Reads statistics from readsb stats.json and forwards to homeassistant (HASS) via MQTT broker.

readsb-mqtt-stats-json.py

#! /usr/bin/python3

# Reads statistics from readsb stats.json and forwards to homeassistant (HASS)
# via MQTT broker.
#
# Dependencies:
#   pip3 install paho-mqtt
#   pip3 install watchdog

import sys
import signal
import json
import paho.mqtt.client as mqtt
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler

# MQTT broker configuration
MQTT_HOST = "localhost"
MQTT_USER = "user"
MQTT_PASSWORD = "pass"
MQTT_PORT = "1883"
MQTT_TOPIC_PREFIX = "homeassistant/sensor"
MQTT_CLIENT_ID = "feeder001"

statistics = [
    {"id": "messages", "name": "Messages", "unit": "Messages", "value": 0},
    {"id": "tracks_new", "name": "Tracking", "unit": "Aircraft", "value": 0},
    {"id": "tracks_single", "name": "Single", "unit": "Aircraft", "value": 0},
    {"id": "tracks_mlat", "name": "MLAT", "unit": "Aircraft", "value": 0},
    {"id": "tracks_position", "name": "Positions", "unit": "Aircraft", "value": 0},
    {"id": "max_dist_metric", "name": "Maximum Distance Metric", "unit": "km", "value": 0},
    {"id": "max_dist_imp", "name": "Maximum Distance Imperial", "unit": "nm", "value": 0},
    {"id": "local_strong", "name": "Strong Signals", "unit": "Messages", "value": 0},
    {"id": "local_signal", "name": "Signal", "unit": "dBFS", "value": 0},
    {"id": "local_noise", "name": "Noise", "unit": "dBFS", "value": 0},
    {"id": "local_peak", "name": "Peak", "unit": "dBFS", "value": 0},
    {"id": "temperatur", "name": "Temperature", "unit": "°C", "value": 0}
]

if __name__ == '__main__':
    def on_mqtt_message(mqttc, obj, msg):
        print(msg.topic + " " + str(msg.qos) + " " + str(msg.payload))

    def on_mqtt_disconnect(client, userdata, rc):
        if rc != 0:
            print("unexpected disconnection")
        global app_exit
        app_exit = True

    def on_mqtt_publish(client, userdata, mid):
        pass

    def signal_handler(signal, frame):
        global app_exit
        app_exit = True

    def update_from_stats(evt):
        global new_stats, last_timestamp, feeder_status
        if str(evt.dest_path).split("/").pop() == "stats.json":
            try:
                f = open(evt.dest_path, "rb")
                stats = json.load(f)
                f.close()
            except Exception as e:
                print("read json stats error: {}".format(e))
                return

            try:
                statistics[0]["value"] = int(stats["last1min"]["messages"])
                statistics[1]["value"] = int(stats["aircaft_with_pos"]) + int(stats["aircaft_without_pos"])
                statistics[2]["value"] = int(stats["last1min"]["tracks"]["single_message"])
                statistics[3]["value"] = int(stats["aircraft_count_by_type"]["mlat"])
                statistics[4]["value"] = int(stats["aircaft_with_pos"])
                statistics[5]["value"] = int(stats["last1min"]["max_distance"]) / 1000
                statistics[6]["value"] = int(stats["last1min"]["max_distance"]) * 0.0005399565
            except:
                statistics[0]["value"] = -1
                statistics[1]["value"] = -1
                statistics[2]["value"] = -1
                statistics[3]["value"] = -1
                statistics[4]["value"] = -1
                statistics[5]["value"] = -1
                statistics[6]["value"] = -1
            # Separate block, local only available when SDR connected, missing in --net-only
            try:
                statistics[7]["value"] = int(stats["last1min"]["local"]["strong_signals"])
                statistics[8]["value"] = int(stats["last1min"]["local"]["signal"])
                statistics[9]["value"] = int(stats["last1min"]["local"]["noise"])
                statistics[10]["value"] = int(stats["last1min"]["local"]["peak_signal"])
            except:
                statistics[7]["value"] = 0
                statistics[8]["value"] = 0
                statistics[9]["value"] = 0
                statistics[10]["value"] = 0

            if int(stats["now"]) - last_timestamp > 90:
                feeder_status = 0
            else:
                feeder_status = 1

            last_timestamp = int(stats.last_1min.stop)
            new_stats = True

        try:
            f = open("/sys/class/hwmon/hwmon0/temp1_input", "r")
            temp = int(f.readline())
            f.close()
            statistics[11]["value"] = temp / 1000
        except Exception as e:
            print("update error: {}".format(e))

    # Entry point
    app_exit = False
    new_stats = False
    feeder_status = 0
    last_timestamp = 0
    signal.signal(signal.SIGABRT, signal_handler)
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGINT, signal_handler)

    try:
        obs = Observer()
        evt = FileSystemEventHandler()
        obs.schedule(evt, "/run/readsb", recursive=False)
        evt.on_moved = update_from_stats
        obs.start()
    except Exception as e:
        print("observer error: {}".format(e))
        sys.exit(1)

    try:
        mqtt_client = mqtt.Client()
        mqtt_client.on_message = on_mqtt_message
        mqtt_client.on_disconnect = on_mqtt_disconnect
        mqtt_client.on_publish = on_mqtt_publish
        mqtt_client.username_pw_set(MQTT_USER, MQTT_PASSWORD)
        # Set last will: client not running
        topic = "{}/{}/properties".format(MQTT_TOPIC_PREFIX, MQTT_CLIENT_ID)
        payload = {"running": 0}
        mqtt_client.will_set(topic, json.dumps(payload), 1)
        mqtt_client.connect(MQTT_HOST, int(MQTT_PORT))
    except Exception as e:
        print("mqtt client error: {}".format(e))
        obs.stop()
        obs.join()
        sys.exit(1)

    mqtt_client.loop_start()

    while not app_exit:
        if new_stats:
            new_stats = False
            for entry in statistics:
                # Create topic configuration
                topic = "{}/{}/{}/config".format(MQTT_TOPIC_PREFIX, MQTT_CLIENT_ID, entry["id"])
                payload = {}
                payload["name"] = "{} {}".format(MQTT_CLIENT_ID, entry["name"])
                payload["unique_id"] = "{}.{}".format(MQTT_CLIENT_ID, entry["id"])
                payload["state_topic"] = "{}/{}/properties".format(MQTT_TOPIC_PREFIX, MQTT_CLIENT_ID)
                payload["val_tpl"] = "{{value_json.{}}}".format(entry["id"]),
                payload["icon"] = "mdi:airplane",
                payload["platform"] = "mqtt",
                payload["unit_of_measurement"] = entry["unit"]
                mqtt_client.publish(topic, json.dumps(payload), qos=1).wait_for_publish(1)
                print(topic)
                print(json.dumps(payload))

            # Create status configuration
            topic = "homeassistant/binary_sensor/{}/running/config".format(MQTT_CLIENT_ID)
            payload = {}
            payload["name"] = "{} Status".format(MQTT_CLIENT_ID)
            payload["unique_id"] = "{}.running".format(MQTT_CLIENT_ID)
            payload["device_class"] = "running"
            payload["state_topic"] = "{}/{}/properties".format(MQTT_TOPIC_PREFIX, MQTT_CLIENT_ID)
            payload["val_tpl"] = "{{value_json.running}}"
            payload["payload_on"] = "1"
            payload["payload_off"] = "0"
            payload["platform"] = "mqtt"
            mqtt_client.publish(topic, json.dumps(payload), qos=1).wait_for_publish(1)
            print(topic)
            print(json.dumps(payload))

            # Create properties
            topic = "{}/{}/properties".format(MQTT_TOPIC_PREFIX, MQTT_CLIENT_ID)
            payload = {}
            # for statistic entries
            for entry in statistics:
                payload[entry["id"]] = entry["value"]
            # and add feeder status
            payload["running"] = feeder_status
            mqtt_client.publish(topic, json.dumps(payload), qos=1).wait_for_publish(1)
            print(topic)
            print(json.dumps(payload))

    # Clean up and exit
    obs.stop()
    obs.join()
    mqtt_client.disconnect()
    mqtt_client.loop_stop()
    sys.exit(0)