uns-kit 0.0.28

Lightweight Python UNS MQTT client (pub/sub + infra topics)

uns-kit (Python)

Lightweight UNS MQTT client for Python. Provides:

• Topic builder compatible with UNS infra topics (uns-infra/<package>/<version>/<process>/).
• Async publish/subscribe via MQTT (using aiomqtt).
• Process + instance status topics (active/heap/uptime/alive + stats).
• Minimal UNS packet builder/parser (data/table) aligned with TS core.

Install (editable)

cd packages/uns-py
poetry install

CLI

After poetry install, an uns-kit-py command is available (renamed to avoid clashing with the Node CLI):

poetry run uns-kit-py publish --host localhost:1883 --topic raw/data/ --value 1
poetry run uns-kit-py subscribe --host localhost:1883 --topic 'uns-infra/#'

Quick start

import asyncio
from pathlib import Path
from uns_kit import UnsConfig, UnsPacket, UnsProxyProcess

async def main():
    config = UnsConfig.load(Path("config.json"))
    process = UnsProxyProcess(config.infra_host, config=config)
    await process.start()
    mqtt = await process.create_mqtt_proxy("py")

    # Subscribe
    async with mqtt.client.messages("uns-infra/#") as messages:
        await mqtt.publish_packet("raw/data/", UnsPacket.data(value=1, uom="count"))
        msg = await messages.__anext__()
        print(msg.topic, msg.payload.decode())

    await mqtt.close()
    await process.stop()

asyncio.run(main())

Resilient subscriber

async for msg in client.resilient_messages("uns-infra/#"):
    print(msg.topic, msg.payload.decode())

Examples

• examples/publish.py — publish 5 data packets.
• examples/subscribe.py — resilient subscription with auto-reconnect.
• examples/load_test.py — interactive publish burst.

Create a new project

uns-kit-py create my-uns-py-app
cd my-uns-py-app
poetry install
poetry run python src/main.py

Create a sandbox app in this repo

From the monorepo root:

pnpm run py:sandbox

This creates sandbox-app-py/ using the default Python template.

Notes

• Default QoS is 0.
• Instance status topics are published every 10 seconds; stats every 60 seconds.
• Packet shape mirrors the TypeScript core: {"version":"1.3.0","message":{"data":{...}},"sequenceId":0}.
• Windows: the library sets WindowsSelectorEventLoopPolicy() to avoid add_reader/add_writer NotImplementedError.

TODO (parity with TS core)

• Handover manager (cross-version active detection + handover_* messages).
• Publish throttling/queue.
• Status parity (publisher/subscriber active flags everywhere, richer metrics).
• API endpoints registry (to mirror @uns-kit/api produced endpoints).
• Optional: dictionary/measurement helpers + CLI wrapper.