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How to mock a REST POST endpoint in Python
Create a simple mock REST server that responds to POST requests with a 201 status and a JSON body.
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
class MockHandler(BaseHTTPRequestHandler):
def do_POST(self):
content_length = int(self.headers.get("Content-Length", 0))
body = self.rfile.read(content_length) if content_length else b"{}"
try:
data = json…Return Proper HTTP Status Codes Table in Python
Mock HTTP status code table with proper numeric and textual representations, including formatted status lines and a filtered table view.
# Mock HTTP status code table with proper numeric and textual representations
codes = {
200: "OK",
201: "Created",
204: "No Content",
301: "Moved Permanently",
302: "Found",
304: "Not Modified",
400: "Bad Request",
401: "Unauthorized",
403: "Forbidden",
404: "Not Found",
50…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…How to Mock a Timeout per HTTP Request in Python
Simulate a per-request HTTP timeout using unittest.mock to test timeout handling without network access.
import time
from unittest.mock import Mock, patch
# Simulate an HTTP client that might time out
def fetch_data(url, timeout=5):
time.sleep(0.5) # Simulate network delay
return f"Response from {url}"
# Mock to test timeout behavior without real network
def test_timeout():
mock_response = Mock(side_effect…How to Generate and Propagate W3C Trace Context Headers in Python
Generate and propagate W3C traceparent and tracestate headers for distributed tracing in Python, with mock service headers.
import uuid
def generate_w3c_traceparent(trace_id=None, parent_id=None, flags="01"):
if trace_id is None:
trace_id = uuid.uuid4().hex[:32]
if parent_id is None:
parent_id = uuid.uuid4().hex[:16]
return f"00-{trace_id}-{parent_id}-{flags}"
def create_mock_headers(service_name, trace_id=N…How to Mock HTTP Client Latency in Python
Simulate outbound HTTP request latency with configurable ranges to test timeouts, retries, and SLO monitoring without external services.
import time
import random
def mock_latency(host: str, min_ms: int = 100, max_ms: int = 500) -> dict:
"""Simulate an outbound HTTP request with mock latency."""
latency_ms = random.randint(min_ms, max_ms)
start = time.perf_counter()
time.sleep(latency_ms / 1000)
elapsed_ms = (time.perf_counter() - …How to Mock an OTLP HTTP Endpoint in Python
This code implements a lightweight HTTP server that accepts OTLP/HTTP trace exports, stores spans by trace ID, and exposes them via a simple GET endpoint for debugging.
import json
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
from collections import defaultdict
class TraceHandler(BaseHTTPRequestHandler):
traces = defaultdict(list)
def do_POST(self):
if self.path == "/v1/traces":
length = int(self.headers.get("Content-Length", 0))
…How to Ship Logs to an Aggregator Endpoint in Python
Ship batched log entries to a mock HTTP aggregator endpoint with proper error handling and response status.
import json
import requests
from datetime import datetime, timezone
LOG_ENTRIES = [
{"timestamp": "2024-01-15T10:00:00Z", "level": "INFO", "message": "Server started"},
{"timestamp": "2024-01-15T10:00:05Z", "level": "WARN", "message": "High memory usage"},
{"timestamp": "2024-01-15T10:00:10Z", "level": "E…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 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 API Gateway Router in Python
Create a lightweight HTTP server that routes requests to mock microservice responses, simulating an API gateway for local development and testing.
from http.server import HTTPServer, BaseHTTPRequestHandler
import json
class SimpleGateway(BaseHTTPRequestHandler):
def do_GET(self):
routes = {
"/users": {"service": "user-service", "status": "ok", "count": 42},
"/orders": {"service": "order-service", "status": "ok", "count": 17}…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…Retry idempotent GET requests in Python
A Python function that retries an idempotent GET request a fixed number of times with a delay between attempts, raising a RuntimeError only after all retries fail.
import time
import urllib.error
import urllib.request
from http.client import HTTPException
def fetch_with_retry(url, max_retries=3, delay=1.0):
for attempt in range(1, max_retries + 1):
try:
with urllib.request.urlopen(url, timeout=5) as response:
return response.read().decode…How to Create Secure Session Cookies in Python with Secure, HttpOnly, and SameSite Flags
This code demonstrates how to create a secure session cookie using Python's stdlib, setting Secure, HttpOnly, and SameSite attributes to protect against common web vulnerabilities.
import http.cookies
import secrets
class SessionManager:
def __init__(self):
self.cookie = http.cookies.SimpleCookie()
def create_session_cookie(self, session_id=None):
session_id = session_id or secrets.token_hex(16)
self.cookie["session"] = session_id
self.cookie["session"][…How to Enforce a Strict Referrer Policy in Python
Validate HTTP headers to enforce a strict same-origin Referrer policy, accepting only origin-only URLs or absent Referer values.
import re
from unittest.mock import patch
def strict_referrer_policy(headers):
"""Return True if Referer header is absent or strictly same-origin."""
referer = headers.get("Referer")
if referer is None:
return True
# Strict-Origin-When-Cross-Origin allows same-origin full URL
# but here we…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("…How to Set a SameSite Cookie in Python
Set a SameSite cookie attribute in Python using the standard library's SimpleCookie class.
from http.cookies import SimpleCookie
def set_same_site_cookie(name, value, same_site="Lax"):
cookie = SimpleCookie()
cookie[name] = value
cookie[name]["path"] = "/"
cookie[name]["samesite"] = same_site
return cookie[name].OutputString()
if __name__ == "__main__":
print(set_same_site_cookie("…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.
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…Browse by section
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