systemd Service Notification

This is a Calian fork of Garrett's Asyncio version (https://github.com/seatsnob/sdnotify-asyncio) of the systemd sd_notify package written by bb4242 (Brett Bethke), available at https://github.com/bb4242/sdnotify

This is a pure Python implementation of the systemd sd_notify protocol. This protocol can be used to inform systemd about service start-up completion, watchdog events, and other service status changes. Thus, this package can be used to write system services in Python that play nicely with systemd. async-sdnotify is compatible with Python 3.

Normally the SystemdNotifier.notify method silently ignores exceptions (for example, if the systemd notification socket is not available) to allow applications to function on non-systemd based systems. However, setting debug=True will cause this method to raise any exceptions generated to the caller, to aid in debugging.

Installation

pip install async-sdnotify

Example Usage

This is an example of a simple Python service that informs systemd when its startup sequence is complete. It also sends periodic status updates to systemd, which can be viewed with systemctl status test.

test.py

import aiosdnotify
import asyncio

async def main():
    print("Test starting up...")
    # In a real service, this is where you'd do real startup tasks
    # like opening listening sockets, connecting to a database, etc...
    await asyncio.sleep(2)
    print("Test startup finished")
    
    # Inform systemd that we've finished our startup sequence...
    async with aiosdnotify.SystemdNotifier() as n:
        n.ready()
        
        count = 1
        while True:
            print("Running... {}".format(count))
            n.status("Count is {}".format(count))
            count += 1
            await asyncio.sleep(2)

test.service

[Unit]
Description=A test service written in Python

[Service]
# Note: setting PYTHONUNBUFFERED is necessary to see the output of this service in the journal
# See https://docs.python.org/2/using/cmdline.html#envvar-PYTHONUNBUFFERED
Environment=PYTHONUNBUFFERED=true

# Adjust this line to the correct path to test.py
ExecStart=/usr/bin/python /path/to/test.py

# Note that we use Type=notify here since test.py will send "READY=1"
# when it's finished starting up
Type=notify

[Install]
WantedBy=multi-user.target