#!/usr/bin/env python3

import requests

import ST7735

import time

from bme280 import BME280

from pms5003 import PMS5003, ReadTimeoutError, ChecksumMismatchError

from subprocess import PIPE, Popen, check_output

from PIL import Image, ImageDraw, ImageFont

from fonts.ttf import RobotoMedium as UserFont

try:

from smbus2 import SMBus

except ImportError:

from smbus import SMBus

import logging

logging.basicConfig(

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

level=logging.INFO,

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

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

#PM2.5, and PM10 from Enviro plus and sends data to Luftdaten,

#the citizen science air quality project.

#Note: you'll need to register with Luftdaten at:

#https://meine.luftdaten.info/ 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

#Luftdaten 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=9,

backlight=12,

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"] = "{:.2f}".format(comp_temp)

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

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

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. Reseting 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 CPU temperature to use for compensation

def get_cpu_temperature():

process = Popen(['vcgencmd', 'measure_temp'], stdout=PIPE, universal_newlines=True)

output, _error = process.communicate()

return float(output[output.index('=') + 1:output.rindex("'")])

# 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[0:6] == '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 = "{}\nWi-Fi: {}".format(id, wifi_status)

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

draw = ImageDraw.Draw(img)

size_x, size_y = draw.textsize(message, font)

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_luftdaten(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.luftdaten.info/v1/push-sensor-data/",

json={

"software_version": "enviro-plus 0.0.1",

"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('Luftdaten PM Connection Error: {}'.format(e))

except requests.exceptions.Timeout as e:

logging.warning('Luftdaten PM Timeout Error: {}'.format(e))

except requests.exceptions.RequestException as e:

logging.warning('Luftdaten PM Request Error: {}'.format(e))

try:

resp_bmp = requests.post(

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

json={

"software_version": "enviro-plus 0.0.1",

"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('Luftdaten Climate Connection Error: {}'.format(e))

except requests.exceptions.Timeout as e:

logging.warning('Luftdaten Climate Timeout Error: {}'.format(e))

except requests.exceptions.RequestException as e:

logging.warning('Luftdaten Climate Request Error: {}'.format(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('Luftdaten Error. PM: {}, Climate: {}'.format(resp_pm.reason, resp_bmp.reason))

return False

else:

return False

# Compensation factor for temperature

comp_factor = 2.25

# Raspberry Pi ID to send to Luftdaten

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("Raspberry Pi serial: {}".format(get_serial_number()))

logging.info("Wi-Fi: {}\n".format("connected" if check_wifi() else "disconnected"))

time_since_update = 0

update_time = time.time()

# Main loop to read data, display, and send to Luftdaten

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_luftdaten(values, id):

logging.info("Luftdaten Response: OK")

else:

logging.warning("Luftdaten Response: Failed")

display_status()

except Exception as e:

logging.warning('Main Loop Exception: {}'.format(e))