#!/usr/bin/env python3

import logging

import time

from subprocess import check_output

import requests

import st7735

from bme280 import BME280

from fonts.ttf import RobotoMedium as UserFont

from PIL import Image, ImageDraw, ImageFont

from pms5003 import PMS5003, ChecksumMismatchError, ReadTimeoutError

from smbus2 import SMBus

logging.basicConfig(

format="%(asctime)s.%(msecs)03d %(levelname)-8s %(message)s",

level=logging.INFO,

datefmt="%Y-%m-%d %H:%M:%S")

logging.info("""sensorcommunity.py - Reads temperature, pressure, humidity,

PM2.5, and PM10 from Enviro plus and sends data to Sensor.Community,

the citizen science air quality project.

Note: you'll need to register with Sensor.Community at:

https://devices.sensor.community/ and enter your Raspberry Pi

serial number that's displayed on the Enviro plus LCD along

with the other details before the data appears on the

Sensor.Community map.

Press Ctrl+C to exit!

""")

bus = SMBus(1)

# Create BME280 instance

bme280 = BME280(i2c_dev=bus)

# Create LCD instance

disp = st7735.ST7735(

port=0,

cs=1,

dc="GPIO9",

backlight="GPIO12",

rotation=270,

spi_speed_hz=10000000

)

# Initialize display

disp.begin()

# Create PMS5003 instance

pms5003 = PMS5003()

# Read values from BME280 and PMS5003 and return as dict

def read_values():

values = {}

cpu_temp = get_cpu_temperature()

raw_temp = bme280.get_temperature()

comp_temp = raw_temp - ((cpu_temp - raw_temp) / comp_factor)

values["temperature"] = f"{comp_temp:.2f}"

values["pressure"] = f"{bme280.get_pressure() * 100:.2f}"

values["humidity"] = f"{bme280.get_humidity():.2f}"

try:

pm_values = pms5003.read()

values["P2"] = str(pm_values.pm_ug_per_m3(2.5))

values["P1"] = str(pm_values.pm_ug_per_m3(10))

except(ReadTimeoutError, ChecksumMismatchError):

logging.info("Failed to read PMS5003. Resetting and retrying.")

pms5003.reset()

pm_values = pms5003.read()

values["P2"] = str(pm_values.pm_ug_per_m3(2.5))

values["P1"] = str(pm_values.pm_ug_per_m3(10))

return values

# Get the temperature of the CPU for compensation

def get_cpu_temperature():

with open("/sys/class/thermal/thermal_zone0/temp", "r") as f:

temp = f.read()

temp = int(temp) / 1000.0

return temp

# Get Raspberry Pi serial number to use as ID

def get_serial_number():

with open("/proc/cpuinfo", "r") as f:

for line in f:

if line.startswith("Serial"):

return line.split(":")[1].strip()

# Check for Wi-Fi connection

def check_wifi():

if check_output(["hostname", "-I"]):

return True

else:

return False

# Display Raspberry Pi serial and Wi-Fi status on LCD

def display_status():

wifi_status = "connected" if check_wifi() else "disconnected"

text_colour = (255, 255, 255)

back_colour = (0, 170, 170) if check_wifi() else (85, 15, 15)

id = get_serial_number()

message = f"{id}\nWi-Fi: {wifi_status}"

img = Image.new("RGB", (WIDTH, HEIGHT), color=(0, 0, 0))

draw = ImageDraw.Draw(img)

x1, y1, x2, y2 = font.getbbox(message)

size_x = x2 - x1

size_y = y2 - y1

x = (WIDTH - size_x) / 2

y = (HEIGHT / 2) - (size_y / 2)

draw.rectangle((0, 0, 160, 80), back_colour)

draw.text((x, y), message, font=font, fill=text_colour)

disp.display(img)

def send_to_sensorcommunity(values, id):

pm_values = dict(i for i in values.items() if i[0].startswith("P"))

temp_values = dict(i for i in values.items() if not i[0].startswith("P"))

pm_values_json = [{"value_type": key, "value": val} for key, val in pm_values.items()]

temp_values_json = [{"value_type": key, "value": val} for key, val in temp_values.items()]

resp_pm = None

resp_bmp = None

try:

resp_pm = requests.post(

"https://api.sensor.community/v1/push-sensor-data/",

json={

"software_version": "enviro-plus 1.0.0",

"sensordatavalues": pm_values_json

},

headers={

"X-PIN": "1",

"X-Sensor": id,

"Content-Type": "application/json",

"cache-control": "no-cache"

},

timeout=5

)

except requests.exceptions.ConnectionError as e:

logging.warning(f"Sensor.Community PM Connection Error: {e}")

except requests.exceptions.Timeout as e:

logging.warning(f"Sensor.Community PM Timeout Error: {e}")

except requests.exceptions.RequestException as e:

logging.warning(f"Sensor.Community PM Request Error: {e}")

try:

resp_bmp = requests.post(

"https://api.sensor.community/v1/push-sensor-data/",

json={

"software_version": "enviro-plus 1.0.0",

"sensordatavalues": temp_values_json

},

headers={

"X-PIN": "11",

"X-Sensor": id,

"Content-Type": "application/json",

"cache-control": "no-cache"

},

timeout=5

)

except requests.exceptions.ConnectionError as e:

logging.warning(f"Sensor.Community Climate Connection Error: {e}")

except requests.exceptions.Timeout as e:

logging.warning(f"Sensor.Community Climate Timeout Error: {e}")

except requests.exceptions.RequestException as e:

logging.warning(f"Sensor.Community Climate Request Error: {e}")

if resp_pm is not None and resp_bmp is not None:

if resp_pm.ok and resp_bmp.ok:

return True

else:

logging.warning(f"Sensor.Community Error. PM: {resp_pm.reason}, Climate: {resp_bmp.reason}")

return False

else:

return False

# Compensation factor for temperature

comp_factor = 2.25

# Raspberry Pi ID to send to Sensor.Community

id = "raspi-" + get_serial_number()

# Width and height to calculate text position

WIDTH = disp.width

HEIGHT = disp.height

# Text settings

font_size = 16

font = ImageFont.truetype(UserFont, font_size)

# Log Raspberry Pi serial and Wi-Fi status

logging.info(f"Raspberry Pi serial: {get_serial_number()}")

wifi_status = "connected" if check_wifi() else "disconnected"

logging.info(f"Wi-Fi: {wifi_status}\n")

time_since_update = 0

update_time = time.time()

# Main loop to read data, display, and send to Sensor.Community

while True:

try:

values = read_values()

time_since_update = time.time() - update_time

if time_since_update > 145:

logging.info(values)

update_time = time.time()

if send_to_sensorcommunity(values, id):

logging.info("Sensor.Community Response: OK")

else:

logging.warning("Sensor.Community Response: Failed")

display_status()

except Exception as e:

logging.warning(f"Main Loop Exception: {e}")