update-oui-database

#!/usr/bin/env python3

import csv
import json
import os
import requests

DOWNLOAD_BUFFER_SIZE = 64 * 1024
DEFAULT_DB_NAME = "oui.json"

SOURCES = {
    "MA-S": "http://standards-oui.ieee.org/oui36/oui36.csv",
    "MA-M": "http://standards-oui.ieee.org/oui28/mam.csv",
    "MA-L": "http://standards-oui.ieee.org/oui/oui.csv",
}

# From https://stackoverflow.com/questions/16694907/download-large-file-in-python-with-requests
def download_db(url):
    local_filename = url.split('/')[-1]
    # NOTE the stream=True parameter below
    with requests.get(url, stream=True) as r:
        r.raise_for_status()
        with open(local_filename, 'wb') as f:
            for chunk in r.iter_content(chunk_size=DOWNLOAD_BUFFER_SIZE):
                # If you have chunk encoded response uncomment if
                # and set chunk_size parameter to None.
                #if chunk:
                f.write(chunk)
    return local_filename

def main():
    oui = []
    db_files = []
    for _, url in SOURCES.items():
        print(f"Downloading MAC database from {url}...")
        db_file = download_db(url)
        db_files.append(db_file)

    for db_file in db_files:
        print(f"Processsing MAC database {db_file}... ", end='')
        rows = 0
        with open(db_file, "r", newline="") as db:
            csv_file = csv.DictReader(db)
            for row in csv_file:
                oui.append({
                    "macPrefix": row["Assignment"].lower(),
                    "vendorName": row["Organization Name"]
                })
                rows += 1
        print(f"done ({rows} records).")

    output = DEFAULT_DB_NAME
    print(f"Writing new json database file ({output})... ", end='')
    with open(output, "w") as oui_file:
        json.dump(oui, oui_file)
    print(f"done ({len(oui)} records).")

    print("Deleting downloaded files...")
    for db_file in db_files:
        os.remove(db_file)

if __name__ == "__main__":
    main()