app.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Copyright (c) 2020 Peter Siebler
#
# All rights reserved. This program and the accompanying materials
# are made available under the terms of the Distribution License
# which accompanies this distribution.
#
# Contributors:
#    Peter Siebler - initial implementation
#
# Copyright (c) 2020 Peter Siebler
# All rights reserved.

import sys

# simple check if python 3 is used
if not (sys.version_info.major == 3 and sys.version_info.minor >= 5):
    print("This script requires Python 3.5 or higher!")
    print("You are using Python {}.{}.".format(sys.version_info.major, sys.version_info.minor))
    sys.exit(1)

## all requirements
try:
    import os.path
    import paho.mqtt.client as mqtt
    import json
    import threading
    import time
    from time import sleep
    from uptime import uptime
    from lib import logger, calc
except Exception as e:
    print('Import error {}, check requirements.txt'.format(e))
    sys.exit(1)

try:
  from config import *
except Exception as e:
    print('Configuration error {}, check config.py'.format(e))
    sys.exit(1)


# register the application logger
appLogger = logger.Log(__name__, LOG_LEVEL, LOG_DIR)


def up_time():

    total_seconds = uptime()

    # Helper vars:
    MINUTE = 60
    HOUR = MINUTE * 60
    DAY = HOUR * 24

    # Get the days, hours, etc:
    days = int(total_seconds / DAY)
    hours = int((total_seconds % DAY) / HOUR)
    minutes = int((total_seconds % HOUR) / MINUTE)
    seconds = int(total_seconds % MINUTE)

    # Build up the pretty string (like this: "N days, N hours, N minutes, N seconds")
    string = ""
    if days > 0:
        string += str(days) + " " + (days == 1 and "day" or "days") + ", "
    if len(string) > 0 or hours > 0:
        string += str(hours) + " " + (hours == 1 and "hour" or "hours") + ", "
    if len(string) > 0 or minutes > 0:
        string += str(minutes) + " " + (minutes == 1 and "minute" or "minutes") + ", "
    string += str(seconds) + " " + (seconds == 1 and "second" or "seconds")

    return string


def WatermeterData():
    """Main Application
    """

    def on_connect(client, userdata, flags, rc):
        # The callback for when the client receives a CONNACK response from the server.
        if rc == mqtt.CONNACK_ACCEPTED:
            appLogger.logger.debug(f"❖ {MQTT_HOST} connected OK, subscribe to topic {MQTT_TOPIC}")
            # Subscribing in on_connect() means that if we lose the connection and
            # reconnect then subscriptions will be renewed.
            client.subscribe(MQTT_TOPIC)
        else:
            appLogger.logger.error(f"😡 {MQTT_HOST} Bad connection, returned code= {rc}")

    def on_publish(client, userdata, mid):
        appLogger.logger.debug(f"❖ Message Id {str(mid)} published.")

    def on_message(client, userdata, msg):
        # The on_message callback is called for each message received ...
        appLogger.logger.info(f" ❖ MQTT Message received topic {msg.topic}")
        # application state
        if(APP_STATEINFO):
            APP_STATEINFO["timestamp"] = now.strftime(DATEFORMAT_CURRENT)
            APP_STATEINFO["time"] = time.ctime()
            APP_STATEINFO["uptime"] = up_time()
            # publish state
            appLogger.logger.info(f" ❖ MQTT Publish state topic {MQTT_STATE_TOPIC}")
            client.publish(MQTT_STATE_TOPIC, json.dumps(APP_STATEINFO))
            # reset state
            APP_STATEINFO["state"] = 'waiting'
            APP_STATEINFO["synctime"] = -1
        # make all calculations
        if(msg.topic == MQTT_TOPIC):
            # make the calculations
            calcModul = calc.Calculator(client)
            lastData = calcModul.getResult(msg.payload)
            # reset state
            APP_STATEINFO["lastdata"] = now.strftime(DATEFORMAT_CURRENT)
            APP_STATEINFO["synctime"] = str(calcModul.elapsed_time)
            APP_STATEINFO["state"] = calcModul.state

    def on_disconnect(client, userdata, rc):
        # he on_disconnect() callback is called when the client disconnects from the broker.
        if rc != 1:
            appLogger.logger.info(f" ❖ Watermeter MQTT Client {MQTT_HOST} {MQTT_AVAILABILITY_TOPIC} got disconnected (code: {rc}")

    def on_log(client, userdata, level, buf):
        appLogger.logger.debug(f"❖ Mqtt Logmessage {level}:  {buf}")

    appLogger.logger.debug(f"❖ Watermeter MQTT Client {MQTT_HOST}")
    mqttclient = mqtt.Client()

    # Assign event callbacks
    mqttclient.on_connect = on_connect
    mqttclient.on_publish = on_publish
    mqttclient.on_message = on_message
    mqttclient.on_disconnect = on_disconnect

    # enable /disable logging
    if MQTT_ENABLE_LOGGING:
        appLogger.logger.info(f" ❖ Enable Logging for {MQTT_HOST}")
        mqttclient.on_log = on_log
        # mqttclient.enable_logger(appLogger.logger.logger)

    # Connect to mqtt brocker
    appLogger.logger.info(f" ❖ Watermeter connect to MQTT Client {MQTT_HOST}, {MQTT_AVAILABILITY_TOPIC}")
    try:
        # To connect with a username and password, call username_pw_set() before connecting:
        mqttclient.username_pw_set(MQTT_APPID, MQTT_PASSWORD)
        # Set a Will to be sent by the broker in case the client disconnects unexpectedly.
        mqttclient.will_set(MQTT_AVAILABILITY_TOPIC, 'Offline', 2, True)
        # conect to the MQTT Broker
        mqttclient.connect(MQTT_HOST, MQTT_PORT, keepalive=MQTT_KEEPALIVE)
    except:
        appLogger.logger.error()(f"😡 Error Connection for {MQTT_HOST}, check your settings or mqtt installation !")
        sys.exit(-1)

    # Wait until we've connected
    while not not mqttclient.is_connected():  # wait in loop
        appLogger.logger.debug(f"❖ Waiting for connection {MQTT_HOST}")
        time.sleep(1)

    # publish online state
    mqttclient.publish(MQTT_AVAILABILITY_TOPIC, 'Online', 2, True)

    # The loop_forever call blocks the main thread and so it will never terminate.
    # Press crtl+c to exit
    mqttclient.loop_forever()


# Start main application
appLogger.logger.info(" ❖ Watermeter data application start  --------------------")
WatermeterData()