Raspberry Pi Pico W の温度センサで取得したデータを Prometheus Pushgateway に Push する Micro Python コード

main.py

import gc
import machine
import network
import urequests
import utime

GATEWAY_HOST = "<Pushgateway host IP>"
GATEWAY_PORT = "<Pushgateway host port>"
WIFI_PASSWORD = "<your password>"
WIFI_SSID = "<your SSID>"


def connect_to_wifi(ssid, password):
    """ Connect to WiFi network
    """

    wifi = network.WLAN(network.STA_IF)
    wifi.active(True)
    wifi.connect(ssid, password)

    while not wifi.isconnected():
        print("Trying to connect to WiFi network...")
        utime.sleep(1)

    print("Connected to WiFi network.")


def read_temperature(sensor):
    """ Read temperature from sensor and convert to Celsius degrees

    The temperature sensor measures the Vbe voltage of a biased bipolar diode, connected to the fifth ADC channel
    Typically, Vbe = 0.706V at 27 degrees C, with a slope of -1.721mV (0.001721) per degree.

    See: https://datasheets.raspberrypi.org/pico/raspberry-pi-pico-python-sdk.pdf
    """

    conversion_factor = 3.3 / 65535
    reading = sensor.read_u16() * conversion_factor
    temperature = 27 - (reading - 0.706) / 0.001721

    return temperature


def post_temperature(host, port, temperature):
    """ Post temperature to Prometheus gateway
    """

    url = f"http://{host}:{port}/metrics/job/temperature/instance/pico"
    data = f"temperature {temperature}\n"
    try:
        urequests.post(url, data=data)
    except Exception as e:
        print("Failed to post temperature:", e)


def main():
    """ Main function
    """

    connect_to_wifi(WIFI_SSID, WIFI_PASSWORD)
    sensor_temp = machine.ADC(4)

    while True:
        temperature = read_temperature(sensor_temp)
        print(temperature)
        post_temperature(GATEWAY_HOST, GATEWAY_PORT, temperature)
        utime.sleep(15)
        gc.collect()


if __name__ == "__main__":
    main()