Python Code
Samples
Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.
How to Build a Mock Route53 DNS API in Python
Create a mock DNS API server in Python that simulates Route53 record lookups and updates using the standard library.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs
class DNSUpdateHandler(BaseHTTPRequestHandler):
records = {"example.com": "1.2.3.4"}
def do_GET(self):
domain = parse_qs(urlparse(self.path).query).get("domain", [""])[0]
if dom…How to Create a Mock Docker Registry Auth Token Server in Python
Build a mock Docker Registry token authentication server that issues signed JWT-like tokens for push and pull access using Python's standard library.
import base64
import hashlib
import hmac
import json
import time
from http.server import BaseHTTPRequestHandler, HTTPServer
class TokenAuthHandler(BaseHTTPRequestHandler):
"""Mock Docker Registry token authentication server."""
SECRET_KEY = b"mock-secret-key"
def generate_token(self, username: str, pas…How to Build a Branch Protection Audit Mock API in Python
A mock HTTP API that serves branch protection rules for repositories and audits them for compliance, built with Python's standard library.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs
REPOSITORIES = {
"alpha": {
"default_branch": "main",
"branches": ["main", "develop", "feature-x"],
"protection_rules": {
"main": {"required_reviews": 2, "dismiss_…Build a BFF (Backend for Frontend) Mock Aggregator in Python
A minimal HTTP server implementing the BFF pattern that aggregates user data and orders from two mock backends into a single JSON response.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse
class MockBackendA:
def get_user(self, user_id):
return {"id": user_id, "name": "Alice", "service": "backend-a"}
class MockBackendB:
def get_orders(self, user_id):
return [
{…Build a Bulk Array POST Mock Server in Python
Creates an HTTP mock server that accepts POST requests with a JSON array and returns incremental IDs for each item.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse
class MockHandler(BaseHTTPRequestHandler):
def do_POST(self):
if urlparse(self.path).path != "/bulk":
self.send_response(404)
self.end_headers()
return
cont…Build a Mock REST API with PUT and GET in Python
A minimal mock REST server implementing idempotent PUT for resource replacement and GET for retrieval, built with Python's http.server module.
from http.server import BaseHTTPRequestHandler, HTTPServer
import json
from urllib.parse import urlparse
mock_db = {}
class MockAPIHandler(BaseHTTPRequestHandler):
def do_PUT(self):
parsed = urlparse(self.path)
resource_id = parsed.path.strip("/").split("/")[-1]
content_length = int(self.…How to Build a Batch Operations Multi-Status 207 Mock Server in Python
Build a mock HTTP server that accepts a batch of operations and returns HTTP 207 Multi-Status with per-operation status codes in JSON.
from http.server import BaseHTTPRequestHandler, HTTPServer
import json
class BatchHandler(BaseHTTPRequestHandler):
def do_POST(self):
if self.path != "/batch":
self.send_response(404)
self.end_headers()
return
content_length = int(self.headers.get("Content-Leng…How to Build a Mock REST GET Endpoint Handler in Python
Create a lightweight mock REST GET server in Python using the standard library, with a dict-based route registry that maps paths to handler functions and returns JSON responses with proper HTTP status codes.
from http.server import BaseHTTPRequestHandler, HTTPServer
import json
# Mock API handler registry
def handle_users():
return {"status": "ok", "data": [{"id": 1, "name": "Alice"}, {"id": 2, "name": "Bob"}]}
def handle_products():
return {"status": "ok", "data": [{"id": 101, "name": "Laptop", "price": 999.99}…How to Build an Idempotency-Key POST Handler in Python
Python HTTP server mock that accepts POST requests and deduplicates them using an Idempotency-Key header, returning the same response for repeated calls.
import hashlib
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse
class MockAPI(BaseHTTPRequestHandler):
responses = {}
def do_POST(self):
length = int(self.headers.get("Content-Length", 0))
body = self.rfile.read(length).decode("utf-8")
…How to Implement Content Negotiation with JSON and XML in Python
Build an HTTP server that returns JSON or XML responses based on the client's Accept header, with a 406 response for unsupported formats.
import json
import xml.etree.ElementTree as ET
from http.server import BaseHTTPRequestHandler, HTTPServer
class RequestHandler(BaseHTTPRequestHandler):
def do_GET(self):
data = {"message": "Hello, world!"}
accept_header = self.headers.get("Accept", "")
if "application/json" in accept_hea…How to Implement a REST DELETE Mock Server Returning 204 in Python
A minimal HTTP server mock that responds to DELETE requests with 204, 404, or 403 statuses based on the resource ID.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
class MockHandler(BaseHTTPRequestHandler):
def do_DELETE(self):
if self.path.startswith("/api/resource/"):
resource_id = self.path.split("/")[-1]
if resource_id == "42":
# Successful delete: 204 …How to Mock a Webhook Subscribe Callback URL in Python
Mock a webhook subscribe callback URL using Python's http.server to receive and parse POST requests sent by webhook providers.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
class WebhookHandler(BaseHTTPRequestHandler):
def do_POST(self):
content_length = int(self.headers.get('Content-Length', 0))
payload = json.loads(self.rfile.read(content_length)) if content_length else {}
print…Serve Swagger UI with Python's built-in HTTP server
Hosts a self-contained Swagger UI with a mock OpenAPI spec using only Python's standard library HTTP server.
from http.server import HTTPServer, SimpleHTTPRequestHandler
import os
import tempfile
SWAGGER_HTML = """<!DOCTYPE html>
<html>
<head>
<title>Mock Swagger UI</title>
<link rel="stylesheet" href="https://unpkg.com/swagger-ui-dist@4/swagger-ui.css">
</head>
<body>
<div id="swagger-ui"></div>
<script src…Version API by Accept Header with Vendor Media Types in Python
Build a mock HTTP server that routes to API versions by parsing vendor-specific Accept headers in Python.
from http.client import HTTPMessage
from http.server import BaseHTTPRequestHandler, HTTPServer
class VendorVersionHandler(BaseHTTPRequestHandler):
def do_GET(self):
accept = self.headers.get("Accept", "")
version = "v1"
if "application/vnd.myapi.v2+json" in accept:
version = "…How to Check Uptime with a Synthetic HTTP Mock in Python
Run a mock HTTP server locally and probe it with urllib to measure synthetic uptime and response times, perfect for testing monitoring logic without external dependencies.
import http.server
import threading
import time
import urllib.request
class MockHandler(http.server.BaseHTTPRequestHandler):
def do_GET(self):
if self.path == "/health":
self.send_response(200)
self.send_header("Content-Type", "application/json")
self.end_headers()
…Correlation ID HTTP header mock in Python
A lightweight HTTP server that echoes or generates correlation IDs to help test distributed systems.
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 = {
…How to Build an OAuth Client Credentials Mock Server in Python
A minimal HTTP mock server implementing the OAuth 2.0 client credentials grant for local testing and microservice development.
from http.server import HTTPServer, BaseHTTPRequestHandler
import json
TOKENS = {"valid_token": "demo_access_token", "client_id": "my_service"}
class OAuthHandler(BaseHTTPRequestHandler):
def do_POST(self):
if self.path == "/oauth/token":
length = int(self.headers.get("Content-Length", 0))
…How to Mock Service Versioning URI in Python
Run a minimal HTTP server in Python that routes requests to different versions of a service URI like /v1/users vs /v2/users.
from http.server import HTTPServer, BaseHTTPRequestHandler
import json
class VersionedHandler(BaseHTTPRequestHandler):
def _send_json(self, payload, status=200):
body = json.dumps(payload).encode("utf-8")
self.send_response(status)
self.send_header("Content-Type", "application/json")
…How to Mock an Ambassador Edge Proxy in Python
Build a lightweight mock Ambassador edge proxy with Python's http.server that responds to health and user endpoint requests for local development and testing.
import http.server
import json
import urllib.parse
import threading
class AmbassadorProxyHandler(http.server.BaseHTTPRequestHandler):
def do_GET(self):
parsed = urllib.parse.urlparse(self.path)
if parsed.path == "/health":
self.send_response(200)
self.send_header("Content-T…ACME LetsEncrypt Mock Challenge Server in Python
A minimal HTTP server that serves key authorizations for ACME/Let's Encrypt DNS-01 or HTTP-01 challenges during testing and validation.
from http.server import HTTPServer, BaseHTTPRequestHandler
import json
# In-memory store simulating the ACME challenge token -> key authorization pair
challenge_store = {
"token_example": "token_example.key_authorization"
}
class AcmeChallengeHandler(BaseHTTPRequestHandler):
def do_GET(self):
# Extra…How to Mock a Content Security Policy Header in Python
Mock a Content-Security-Policy header locally and verify it's served correctly using Python's built-in HTTP server.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
CSP_HEADER = "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'"
class MockServer(BaseHTTPRequestHandler):
def do_GET(self):
if self.path == "/":
self.send_response(200)
self.send_header("…OAuth2 authorization code flow mock in Python
A minimal HTTP server that mocks the OAuth2 authorization code flow, issuing codes via /authorize and exchanging them for tokens at /token.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs
AUTH_CODE_STORE = {}
CLIENT_ID = "demo-client"
REDIRECT_URI = "http://localhost:8000/callback"
class OAuthHandler(BaseHTTPRequestHandler):
def do_GET(self):
parsed = urlparse(self.path)
…Browse by section
Each section groups closely related Python snippets.
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
- Pick a topic section — strings, lists, files, functions, and more
- Open a sample, read How it works, and copy the code block
- 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.