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How to Mock Time for Cache TTL Testing in Python
This code demonstrates how to test a cache's TTL expiration logic by mocking time.time with unittest.mock to control the passage of time.
import time
from unittest.mock import patch
class ConfigCache:
def __init__(self, ttl=60):
self.ttl = ttl
self._store = {}
self._timestamps = {}
def get(self, key):
if key not in self._store:
return None
if time.time() - self._timestamps[key] > self.ttl:
…
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.
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…
How to Mock HTTP Responses to Verify HSTS Headers in Python
This code demonstrates how to use unittest.mock to intercept and capture HTTP response headers, specifically the Strict-Transport-Security header, from a mocked HTTPServer handler for security validation.
from http.server import BaseHTTPRequestHandler, HTTPServer
from unittest.mock import patch
class StrictTransportMock(BaseHTTPRequestHandler):
def do_GET(self):
self.send_response(200)
self.send_header("Strict-Transport-Security", "max-age=31536000; includeSubDomains")
self.end_headers()
…
How to Mock Kubernetes Secret Mounts in Python
Create and inspect a mock Kubernetes secret volume mount using the official client library and unittest.mock.
import json
from kubernetes import client, config, watch
from unittest.mock import Mock, patch
def create_mock_mount_spec():
"""Create a mock Kubernetes secret volume mount."""
mock_client = Mock()
mock_client.api_version = "v1"
mock_client.kind = "Secret"
mock_client.metadata = {"name": "my-secre…
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.
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()
…
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