Python script to read sensor data from the Enviro+ hat installed in a Raspberry Pi. Using the python libraries to read the raw data, requests library for posting the jsonified data with POST requests and the ST7735 library to update the small LED display whenever a request is done.

enviroSensors.py

#!/usr/bin/python

# Utility di base
import os
import time
import datetime

# Loggare su file
import logging
logging.basicConfig(
    level=logging.INFO,
    filename='/home/fieel/sensorStation.log',
    filemode='a',
    format='%(asctime)s :: %(name)s %(process)d-%(levelname)s - %(message)s')

# Per fare le richieste POST
import requests

## Per interagire con i sensori tramite l'Enviro+ hat
# Temp, humidity and pressure
from bme280 import BME280
try:
    from smbus2 import SMBus
except ImportError:
    from smbus import SMBus
bus = SMBus(1)
bme280 = BME280(i2c_dev=bus)
# Lux & Proximity
try:
    # Transitional fix for breaking change in LTR559
    from ltr559 import LTR559
    ltr559 = LTR559()
except ImportError:
    import ltr559
# Gas
from enviroplus import gas
# Particulate
#from pms5003 import PMS5003
#pms5003 = PMS5003()

# Costanti
API_ENDPOINT = 'http://web.server/iot/enviro/'

# Per manipolare il minidisplay LED 160 x 80
import ST7735
from PIL import Image, ImageDraw, ImageFont
disp = ST7735.ST7735( # Setup display
    port=0,
    cs=1,
    dc=9,
    backlight=12,
    rotation=270,
    spi_speed_hz=10000000
)
disp.begin()

WIDTH = disp.width
HEIGHT = disp.height

# LCD reset e scritta loading
img = Image.new('RGB', (WIDTH, HEIGHT), color=(0,0,0))
draw = ImageDraw.Draw(img)
font_size = 12
font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", font_size)
colour = (250, 250, 250)
temp_message = "Updating data..."
x = 40
y = 35
draw.text((x, y), temp_message, font=font, fill=colour)
disp.display(img)

# Log init
logging.info("Reading new data from sensors...")

# #########################################
# Leggere dati dai sensori nell'hat Enviro+
# #########################################
# Il sensore bme280 bisogna leggerlo qualche volta
# se no ritorna sempre lo stesso valore
counter = 0
compensazione = 3
while counter < 3:
    temperature = bme280.get_temperature() - compensazione
    humidity = bme280.get_humidity()
    pressure = bme280.get_pressure()
    time.sleep(1)
    counter = counter + 1;

lux = ltr559.get_lux()
proximity = ltr559.get_proximity()
gasReadings = gas.read_all() # Required before reading singular values
gas_reducing = gasReadings.reducing
gas_oxidising = gasReadings.oxidising
gas_nh3 = gasReadings.nh3
#try:
#    particulateReadings = pms5003.read() # Same as for gas readings
#    print(particulateReadings)
#    particulate25 = particulateReadings.pm_ug_per_m3(2.5)
#    particulate10 = particulateReadings.pm_ug_per_m3(10)
#except:
#    particulate10 = 0
#    particulate25 = 0

jsonData = {
    'temperature': temperature,
    'humidity': humidity,
    'pressure': pressure,
    'lux': lux,
    'proximity': proximity,
    'gas_reducing': gas_reducing,
    'gas_oxidising': gas_oxidising,
    'gas_nh3': gas_nh3
}

logging.info("POST request to " + API_ENDPOINT  + " start...")

# Costruzione chiamata POST
headers = {
    "Content-Type": "application/json; charset=utf-8",
}
# Salvataggio risultato
postResponse = requests.post(
    API_ENDPOINT,
    headers = headers,
    json = jsonData
)

print("Response code:", postResponse.status_code)

# Debug risultato
if postResponse.status_code == 200:

    logging.info('POST success! Response: ' + postResponse.text)
    print('POST Success! Response: ', postResponse.text)

    # LCD pulizia
    img = Image.new('RGB', (WIDTH, HEIGHT), color=(0,0,0))
    draw = ImageDraw.Draw(img)

    # LCD update risultato
    font_size = 11
    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", font_size)
    colour = (250, 250, 250)
    last_sync_date = "Sync: " + datetime.datetime.now().strftime("%d.%m.%Y %H:%M:%S")
    temperature_text = "{:.2f} C  | {:.2f}% | {:.2f} hPa".format(temperature, humidity, pressure)
    luxprox_text = "lux: {:.2f}, prox: {:.2f} ".format(lux, proximity)
    gas_text1 = "redu: {:.2f}, nh3 {:.2f} ".format(gas_reducing, gas_nh3)
    gas_text2 = "oxi: {:.2f} ".format(gas_oxidising)
    result_text = "OK"

    x = 140
    y = 66
    draw.text((x, y), result_text, font=font, fill=(0, 250, 0))

    x = 0
    y = 0
    draw.text((x, y), last_sync_date, font=font, fill=(250,160,160))

    x = 0
    y = 16
    draw.text((x, y), temperature_text, font=font, fill=(160,250,160))

    x = 0
    y = 32
    draw.text((x, y), luxprox_text, font=font, fill=(160,160,250))

    x = 0
    y = 48
    draw.text((x, y), gas_text1, font=font, fill=(100,100,100))

    x = 0
    y = 64
    draw.text((x, y), gas_text2, font=font, fill=(100,100,100))

    disp.display(img)

else:

    logging.error('POST error! Info: ' + postResponse.text + ' | ' +  postResponse.headers)
    print('POST Not Found. Response:', postResponse.text)
    print('HEADERS: ', postResponse.headers)
    print('content: ', postResponse.content)

  # LCD pulizia
    img = Image.new('RGB', (WIDTH, HEIGHT), color=(0,0,0))
    draw = ImageDraw.Draw(img)

    # LCD update risultato
    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", 12)
    result_text = "ERROR " + str(postResponse.status_code)
    metadatadate = postResponse.headers['Date']
    metadata1 = 'Length: ' + postResponse.headers['Content-Length'] + ",    Type: " + postResponse.headers['Content-Type']
    metadata2 = postResponse.headers['Connection'] + " / " + postResponse.headers['Server']
    error_content = postResponse.text

    x = 48
    y = 10
    draw.text((x, y), result_text, font=font, fill=(250, 0, 0))

    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", 8)
    x = 5
    y = 25
    draw.text((x, y), metadatadate, font=font, fill=(150, 150, 150))

    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", 8)
    x = 5
    y = 35
    draw.text((x, y), metadata1, font=font, fill=(150, 150, 150))


    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", 7)
    x = 50
    y = 1
    draw.text((x, y), metadata2, font=font, fill=(150, 150, 150))


# 'Connection': 'keep-alive', 'Server': 'nginx

    font = ImageFont.truetype("/usr/share/fonts/truetype/lato/Lato-Bold.ttf", 7)
    x = 5
    y = 45
    draw.text((x, y), error_content, font=font, fill=(100, 100, 100))

    disp.display(img)