Reference library

Python Code Samples

Medium snippets you can copy, study, and run in the browser editor.

6 matches
Files & data medium

How to Audit Environment Variable Files for Missing Values in Python

A Python tool that reads an environment variable file and reports any variables with empty or missing values.

environment-variables file-audit configuration
Python
import os
import re
from pathlib import Path

def audit_env_file(filepath: str) -> None:
    """
    Audit an environment variable file for missing values.
    Prints file status and lists variables that have empty values.
    """
    path = Path(filepath)
    if not path.exists():
        print(f"Error: File '{filepa…
40 0 Open
Testing & modern typing medium

How to Run an Integration Test with Docker Compose Mock in Python

Run a Python integration test against a docker-compose environment, using mocks to simulate service health and business logic responses.

docker integration-testing mocking
Python
import subprocess
import json
from typing import Dict

def run_integration_test() -> Dict[str, str]:
    """
    Simulates an integration test against a docker-compose environment
    using a mock service that returns canned responses.
    """
    # Mock docker-compose environment check
    env_ready = subprocess.run(…
15 0 Open
Auth & security at scale medium

How to Mock Environment Variables in Python

A context manager that injects and restores environment variables for isolated testing of config-dependent code.

env vars context manager testing
Python
import os

class EnvInjector:
    def __init__(self, mock_vars=None):
        self.mock_vars = mock_vars or {}
        self.original = {}

    def __enter__(self):
        for key, value in self.mock_vars.items():
            if key in os.environ:
                self.original[key] = os.environ[key]
            os.env…
14 0 Open
Auth & security at scale medium

How to Mock Environment Variables in Python for 12-Factor Config

Read 12-factor config from env vars and test/mock them with unittest.mock.patch.dict without touching the real environment.

environment-variables 12-factor testing
Python
import os
import json
from unittest.mock import patch

def load_config(env_prefix="APP"):
    """Read 12-factor style config from env vars"""
    required = ["DATABASE_URL", "API_KEY"]
    optional = {"PORT": "8080", "DEBUG": "false"}
    
    config = {}
    for key in required:
        full_key = f"{env_prefix}_{key…
13 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

Mock ConfigMap Mount Environment Variables in Python

Simulate reading environment variables from a Kubernetes ConfigMap-mounted directory and test it with mocks.

kubernetes configmap mocking
Python
import os
import tempfile
from unittest.mock import patch

def load_config_from_mount(mount_path):
    """Simulate reading environment variables from a ConfigMap-mounted directory."""
    config = {}
    for filename in os.listdir(mount_path):
        file_path = os.path.join(mount_path, filename)
        if os.path.i…
14 0 Open

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Guide: free Python code samples library

Copy-ready Python snippets for learners and developers

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.

How to use this library

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  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

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.