HomeServerIOExt/ioext/ioext.py

#!/usr/bin/python3 -u
#
import serial
from time import sleep
import os
import sys
import paho.mqtt.client as mqtt
import json
from datetime import datetime

# --- CONFIGURATION ---
import config
# --- END CONFIGURATION ---



# --- GLOBAL VARS ---
noReceiveCount = 0  # increase everytime the serial readline times out (1s timeout)
#getStatusCount = 0  # used as heartbeat, get status every 30s
verbose = False
debug = False
quiet = True

lastState_P2 = None
lastState_P3 = None
lastState_P4 = None
# --- END GLOBAL VARS ---


if len(sys.argv) >= 2:
    if sys.argv[1] == "-q":
        verbose = False
        debug = False
        quiet = True
        #print("VERBOSE=ON")
    elif sys.argv[1] == "-v":
        verbose = True
        debug = False
        quiet = False
        #print("VERBOSE=ON")
    elif sys.argv[1] == "-d":
        verbose = True
        quiet = False
        debug = True
        #print("DEBUG=ON")


def on_connect(client, userdata, flags, rc):
    if not quiet:
        print("MQTT connected with result code " + str(rc))
    #client.subscribe(mqtt_topic_cmd)
    
#def on_message(client, userdata, msg):    
#    if msg.topic == mqtt_topic_cmd:
#        payload = msg.payload.decode('ascii')
#        if payload == "status" or payload == "get conf" or payload == "clear" or payload == "open door" or payload.startswith("set prof ") or payload.startswith("set conf "):
#            if verbose:
#                print("serCmd: " + payload)
#            serCmd = payload + '\n'
#            ser.write(serCmd.encode('ascii'))
#        elif verbose:
#            print("unknown command:", payload)

def touch(fname, times=None):
    with open(fname, 'a'):
        os.utime(fname, times)

mqttc = mqtt.Client()
mqttc.on_connect = on_connect
#mqttc.on_disconnect = on_disconnect
#mqttc.on_message = on_message

mqttc.username_pw_set(config.mqtt_user, config.mqtt_password)
mqttc.connect(config.mqtt_server, config.mqtt_port, 60)

mqttc.loop_start()

ser = serial.Serial(port=config.serialPort,
    baudrate = config.serialBaud,
    parity=serial.PARITY_NONE,
    stopbits=serial.STOPBITS_ONE,
    bytesize=serial.EIGHTBITS,
    timeout=config.serialTimeout)
    


try:
    while True:
        ##ser.flushInput()        ## attention truncates incoming strings if there is little time between them 
        
        #read buffer until cr/lf
        serLine = ser.readline().strip()
        
        # catch exception on invalid char coming in: UnicodeDecodeError: 'ascii' codec can't decode byte 0xf4 in position 6: ordinal not in range(128)
        try: 
            serLine = serLine.decode('ascii')
        except:
            serLine = ""
        
        # if there came something in...
        if(serLine):
            noReceiveCount = 0
            
            # touch status file if configured
            try:
                config.statusFile
            except:
                if debug:
                    print("statusFile not defined")
            else:
                if config.statusFile is not None and config.statusFile != "":
                    try:
                        touch(config.statusFile)
                    except:
                        if debug:
                            print("ERROR - could not touch statusFile '" + str(config.statusFile) + "'")
                else:
                    if debug:
                        print("statusFile not configured")                        
            
            if verbose:
                print ('RX: ' + repr(serLine))    #Echo the serial buffer bytes up to the CRLF back to screen
            mqttc.publish(config.mqtt_base_topic + "/RX", str(serLine), qos=0, retain=False)
            
            # digital input P2
            if serLine.startswith('P2='):
                newState = None
                if serLine == "P2=L":
                    newState = "OFF"
                elif serLine == "P2=H":
                    newState = "ON"
                    
                if newState is not None and (lastState_P2 != newState or not config.P2_MQTT_SendOnlyIfValueChanged):
                    lastState_P2 = newState
                    mqttc.publish(config.P2_MQTT_Topic, newState, qos=0, retain=config.P2_MQTT_SendRetained)
                    if config.P2_MQTT_SendLastUpdate:
                        mqttc.publish(config.P2_MQTT_Topic + "_lastUpdate", datetime.now().isoformat(), qos=0, retain=config.P2_MQTT_SendRetained)
                    
            # digital input P3
            if serLine.startswith('P3='):
                newState = None
                if serLine == "P3=L":
                    newState = "OFF"
                elif serLine == "P3=H":
                    newState = "ON"
                    
                if newState is not None and (lastState_P3 != newState or not config.P3_MQTT_SendOnlyIfValueChanged):
                    lastState_P3 = newState
                    mqttc.publish(config.P3_MQTT_Topic, newState, qos=0, retain=config.P3_MQTT_SendRetained)
                    if config.P3_MQTT_SendLastUpdate:
                        mqttc.publish(config.P3_MQTT_Topic + "_lastUpdate", datetime.now().isoformat(), qos=0, retain=config.P3_MQTT_SendRetained)
            
            # digital input P4
            if serLine.startswith('P4='):
                newState = None
                if serLine == "P4=L":
                    newState = "OFF"
                elif serLine == "P4=H":
                    newState = "ON"
                
                if newState is not None and (lastState_P4 != newState or not config.P4_MQTT_SendOnlyIfValueChanged):
                    lastState_P4 = newState
                    mqttc.publish(config.P4_MQTT_Topic, newState, qos=0, retain=config.P4_MQTT_SendRetained)
                    if config.P4_MQTT_SendLastUpdate:
                        mqttc.publish(config.P4_MQTT_Topic + "_lastUpdate", datetime.now().isoformat(), qos=0, retain=config.P4_MQTT_SendRetained)
                   
            # DHT TH sensor
            # {"T":26.60,"H":36}
            if serLine.startswith('{"T":'):
                th = json.loads(serLine)
                t = round(float(th["T"]), 1)
                h = int(th["H"])
                if t >= -20 and t <= 50:
                    mqttc.publish(config.DHT22_MQTT_Topic_Temp, str(t), qos=0, retain=config.DHT22_MQTT_SendRetained)
                if h >= 0 and h <= 100:
                    mqttc.publish(config.DHT22_MQTT_Topic_Hum, str(h), qos=0, retain=config.DHT22_MQTT_SendRetained)
                if config.DHT22_MQTT_SendLastUpdate:
                        mqttc.publish(config.DHT22_MQTT_Topic_Temp + "_lastUpdate", datetime.now().isoformat(), qos=0, retain=config.DHT22_MQTT_SendRetained)
                
        # nothing came in this time...
        else:
            noReceiveCount += 1
            if debug:
                print("noReceiveCount=" + str(noReceiveCount))
            
            # quit script if nothing has been received for some time - will be restarted by systemd
            if noReceiveCount >= config.quitOnNoReceiveTimeout:
                quit()
            
except KeyboardInterrupt:
    print('\n')