sysinfo.py

# sudo nano /etc/init.d/pifacecadsysinfo # correct SYSINFO_FILE path
# sudo update-rc.d pifacecadsysinfo defaults

#!/usr/bin/env python3
import sys
import subprocess
from time import sleep
import pifacecad


UPDATE_INTERVAL = 60 * 5  # 5 mins
GET_IP_CMD = "hostname --all-ip-addresses"
GET_TEMP_CMD = "/opt/vc/bin/vcgencmd measure_temp"
TOTAL_MEM_CMD = "free | grep 'Mem' | awk '{print $2}'"
USED_MEM_CMD = "free | grep 'Mem' | awk '{print $3}'"

temperature_symbol = pifacecad.LCDBitmap(
    [0x4, 0x4, 0x4, 0x4, 0xe, 0xe, 0xe, 0x0])
memory_symbol = pifacecad.LCDBitmap(
    [0xe, 0x1f, 0xe, 0x1f, 0xe, 0x1f, 0xe, 0x0])
temp_symbol_index, memory_symbol_index = 0, 1


def run_cmd(cmd):
    return subprocess.check_output(cmd, shell=True).decode('utf-8')


def get_my_ip():
    return run_cmd(GET_IP_CMD)[:-1]


def get_my_temp():
    return run_cmd(GET_TEMP_CMD)[5:9]


def get_my_free_mem():
    total_mem = float(run_cmd(TOTAL_MEM_CMD))
    used_mem = float(run_cmd(USED_MEM_CMD))
    mem_perc = used_mem / total_mem
    return "{:.1%}".format(mem_perc)


def wait_for_ip():
    ip = ""
    while len(ip) <= 0:
        sleep(1)
        ip = get_my_ip()


def show_sysinfo():
    while True:
        cad.lcd.clear()
        cad.lcd.write("{}\n".format(get_my_ip()))

        cad.lcd.write_custom_bitmap(temp_symbol_index)
        cad.lcd.write(":{}C ".format(get_my_temp()))

        cad.lcd.write_custom_bitmap(memory_symbol_index)
        cad.lcd.write(":{}".format(get_my_free_mem()))
        sleep(UPDATE_INTERVAL)


if __name__ == "__main__":
    cad = pifacecad.PiFaceCAD()
    cad.lcd.blink_off()
    cad.lcd.cursor_off()

    if "clear" in sys.argv:
        cad.lcd.clear()
        cad.lcd.display_off()
        cad.lcd.backlight_off()
    else:
        cad.lcd.store_custom_bitmap(temp_symbol_index, temperature_symbol)
        cad.lcd.store_custom_bitmap(memory_symbol_index, memory_symbol)
        cad.lcd.backlight_on()
        cad.lcd.write("Waiting for IP..")
        wait_for_ip()
        show_sysinfo()