iana-ports-query.py

# courtesy of chatgpt

import csv
from tabulate import tabulate
import re

# you need to download this file from the official iana website
CSV_FILE = "service-names-port-numbers.csv"
MAX_WIDTH = 80  # maximum width for displayed fields

def clean_text(text):
    """Replace newlines with '. ', collapse spaces, and truncate."""
    if text is None:
        return ""
    # Normalize whitespace and replace newlines
    text = re.sub(r'[\r\n]+', '. ', str(text))
    text = re.sub(r'\s+', ' ', text).strip()
    # Truncate if needed
    return text if len(text) <= MAX_WIDTH else text[:MAX_WIDTH - 3] + "..."

def load_ports(filename):
    ports = []
    with open(filename, newline='', encoding='utf-8') as f:
        reader = csv.DictReader(f)
        for row in reader:
            try:
                row['Port Number'] = int(row['Port Number'])
            except ValueError:
                continue
            ports.append(row)
    return ports

def query_ports(ports, query):
    query = query.strip()
    if '-' in query:
        try:
            start, end = map(int, query.split('-', 1))
        except ValueError:
            print("❌ Invalid range format. Use e.g. 20-25.")
            return []
        result = {}
        for p in ports:
            num = p['Port Number']
            if start <= num <= end and num not in result:
                result[num] = p
        return list(result.values())
    else:
        try:
            port = int(query)
        except ValueError:
            print("❌ Invalid port number.")
            return []
        return [p for p in ports if p['Port Number'] == port]

def display_results(results):
    if not results:
        print("No matches found.")
        return

    table = [
        [
            r['Port Number'],
            clean_text(r['Service Name']),
            clean_text(r['Description']),
            clean_text(r['Assignment Notes'])
        ]
        for r in results
    ]
    print(tabulate(
        table,
        headers=["Port", "Service Name", "Description", "Assignment Notes"],
        tablefmt="github"
    ))

def main():
    print("Loading port data...")
    ports = load_ports(CSV_FILE)
    print(f"Loaded {len(ports)} entries.")
    print("Enter a port number (e.g., 80) or range (e.g., 20-25). Type 'exit' to quit.")
    
    while True:
        query = input("Query> ").strip()
        if query.lower() in ('exit', 'quit'):
            break
        results = query_ports(ports, query)
        display_results(results)

if __name__ == "__main__":
    main()