aiooui

Source Code: https://github.com/bluetooth-devices/aiooui

Async OUI lookups

Installation

Install this via pip (or your favourite package manager):

pip install aiooui

Usage

Start by importing it:

import aiooui

await aiooui.async_load()
aiooui.get_vendor("00:00:00:11:22:33")  # "XEROX CORPORATION"

How lookups work

The OUI table (src/aiooui/oui.data, ~40k entries, ~770 KB) is not loaded into a dict. async_load() memory-maps the file read-only in an executor, and get_vendor() binary-searches the key array in place with bisect, so the search itself runs in C. The process keeps almost no private memory for the table (against ~5.6 MB for a dict). async_load() touches every page once, in the executor, so lookups on the event loop never wait on disk. Those pages are clean, shared page cache that the kernel can reclaim under memory pressure. If mmap is unavailable, the file is read into bytes and searched the same way.

Data file format

oui.data is a small binary table, all integers little-endian uint32:

Regenerate it only with python build_oui.py, which downloads the IEEE list, then validates, sorts and packs the entries. The release build runs it before packaging, so every release ships fresh data. tests/test_init.py::test_data_file_is_valid fails if the file is out of order or malformed. An unsorted key array would make lookups silently return None.

Contributors ✨

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!

Credits

This package was created with Copier and the browniebroke/pypackage-template project template.