mock in Python

Runs a subprocess to curl a health endpoint and returns exit code 0 when healthy, 1 when unhealthy, mimicking a Docker HEALTHCHECK command.

docker healthcheck subprocess
Python
import subprocess
import sys


def run_healthcheck() -> int:
    result = subprocess.run(["curl", "-fsS", "http://localhost:8080/health"], capture_output=True, text=True)
    if result.returncode == 0:
        print("healthy")
        return 0
    print("unhealthy", file=sys.stderr)
    return 1


if __name__ == "__ma…
18 0 Open
Production deployment patterns easy

How to Create a Liveness Probe HTTP Mock in Python

Build a lightweight HTTP server in Python that mimics a Kubernetes-style liveness endpoint, returning JSON health status for local testing.

http healthcheck mock-server
Python
import http.server
import threading
import time


class LivenessHandler(http.server.BaseHTTPRequestHandler):
    def do_GET(self):
        if self.path == "/healthz":
            self.send_response(200)
            self.send_header("Content-Type", "application/json")
            self.end_headers()
            self.wfi…
15 0 Open
Production deployment patterns easy

How to Mock a Dependency for Readiness Probe in Python

Use unittest.mock.Mock to simulate a dependency's readiness check response for testing a service's is_ready method without hitting a real connection.

unittest.mock mock readiness probe
Python
import time
import unittest
from unittest.mock import Mock

class Service:
    def __init__(self, dependency):
        self.dependency = dependency

    def is_ready(self):
        try:
            result = self.dependency.check()
            return result == "ready"
        except Exception:
            return False
…
17 0 Open
Production deployment patterns easy

How to Mock an Ingress TLS Certificate Manager in Python

Build a mock TLS certificate manager for ingress that issues, checks, and renews certificates with expiry tracking — useful for testing deployment workflows before touching real infrastructure.

tls certificates ingress
Python
import ssl
import socket
from datetime import datetime, timedelta


class TLSCertManager:
    def __init__(self, hostname):
        self.hostname = hostname
        self.certificates = {}

    def request_certificate(self, domain, days_valid=90):
        """Mock a certificate issuance request that stores a cert with e…
15 0 Open
Production deployment patterns medium

How to Simulate Blue-Green Deployment Switch in Python

A mock Blue-Green deployment class that deploys new versions to an inactive environment, runs a health check, switches traffic, and supports rollback in Python.

deployment blue-green mock
Python
import random
import time

class BlueGreenDeployment:
    def __init__(self, initial_env="blue"):
        self.environments = {"blue": "v1.0", "green": "v1.0"}
        self.active_env = initial_env
        self.running = True

    def deploy_new_version(self, version, target_env):
        if target_env == self.active_…
16 0 Open
Production deployment patterns medium

How to Smoke Test a Deployment in Python with unittest.mock

Run a post-deploy smoke test by mocking the deployment status check to verify your health-check logic returns PASS/FAIL.

deployment smoke-test unittest-mock
Python
import unittest
from unittest.mock import Mock, patch

class DeploymentService:
    def check_status(self):
        return "unknown"

def smoke_test_deploy():
    service = DeploymentService()
    with patch.object(service, "check_status", return_value="healthy") as mock_check:
        status = service.check_status()
…
13 0 Open
Production deployment patterns easy

How to mock resource request limits in Python

A Python class that simulates CPU and memory limit checks for resource requests, returning clear acceptance or rejection messages.

resource-limits mock class
Python
class ResourceLimits:
    def __init__(self, cpu_limit, memory_limit):
        self.cpu_limit = cpu_limit
        self.memory_limit = memory_limit

    def check_request(self, cpu, memory):
        if cpu > self.cpu_limit:
            return "CPU limit exceeded: {cpu} > {limit}".format(cpu=cpu, limit=self.cpu_limit)
 …
14 0 Open
Production deployment patterns easy

How to simulate a Jenkins pipeline in Python

Simulate a Jenkins-style pipeline in Python by running sequential stages and checking aggregate success.

jenkins pipeline simulation
Python
def run_stage(name, duration, fn):
    print(f"[Pipeline] Running stage: {name}")
    result = fn()
    print(f"[Pipeline] Stage '{name}' completed in {duration}s -> {result}")
    return result

def build_project():
    print("  compiling source...")
    return "BUILD_OK"

def run_tests():
    print("  executing unit…
13 0 Open
Production deployment patterns easy

How to simulate a database migration init container mock in Python

A mock init container that runs environment checks and a staged database migration job before the main application starts, printing progress to stdout.

init-container migration simulation
Python
```python
class MigrationJob:
    def __init__(self, name, steps):
        self.name = name
        self.steps = steps
        self.current_step = 0
        self.status = "pending"

    def run(self):
        print(f"Initializing migration job: {self.name}")
        for step in self.steps:
            self.current_ste…
15 0 Open
Production deployment patterns easy

PodDisruptionBudget minAvailable in Python

Simulate a Kubernetes PodDisruptionBudget check for minAvailable and maxUnavailable constraints with a Python class.

kubernetes pdb simulation
Python
class PodDisruptionBudget:
    def __init__(self, name, min_available=None, max_unavailable=None):
        self.name = name
        self.min_available = min_available
        self.max_unavailable = max_unavailable

    def check_availability(self, ready_pods):
        if self.min_available is not None:
            ret…
12 0 Open

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PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

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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.