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How to Monitor Website Content Changes in Python
This script fetches a webpage's content, computes its SHA-256 hash, and compares it with the last stored hash to detect and alert on changes.
import time
import hashlib
import requests
from pathlib import Path
def fetch_content_hash(url: str) -> str:
response = requests.get(url, timeout=10)
response.raise_for_status()
return hashlib.sha256(response.text.encode()).hexdigest()
def monitor_website(url: str, check_interval: int = 60):
hash_fil…How to Ping Multiple Hosts in Parallel with Python ThreadPoolExecutor
A parallel host-pinging script using ThreadPoolExecutor and subprocess to check connectivity across multiple addresses concurrently.
import subprocess
from concurrent.futures import ThreadPoolExecutor
from pathlib import Path
HOSTS = [
"google.com",
"github.com",
"stackoverflow.com",
"nonexistent.invalid",
"localhost",
]
def ping_host(host: str) -> str:
"""Ping a single host and return a status string."""
result = subp…How to Run Tesseract OCR from Python with subprocess
This script uses Python's subprocess module to invoke the Tesseract OCR engine from the command line and return the extracted text.
import subprocess
def ocr_image(image_path):
command = ["tesseract", image_path, "stdout"]
result = subprocess.run(command, capture_output=True, text=True)
return result.stdout.strip()
if __name__ == "__main__":
# Stub: call the actual tesseract (must be installed)
text = ocr_image("sample.png")
…How to Scan Configuration Files for Security Issues in Python
Automatically scan configuration files for common security mistakes using regex rules in Python.
import re
import os
from pathlib import Path
SECURITY_RULES = [
(r'^#\s*INSECURE_', 'Insecure comment starts with # INSECURE_'),
(r'password\s*=\s*("|\\\')?[^"\\\'"\s]+("|\\\')?$', 'Hardcoded password'),
(r'debug\s*=\s*True', 'Debug mode enabled'),
(r'[Pp]ermit[Rr]ootLogin\s+yes', 'PermitRootLogin ena…How to Scan Open Ports on a Host with Python
A Python function that uses socket.connect_ex to check for open TCP ports on a given host within a range and returns a list of open ports.
import socket
def scan_ports(host, start_port, end_port):
open_ports = []
for port in range(start_port, end_port + 1):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(0.5)
result = sock.connect_ex((host, port))
if result == 0:
open_ports.app…How to Send an Email with smtplib and a Mock Server in Python
Send an email using smtplib and verify it with a local aiosmtpd mock SMTP server — perfect for testing without a real mail server.
import smtplib
from email.message import EmailMessage
import aiosmtpd.controller as controller
import threading
def handle_message(server, session, envelope):
print(f"Mock server received message:")
print(f"From: {envelope.mail_from}")
print(f"To: {envelope.rcpt_tos}")
print(f"Subject: {envelope.cont…How to Sync Two Directories in Python (rsync-like)
Mirror a source directory into a destination by copying new or changed files and deleting extras, similar to rsync.
import os
import shutil
import sys
from pathlib import Path
def sync_dirs(src: Path, dst: Path):
"""Mirror src into dst: copy new files, overwrite changed, delete extras."""
dst.mkdir(parents=True, exist_ok=True)
for dst_entry in dst.rglob('*'):
rel = dst_entry.relative_to(dst)
src_entry =…How to Track GitHub Stars, Forks, and Watchers in Python
Automatically fetch and track stars, forks, and watchers for multiple GitHub repositories, saving snapshots locally as JSON files for historical analysis.
import os
import time
import json
import requests
from pathlib import Path
from datetime import datetime
REPOS = [
"psf/requests",
"python/cpython",
"pallets/flask",
]
DATA_DIR = Path("github_metrics")
def fetch_repo_stats(repo):
url = f"https://api.github.com/repos/{repo}"
resp = requests.get(ur…How to Validate SSL Certificates for Multiple Domains in Python
A Python utility that checks SSL certificate expiry dates for a list of domains using the standard library ssl and socket modules.
import ssl
import socket
from datetime import datetime
def check_ssl_certificate(hostname: str, port: int = 443) -> dict:
"""Validate SSL certificate for a given hostname."""
context = ssl.create_default_context()
with socket.create_connection((hostname, port), timeout=5) as sock:
with context.wra…How to apply Kubernetes YAML files from a folder in Python
Uses the Kubernetes Python client to apply all YAML manifests in a directory, with sorted processing and per-file error handling.
import os
import yaml
from kubernetes import client, config
from kubernetes.utils import create_from_yaml
def apply_yaml_folder(folder_path):
"""Apply all YAML files in a folder using the Kubernetes mock client."""
# Load mock configuration
config.load_kube_config()
k8s_client = client.ApiClient()
…How to check Python files for common coding mistakes
Walks a directory tree parsing each .py file with ast, reporting empty functions, bare try blocks, too many parameters, and empty classes.
import ast
import os
import sys
def check_file(filepath):
try:
with open(filepath) as f:
code = f.read()
tree = ast.parse(code, filename=filepath)
except SyntaxError as e:
print(f"{filepath}: SyntaxError: {e.msg}")
return
issues = []
for node in ast.wal…Mount ISO Loop Device Mock Script in Python
Simulate ISO mounting with a loop device using a mock class — useful for testing scripts that depend on mount/unmount without actual system privileges.
import os
import tempfile
from dataclasses import dataclass
from pathlib import Path
@dataclass
class LoopDevice:
path: str
iso_path: str
mounted: bool = False
def mount(self, mount_point: str):
if self.mounted:
raise RuntimeError(f"Loop device {self.path} already mounted")
…Python: Archive Old Logs by Compressing Gzip by Age
A Python script that finds .log files older than a specified age and compresses them into .gz archives while removing the originals.
import gzip
import os
import shutil
from pathlib import Path
def archive_logs(log_dir: str, max_age_days: int) -> list[str]:
"""Compress log files older than max_age_days into .gz archives.
Returns a list of compressed file paths.
"""
cutoff = time.time() - max_age_days * 86400
compressed = …Scrape HTML Tables in Python with html.parser
Extract data from HTML tables using Python's built-in html.parser module, without third-party dependencies, by overriding callback methods to track table, row, and cell states.
import html.parser
from urllib.request import urlopen
class TableParser(html.parser.HTMLParser):
def __init__(self):
super().__init__()
self.in_table = False
self.in_row = False
self.in_cell = False
self.current_cell = []
self.rows = []
self.row = []
d…Track File Changes with Version History in Python
A Python utility that monitors a file for changes, creating versioned backups with SHA-256 hashing to detect modifications and store a local JSON history.
import hashlib, json, os, shutil, time
from pathlib import Path
class FileTracker:
def __init__(self, history_file="file_history.json"):
self.history_file = Path(history_file)
self.history = self._load_history()
def _load_history(self):
if self.history_file.exists():
retur…Track Internet Connectivity and Downtime Automatically in Python
Monitors internet connectivity by pinging a remote host and logs any downtime events with timestamps and duration.
import time
import subprocess
from datetime import datetime
def check_internet(host="8.8.8.8", timeout=3):
"""Returns True if internet is reachable via ping."""
try:
subprocess.run(
["ping", "-c", "1", "-W", str(timeout), host],
capture_output=True,
timeout=timeout …Build a Python Utility That Detects Duplicate Records Across Multiple Excel Sheets
A Python utility that uses pandas to find overlapping records across different Excel sheets based on specified key columns.
import pandas as pd
from pathlib import Path
def find_duplicate_records_across_sheets(file_path: str, key_columns: list, sheet_names: list) -> dict:
"""
Detect duplicate records across multiple Excel sheets based on specified key columns.
Args:
file_path: Path to the Excel file
key_co…Deduplicate events by ID within a window in Python
Deduplicate event streams by ID within sliding time windows, keeping the newest occurrence per window using heaps and sets.
import heapq
from collections import defaultdict
def deduplicate_events(events, window_size):
"""Return events deduplicated by id, keeping newest within each sliding window."""
# Index events by (timestamp, id) for deterministic ordering
events_by_id = defaultdict(list)
for ts, eid, *payload in events…Enrich a stream with reference data by key lookup in Python
Uses streamz to join each incoming record to a reference dictionary by name, adding department and level fields or defaults.
from streamz import Stream
reference = {"alice": {"dept": "eng", "level": 3}, "bob": {"dept": "sales", "level": 5}}
def enrich(record):
name = record.get("name")
ref = reference.get(name)
joined = dict(record)
if ref:
joined.update(ref)
else:
joined["dept"] = "unknown"
joi…Extract Schema.org Structured Data from Any Website in Python
A Python tool that fetches a webpage and extracts all JSON-LD structured data (Schema.org) embedded in <script> tags with type="application/ld+json".
import requests
from bs4 import BeautifulSoup
import json
def extract_schema_org(url):
"""Extract structured data (Schema.org) from a website."""
try:
response = requests.get(url, timeout=10)
response.raise_for_status()
except requests.exceptions.RequestException as e:
return {"err…How to Count Events by Minute with a Tumbling Window in Python
Group timestamps into fixed 60-second tumbling windows and count events per bucket using a dict.
from collections import defaultdict
from datetime import datetime, timedelta
def tumbling_window_count(events, window_seconds=60):
buckets = defaultdict(int)
for event in events:
ts = datetime.fromisoformat(event["timestamp"])
bucket_start = ts - timedelta(seconds=ts.second % window_seconds,
…How to Find Missing Values in Large Datasets in Python
Analyze missing values across multiple large pandas DataFrames with counts and percentages.
import pandas as pd
import numpy as np
def find_missing_values_summary(datasets):
"""Analyze missing values across multiple datasets (dict of name: DataFrame)."""
summary = {}
for name, df in datasets.items():
missing_count = df.isnull().sum()
total_rows = len(df)
missing_pct = (mi…How to Implement SCD Type 1 Overwrite in Python with SQLite
Implement SCD Type 1 dimension updates in Python using SQLite — overwrite existing rows with new data while preserving keys.
import sqlite3
# Simulate a dimension table with SCD Type 1 (overwrite)
conn = sqlite3.connect(":memory:")
cursor = conn.cursor()
# Create dimension table
cursor.execute("""
CREATE TABLE customer_dim (
customer_id INTEGER PRIMARY KEY,
customer_name TEXT,
city TEXT,
updated_at TEXT…How to Implement Slowly Changing Dimension Type 2 History in Python
Build a type-2 slowly changing dimension pipeline that closes old records and opens new ones when customer data changes.
from datetime import datetime, timedelta
def apply_scd_type2(records, current_date):
"""Returns active records after inserting new records with type-2 history."""
history = []
active = {}
for record in records:
key = record["customer_id"]
if key in active:
active[key]["end…Browse by section
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