Problem importing python output with command_line

Configuration
1

Im trying to import distance from a hc-sr04 (ultrasonic sensor) with a python script by using command_line platform but i only get “Command failed: python3 /home/pi/rpi-examples/HC-SR04/python/distance.py” in my logs… the script works if i run it in the terminal.

this is from my config file.

  • platform: command_line
    name: pellets
    scan_interval: 5
    command: “python3 /home/pi/rpi-examples/HC- SR04/python/distance.py”
    unit_of_measurement: “C”

and this is from my python script
import RPi.GPIO as GPIO
import time
import signal
import sys

# use Raspberry Pi board pin numbers
GPIO.setmode(GPIO.BCM)

# set GPIO Pins
pinTrigger = 18
pinEcho = 24

def close(signal, frame):
    print("\nTurning off ultrasonic distance detection...\n")
    GPIO.cleanup() 
    sys.exit(0)

signal.signal(signal.SIGINT, close)

# set GPIO input and output channels
GPIO.setup(pinTrigger, GPIO.OUT)
GPIO.setup(pinEcho, GPIO.IN)

while True:
    # set Trigger to HIGH
    GPIO.output(pinTrigger, True)
    # set Trigger after 0.01ms to LOW
    time.sleep(0.00001)
    GPIO.output(pinTrigger, False)

    startTime = time.time()
    stopTime = time.time()

    # save start time
    while 0 == GPIO.input(pinEcho):
        startTime = time.time()

    # save time of arrival
    while 1 == GPIO.input(pinEcho):
        stopTime = time.time()

    # time difference between start and arrival
    TimeElapsed = stopTime - startTime
    # multiply with the sonic speed (34300 cm/s)
    # and divide by 2, because there and back
    distance = (TimeElapsed * 34300) / 2

    print ("%.1f " % distance)
    time.sleep(1)
    GPIO.cleanup() 
    quit()

maby im thinking this all wrong? shouldnt ha be able to extract the printed value? im noob at both ha and python :stuck_out_tongue:

if i do this it works like a charm

print(“35”)

2

You need to check it works when using the same user as HA. So for hassbian, make sure the script runs as expected as homeassistant user.

3

Thanks gpbenton!
the script didnt run as expected.

i logged in as homeassistant venv user and noticed that the rpi.gpio wasnt installed in the venv, i installed it and now it works :slight_smile:

so i did:

$ sudo -u homeassistant -H -s
$ source /srv/homeassistant/bin/activate

ran:

python3 /home/pi/rpi-examples/HC-SR04/python/distance1.py

got:

Traceback (most recent call last):
File “/home/pi/rpi-examples/HC-SR04/python/distance1.py”, line 2, in module import RPi.GPIO as GPIO

ran:

pip3 install RPi.GPIO

and it works :slight_smile:

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