examples/mqtt-all.py

   1 """
   2 Run mqtt broker on localhost: sudo apt-get install mosquitto mosquitto-clients
   3
   4 Example run: python3 mqtt-all.py --broker 192.168.1.164 --topic enviro
   5 """
   6 #!/usr/bin/env python3
   7
   8 import argparse
   9 import ST7735
  10 import time
  11 from bme280 import BME280
  12 from pms5003 import PMS5003, ReadTimeoutError, SerialTimeoutError
  13 from enviroplus import gas
  14
  15 try:
  16     # Transitional fix for breaking change in LTR559
  17     from ltr559 import LTR559
  18
  19     ltr559 = LTR559()
  20 except ImportError:
  21     import ltr559
  22
  23 from subprocess import PIPE, Popen, check_output
  24 from PIL import Image, ImageDraw, ImageFont
  25 from fonts.ttf import RobotoMedium as UserFont
  26 import json
  27
  28 import paho.mqtt.client as mqtt
  29 import paho.mqtt.publish as publish
  30
  31 try:
  32     from smbus2 import SMBus
  33 except ImportError:
  34     from smbus import SMBus
  35
  36
  37 DEFAULT_MQTT_BROKER_IP = "localhost"
  38 DEFAULT_MQTT_BROKER_PORT = 1883
  39 DEFAULT_MQTT_TOPIC = "enviroplus"
  40 DEFAULT_READ_INTERVAL = 5
  41
  42 # mqtt callbacks
  43 def on_connect(client, userdata, flags, rc):
  44     if rc == 0:
  45         print("connected OK")
  46     else:
  47         print("Bad connection Returned code=", rc)
  48
  49
  50 def on_publish(client, userdata, mid):
  51     print("mid: " + str(mid))
  52
  53
  54 # Read values from BME280 and return as dict
  55 def read_bme280(bme280):
  56     # Compensation factor for temperature
  57     comp_factor = 2.25
  58     values = {}
  59     cpu_temp = get_cpu_temperature()
  60     raw_temp = bme280.get_temperature()  # float
  61     comp_temp = raw_temp - ((cpu_temp - raw_temp) / comp_factor)
  62     values["temperature"] = int(comp_temp)
  63     values["pressure"] = round(
  64         int(bme280.get_pressure() * 100), -1
  65     )  # round to nearest 10
  66     values["humidity"] = int(bme280.get_humidity())
  67     data = gas.read_all()
  68     values["oxidised"] = int(data.oxidising / 1000)
  69     values["reduced"] = int(data.reducing / 1000)
  70     values["nh3"] = int(data.nh3 / 1000)
  71     values["lux"] = int(ltr559.get_lux())
  72     return values
  73
  74
  75 # Read values PMS5003 and return as dict
  76 def read_pms5003(pms5003):
  77     values = {}
  78     try:
  79         pm_values = pms5003.read()  # int
  80         values["pm1"] = pm_values.pm_ug_per_m3(1)
  81         values["pm25"] = pm_values.pm_ug_per_m3(2.5)
  82         values["pm10"] = pm_values.pm_ug_per_m3(10)
  83     except ReadTimeoutError:
  84         pms5003.reset()
  85         pm_values = pms5003.read()
  86         values["pm1"] = pm_values.pm_ug_per_m3(1)
  87         values["pm25"] = pm_values.pm_ug_per_m3(2.5)
  88         values["pm10"] = pm_values.pm_ug_per_m3(10)
  89     return values
  90
  91
  92 # Get CPU temperature to use for compensation
  93 def get_cpu_temperature():
  94     process = Popen(
  95         ["vcgencmd", "measure_temp"], stdout=PIPE, universal_newlines=True
  96     )
  97     output, _error = process.communicate()
  98     return float(output[output.index("=") + 1 : output.rindex("'")])
  99
 100
 101 # Get Raspberry Pi serial number to use as ID
 102 def get_serial_number():
 103     with open("/proc/cpuinfo", "r") as f:
 104         for line in f:
 105             if line[0:6] == "Serial":
 106                 return line.split(":")[1].strip()
 107
 108
 109 # Check for Wi-Fi connection
 110 def check_wifi():
 111     if check_output(["hostname", "-I"]):
 112         return True
 113     else:
 114         return False
 115
 116
 117 # Display Raspberry Pi serial and Wi-Fi status on LCD
 118 def display_status(disp, mqtt_broker):
 119     # Width and height to calculate text position
 120     WIDTH = disp.width
 121     HEIGHT = disp.height
 122     # Text settings
 123     font_size = 12
 124     font = ImageFont.truetype(UserFont, font_size)
 125
 126     wifi_status = "connected" if check_wifi() else "disconnected"
 127     text_colour = (255, 255, 255)
 128     back_colour = (0, 170, 170) if check_wifi() else (85, 15, 15)
 129     device_serial_number = get_serial_number()
 130     message = "{}\nWi-Fi: {}\nmqtt-broker: {}".format(
 131         device_serial_number, wifi_status, mqtt_broker
 132     )
 133     img = Image.new("RGB", (WIDTH, HEIGHT), color=(0, 0, 0))
 134     draw = ImageDraw.Draw(img)
 135     size_x, size_y = draw.textsize(message, font)
 136     x = (WIDTH - size_x) / 2
 137     y = (HEIGHT / 2) - (size_y / 2)
 138     draw.rectangle((0, 0, 160, 80), back_colour)
 139     draw.text((x, y), message, font=font, fill=text_colour)
 140     disp.display(img)
 141
 142
 143 def main():
 144     parser = argparse.ArgumentParser(
 145         description="Publish enviroplus values over mqtt"
 146     )
 147     parser.add_argument(
 148         "--broker",
 149         default=DEFAULT_MQTT_BROKER_IP,
 150         type=str,
 151         help="mqtt broker IP",
 152     )
 153     parser.add_argument(
 154         "--port",
 155         default=DEFAULT_MQTT_BROKER_PORT,
 156         type=int,
 157         help="mqtt broker port",
 158     )
 159     parser.add_argument(
 160         "--topic", default=DEFAULT_MQTT_TOPIC, type=str, help="mqtt topic"
 161     )
 162     parser.add_argument(
 163         "--interval",
 164         default=DEFAULT_READ_INTERVAL,
 165         type=int,
 166         help="the read interval in seconds",
 167     )
 168     args = parser.parse_args()
 169
 170     # Raspberry Pi ID
 171     device_serial_number = get_serial_number()
 172     device_id = "raspi-" + device_serial_number
 173
 174     print(
 175         f"""mqtt-all.py - Reads Enviro plus data and sends over mqtt.
 176
 177     broker: {args.broker}
 178     client_id: {device_id}
 179     port: {args.port}
 180     topic: {args.topic}
 181
 182     Press Ctrl+C to exit!
 183
 184     """
 185     )
 186
 187     mqtt_client = mqtt.Client(client_id=device_id)
 188     mqtt_client.on_connect = on_connect
 189     mqtt_client.on_publish = on_publish
 190     mqtt_client.connect(args.broker, port=args.port)
 191
 192     bus = SMBus(1)
 193
 194     # Create BME280 instance
 195     bme280 = BME280(i2c_dev=bus)
 196
 197     # Create LCD instance
 198     disp = ST7735.ST7735(
 199         port=0, cs=1, dc=9, backlight=12, rotation=270, spi_speed_hz=10000000
 200     )
 201
 202     # Initialize display
 203     disp.begin()
 204
 205     # Try to create PMS5003 instance
 206     HAS_PMS = False
 207     try:
 208         pms5003 = PMS5003()
 209         pm_values = pms5003.read()
 210         HAS_PMS = True
 211         print("PMS5003 sensor is connected")
 212     except SerialTimeoutError:
 213         print("No PMS5003 sensor connected")
 214
 215     # Display Raspberry Pi serial and Wi-Fi status
 216     print("RPi serial: {}".format(device_serial_number))
 217     print("Wi-Fi: {}\n".format("connected" if check_wifi() else "disconnected"))
 218     print("MQTT broker IP: {}".format(args.broker))
 219
 220     # Main loop to read data, display, and send over mqtt
 221     mqtt_client.loop_start()
 222     while True:
 223         try:
 224             values = read_bme280(bme280)
 225             if HAS_PMS:
 226                 pms_values = read_pms5003(pms5003)
 227                 values.update(pms_values)
 228             values["serial"] = device_serial_number
 229             print(values)
 230             mqtt_client.publish(args.topic, json.dumps(values))
 231             display_status(disp, args.broker)
 232             time.sleep(args.interval)
 233         except Exception as e:
 234             print(e)
 235
 236
 237 if __name__ == "__main__":
 238     main()