fronius-connector.py

#!/usr/bin/env python

"""Fetches some data from the fronius json api
and publishes the result to mqtt.
Read only."""

import paho.mqtt.client as paho  # pip install paho-mqtt
import requests
import time
import logging
import sys
from config import *


FREQUENCY = 3


def fronius_data():

    values = {}

    try:
        url = "http://{}/solar_api/v1/GetPowerFlowRealtimeData.fcgi".format(FRONIUS_HOST)  # noqa E501
        r = requests.get(url, timeout=FREQUENCY - 0.5)
        r.raise_for_status()
        powerflow_data = r.json()

        values['p_pv'] = powerflow_data['Body']['Data']['Site']['P_PV']
        values['p_grid'] = powerflow_data['Body']['Data']['Site']['P_Grid']
        values['p_akku'] = powerflow_data['Body']['Data']['Site']['P_Akku']
        values['p_load'] = -powerflow_data['Body']['Data']['Site']['P_Load']
        values['soc'] = powerflow_data['Body']['Data']['Inverters']['1'].get('SOC')
        values['battery_mode'] = powerflow_data['Body']['Data']['Inverters']['1'].get('Battery_Mode')
        values['e_day'] = powerflow_data['Body']['Data']['Inverters']['1']['E_Day'] / 1000

        # handling for null/None values
        for k, v in values.items():
            if v is None:
                values[k] = 0

    except requests.exceptions.Timeout:
        print("Timeout requesting {}".format(url))
    except requests.exceptions.RequestException as e:
        print("requests exception {}".format(e))

    return values


if __name__ == '__main__':
    logging.basicConfig(stream=sys.stderr, level=logging.INFO)
    logging.getLogger("urllib3").setLevel(logging.INFO)

    mqttc = paho.Client('fronius-connector', clean_session=True)
    # mqttc.enable_logger()
    mqttc.will_set("{}/connectorstatus".format(FRONIUS_MQTT_PREFIX), "Fronius Connector: LOST_CONNECTION", 0, retain=True)

    mqttc.connect(BROKER_HOST, BROKER_PORT, 60)
    logging.info("Connected to {}:{}".format(BROKER_HOST, BROKER_PORT))

    mqttc.publish("{}/connectorstatus".format(FRONIUS_MQTT_PREFIX), "Fronius Connector: ON-LINE", retain=True)

    mqttc.loop_start()
    while True:
        try:
            values = fronius_data()
            for k, v in values.items():
                (result, mid) = mqttc.publish("{}/{}".format(FRONIUS_MQTT_PREFIX, k), str(v), 0)
                logging.debug("Pubish Result: {} MID: {} for {}: {}".format(result, mid, k, v))  # noqa E501                

            time.sleep(FREQUENCY)
        except KeyboardInterrupt:
            break
        except Exception:
            raise

    mqttc.publish("{}/connectorstatus".format(FRONIUS_MQTT_PREFIX), "Fronius Connector: OFF-LINE", retain=True)

    mqttc.disconnect()
    mqttc.loop_stop()  # waits, until DISCONNECT message is sent out
    logging.info("Disconnected from to {}:{}".format(BROKER_HOST, BROKER_PORT))