plugin.py

# Basic Python Plugin Example
#
# Author: akamming 
#
"""
<plugin key="WMPS" name="WaterMeter NPN plugin" author="akamming" version="1.0.2" wikilink="https://www.domoticz.com/wiki/Plugins" externallink="https://www.google.com/">
    <description>
        <h2>Watermeter</h2><br/>
        Plugin version of the Watermeter python script using a NPN sensor<br/>
        <h3>Features</h3>
        <ul style="list-style-type:square">
            <li>Exports the pin (not necessary to do before starting domoticz)</li>
            <li>Is  run from within domoticz (no need for making sure a seperate python scripts keeps up and running on your pi)</li>
            <li>Creates the watermeterdevice (no need for giving special http commands to create the needed device) </li>
            <li>Allow for overriding the meter reading manually (change the meterstand.txt to the meterstand you need) </li>
        </ul>
        <h3>Devices</h3>
        <ul style="list-style-type:square">
            <li>WaterMeter - Counts the liters of water running through your watermeter</li>
        </ul>
        <h3>Configuration</h3>
        Configure correctly. The plugin works using the default settings, but your system might need different settings...
        <ul style="list-style-type:square">
            <li>GPIO Pin Number - The GPIO Pin (BCM!) to which your NPN sensor is connected. To avoid conflicts, make sure the GPIO pin is not managed/configured somewhere else on your system to prevent confllicts. You can still use the normal GPIO drivers in domoticz for other pins as long as you don't configure the same pins.</li>
            <li>Debounce Time - Configure the cooldown time after the interrupt to prevent interrupt flooding. A high number is recommended, but it should be less then the time it takes to have 1 liter going throught your watermeter, to prevent lost measurements.</li> 
            <li>Meter Reading File - The path of the file where you want the actual meter reading to be stored. If you do not specifiy a path, the homefolder of this plugin will be used</li>
            <li>Increment - The amount your domoticz counter must be incremented when a pulse of the watermeter is detected. In NL this is normally 1 liter. In belgium apparently this is 2 ticks per liter (value should then be 0.5).</li>

            <br/>
            Last but not least: A normal (Dutch) watermeter measures 1 liter every pulse on the GPIO pin. The meter in domoticz is of the type M3. So in order to have this meter to show the correct amount, you have to change the RFX Meter/Counter Setup in domoticz. If this is not set correctly: <br />
            - Go to domoticz web interface<br/>
            - Click on Setup<br/>
            - Click on Settings<br/>
            - Click on Meters/Counters<br/>
            - Set the value of the water divider to 1000  (1 M3 = 1000 L ;-))<br/>
            - Click on Apply Settings  <br/><br/>
        </ul>
    </description>
    <params>
         <param field="Mode1" label="GPIO Pin Number" width="150px">
         <options>
            <option label="GPIO2" value="2" />
            <option label="GPIO3" value="3"/>
            <option label="GPIO4" value="4"/>
            <option label="GPIO5" value="5"/>
            <option label="GPIO6" value="6"/>
            <option label="GPIO7" value="7"/>
            <option label="GPIO8" value="8"/>
            <option label="GPIO9" value="9"/>
            <option label="GPIO12" value="12"/>
            <option label="GPIO13" value="13"/>
            <option label="GPIO14" value="14"/>
            <option label="GPIO15" value="15"/>
            <option label="GPIO16" value="16"/>
            <option label="GPIO17" value="17"/>
            <option label="GPIO18" value="18"/>
            <option label="GPIO19" value="19"/>
            <option label="GPIO20" value="20"/>
            <option label="GPIO21" value="21" default="true"/>
            <option label="GPIO22" value="22"/>
            <option label="GPIO23" value="23"/>
            <option label="GPIO24" value="24"/>
            <option label="GPIO25" value="25"/>
            <option label="GPIO26" value="26"/>
         </options>
         </param> 
         <param field="Mode4" label="Debounce time (ms)" width="150px" required="true">
         <options>
            <option label="0" value="0" />
            <option label="50" value="50" />
            <option label="100" value="100" />
            <option label="150" value="150" />
            <option label="200" value="200" />
            <option label="250" value="250" />
            <option label="300" value="300" />
            <option label="350" value="350" default="true"/>
            <option label="400" value="400" />
            <option label="450" value="450" />
            <option label="500" value="500" />
			<option label="750" value="500" />
            <option label="1000" value="1000" />
			<option label="1250" value="1250" />
            <option label="1500" value="1500" />
			<option label="1750" value="1750" />
            <option label="2000" value="2000" />
         </options>
         </param>
         <param field="Mode5" label="Meter Reading File" width="150px" required="true" default="meterstand_water.txt" />
         <param field="Mode6" label="Increment" width="70px" default="1"/> 
     </params>
</plugin>
"""
import Domoticz
from gpiozero import Button
import os
import time

#setup global vars
#global debug
#global fakereading

fakereading=False        # for testing purposes. Will generate a "tick" every 10 seconds

#Check if we have to go in debug mode
debug=False #True/False             # set to true to enable debug logging
#if os.path.exists(str(Parameters["HomeFolder"])+"DEBUG"): 

last_watermeter_value = 0

class BasePlugin:

    enabled = False
    def __init__(self):
        return

    def onStart(self):
        global debug
        global fakereading
        global gpio_pin
        global meter

        Domoticz.Log("Watermeter plugin started...")

        #Check if we have to switch on debug mode
        if os.path.exists(str(Parameters["HomeFolder"])+"DEBUG"): 
            debug=True
            Domoticz.Log("File "+str(Parameters["HomeFolder"])+"DEBUG"+" exists, switching on Debug mode")
        else:
            debug=False #True/False

        #Check if we have to switch on pulse for testin purposes
        if os.path.exists(str(Parameters["HomeFolder"])+"TESTPULSE"): 
            fakereading=True
            Domoticz.Log("Plugin is in testing mode, generates a tick every 10 seconds by itself!!, delete file "+str(Parameters["HomeFolder"])+"TESTPULSE to switch off")
        else:
            fakereading=False


        Debug("OnStart called")
		
        if debug==True:
            Debug("In Debug mode: Dumping config to log...") 
            DumpConfigToLog()

        #get pin config from settings
        gpio_pin=int(Parameters["Mode1"])

        Debug("Pin "+str(gpio_pin)+" was configured")

        # By default false positive checks are switched OFF
        check_last_value = False
        check_consistency = False

        fn=Parameters["Mode5"]
        increment=float(Parameters["Mode6"])
        Debug("Filename "+fn+" detected")
        Debug("increment "+str(increment)+" detected")


        # Setting up GPIO
        Debug("Setting up GPIO")
        meter=Button(gpio_pin)
        meter.when_pressed = Interrupt
        #meter.when_released= Interrupt

        #Create device if needed
        if (len(Devices) == 0):
            Debug("Creating watermeter device")
            Domoticz.Device(Name="Water Usage", Unit=1, Type=113, Subtype=0, Switchtype=2).Create()

        #Get current counter
        counter=GetMeterFile()
        InitialReading=0
        if counter==-1:
            Debug("No meter file, creating one with value  ("+str(InitialReading)+")")
            counter=InitialReading
            WriteMeterFile(counter)

        # Update Sensor with counter
        Devices[1].Update(nValue=int(counter), sValue=str(counter))


    def onStop(self):
        global meter

        Debug("onStop called")
        del meter

    def onConnect(self, Connection, Status, Description):
        Debug("onConnect called")

    def onMessage(self, Connection, Data):
        Debug("onMessage called")

    def onCommand(self, Unit, Command, Level, Hue):
        Debug("onCommand called for Unit " + str(Unit) + ": Parameter '" + str(Command) + "', Level: " + str(Level))

    def onNotification(self, Name, Subject, Text, Status, Priority, Sound, ImageFile):
        Debug("Notification: " + Name + "," + Subject + "," + Text + "," + Status + "," + str(Priority) + "," + Sound + "," + ImageFile)

    def onDisconnect(self, Connection):
        Debug("onDisconnect called")

    def onHeartbeat(self):
        global last_watermeter_value
        Debug("onHeartbeat called")
        if fakereading==True:
            Debug("FakeReading==True: Generating testpulse, not generated by watermeter itself!")
            Interrupt(1) #For testing purposes

        #Logging (Wordaround: domotic 2022.1 cause error in findmodule if log function is called during interrupt, so log in heartbeat if value has changed)
        counter=GetMeterFile()
        if last_watermeter_value!=counter:
            Domoticz.Log("RFXMeter/RFXMeter counter ("+Devices[1].Name+") - "+str(counter/1000)+" M3") 
            last_watermeter_value=counter


global _plugin
_plugin = BasePlugin()

def onStart():
    global _plugin
    _plugin.onStart()

def onStop():
    global _plugin
    _plugin.onStop()

def onConnect(Connection, Status, Description):
    global _plugin
    _plugin.onConnect(Connection, Status, Description)

def onMessage(Connection, Data):
    global _plugin
    _plugin.onMessage(Connection, Data)

def onCommand(Unit, Command, Level, Hue):
    global _plugin
    _plugin.onCommand(Unit, Command, Level, Hue)

def onNotification(Name, Subject, Text, Status, Priority, Sound, ImageFile):
    global _plugin
    _plugin.onNotification(Name, Subject, Text, Status, Priority, Sound, ImageFile)

def onDisconnect(Connection):
    global _plugin
    _plugin.onDisconnect(Connection)

def onHeartbeat():
    global _plugin
    _plugin.onHeartbeat()

    # Generic helper functions
def DumpConfigToLog():
    for x in Parameters:
        if Parameters[x] != "":
            Domoticz.Log( "'" + x + "':'" + str(Parameters[x]) + "'")
    Domoticz.Debug("Device count: " + str(len(Devices)))
    for x in Devices:
        Domoticz.Log("Device:           " + str(x) + " - " + str(Devices[x]))
        Domoticz.Log("Device ID:       '" + str(Devices[x].ID) + "'")
        Domoticz.Log("Device Name:     '" + Devices[x].Name + "'")
        Domoticz.Log("Device nValue:    " + str(Devices[x].nValue))
        Domoticz.Log("Device sValue:   '" + Devices[x].sValue + "'")
        Domoticz.Log("Device LastLevel: " + str(Devices[x].LastLevel))
    return

def GetMeterFile():
    fn=Parameters["Mode5"] # Get filename
    Debug("GetMeterFile() called")
    if os.path.exists(fn):
        f = open(fn, "r+")
        line = f.readline()
        a,b,c = line.split()
        Counter = float(c)
        Debug("Meter file exists, current counter is "+str(Counter))
        return Counter
    else:
        Debug("No Meter File found")
        return -1

def WriteMeterFile(counter):
    fn=Parameters["Mode5"] # get Filename
    Debug("WriteMeterFile("+str(counter)+") called")
    f = open( fn, 'w')
    f.write( 'meterstand = ' + repr(counter))
    f.close()

def Interrupt(channel):

    global interrupt
    global gpio_pin

    Debug("Processing Meter Pulse (1 liter water)")

    counter=GetMeterFile()
    if counter==-1:
        # counter=int(Parameters["Mode6"]) # Get initial value from settings
        counter=0 # Configured above in the script
        Debug("No meter file, creating a new one")
    else:
        increment=float(Parameters["Mode6"])
        counter+=increment 
        Debug("incremented counter to "+str(counter))

    WriteMeterFile(counter)

    #Create device if it is no longer there 
    if (len(Devices) == 0): 
        Debug("Watermeter device gone...Creating watermeter device")
        Domoticz.Device(Name="Water Usage", Unit=1, Type=113, Subtype=0, Switchtype=2).Create()
    
    #update the device with the found counter
    Devices[1].Update(nValue=int(counter), sValue=str(counter))
    #Domoticz.Log("RFXMeter/RFXMeter counter ("+Devices[1].Name+") - "+str(counter/1000)+" M3") ## temporarily disabled due to FindModule bug

def Debug(text):
    if (debug):
        Domoticz.Log(text)