This code walkthrough explains how to publish AstroPiOTA data to the I3 Marketplace.
Use the Connecting an IoT device to the I3 Marketplace. It has step-by-step instructions for signing up to get your API key and to register your product. The guide also contains the I3 Marketplace IP address and port.
Decide how often you will publish data. The AstroPiOTA_publish.py will publish data one time. You can use cron or another scheduler to publish data periodically, for example, every 30 minutes.
#!/usr/bin/python
"""
Purpose: publish AstroPiOTA environment data
"""
Import the Eclipse Paho MQTT Python client library so you can publish sensor data to your subscribers
import paho.mqtt.client as mqtt
In order for your data to be meaningful, you must report the time it was sensed so import time and datetime libraries
import time
import datetime
Data is passed using a json format so import json libraries
import json
In order for SenseHat to sense data, you must import the SenseHat libraries
from sense_hat import SenseHat
This function connects to the broker and prints the status of the connection
def on_connect(client, userdata, flags, rc):
"""printing out result code when connecting with the broker
Args:
client: publisher
userdata:
flags:
rc: result code
Returns:
"""
m="Connected flags"+str(flags)+"\nresult code " +str(rc)+"\nclient1_id "+st r(client)
print(m)
This function prints the sensor data
def on_message(client1, userdata, message):
"""printing out received message
Args:
client1: publisher
userdata:
message: recieved data
Returns:
"""
print("message received " ,str(message.payload.decode("utf-8")))
SenseHat has an 8x8 LED screen. This function sets the pixels to show a smiley face.
def smiley(faceColor, sense):
""" mapping the smiley emoji for the SenseHat LED temperature display """
I = faceColor;
Q = [0,0,70];
i_pixels = [
Q,Q,I,I,I,I,Q,Q,
Q,I,I,I,I,I,I,Q,
I,I,Q,I,I,Q,I,I,
I,I,I,I,I,I,I,I,
I,I,Q,I,I,Q,I,I,
I,I,I,Q,Q,I,I,I,
Q,I,I,I,I,I,I,Q,
Q,Q,I,I,I,I,Q,Q,
];
sense.set_pixels(i_pixels)
This function senses environment data.
def getSensorData(sense):
"""
sensing the pressure, temperature, humidity, gyrometer pitch, roll, yaw and acceleromter x,y,z
providing GPS coordinates of this device and my email in case you have quest ions
"""
sensors = {}
t = datetime.datetime.now()
sensors["timestamp"] = str(t.strftime('%Y%m%d %H:%M'))
sensors["city"] = 'YOUR LOCATION'
sensors["lng"] = 'YOUR LONGITUDE'
sensors["lat"] = 'YOUR LATITUDE'
sensors["device_name"] = "AstroPiOTA"
sensors["temperature"] = str(sense.get_temperature())
sensors["humidity"] = str(sense.get_humidity())
sensors["pressure"] = str(sense.get_pressure())
o = sense.get_orientation()
sensors["pitch"] = str(o["pitch"])
sensors["roll"] = str(o["roll"])
sensors["yaw"] = str(o["yaw"])
a = sense.get_accelerometer_raw()
sensors["x"] = str(a["x"])
sensors["y"] = str(a["y"])
sensors["z"] = str(a["z"])
sensors["device_owner"] = "YOUR_CONTACT_INFO"
return sensors
This function changes colors of the LEDs
def reportWeather(weatherColor, sense):
""" reporting the weather on the SenseHat LED screen """
black = (100,100,100)
sense.show_message("Pi", text_colour=black, back_colour=weatherColor)
smiley(weatherColor, sense)
First, add your username and password. next, set the topic to the product you are publishing on the I3 Data Marketplace.
if __name__ == '__main__':
account = 'YOUR_USERNAME'
pw = 'YOUR_PASSWORD'
topic = "YOUR ASTROPIOTA"
Connect to the broker
try:
pub_client = mqtt.Client(account)
pub_client.on_connect = on_connect
pub_client.on_message = on_message
pub_client.username_pw_set(account, pw)
pub_client.connect('I3 MARKETPLACE IP ADDRESS', PORT)
except Exception as e:
print("Exception", str(e))
Instantiate the SenseHat class and clear the sensors. The payload is the sensor data to be published. Sensor data is formatted using the json format. Print the sensor data.
sense = SenseHat()
sense.clear()
payload = getSensorData(sense)
print(payload)
Payload in json format:
{'humidity': '34.40522003173828',
'roll': '97.56902006720037',
'pressure': '1017.440185546875',
'pitch': '353.91683459592707',
'y': '1.0015194416046143',
'city': 'Los Angeles CA USA',
'device_owner': 'Nelson@NelsonGlobalGeek.com',
'z': '-0.1325657218694687',
'x': '0.10813087970018387',
'timestamp': '20190812 15:27',
'lng': '-118.323411',
'temperature': '42.541664123535156',
'lat': '33.893916',
'yaw': '214.29472998351454',
'device_name': 'AstroPiOTA'}
Publish the sensor data to your subscribers then disconnect.
pub_client.publish(topic, json.dumps(payload))
time.sleep(1)
pub_client.disconnect()
Set the color of the smiley face cool blue, mellow yellow, or red hot
# show temperature emoji
red = (150, 0, 0)
yellow = (150,100,0)
blue = (0,100,150)
# temperature in degrees Celsius
if float(payload["temperature"]) -8 < 5:
reportWeather(blue, sense)
elif float(payload["temperature"])-8 < 40:
reportWeather(yellow,sense)
else:
reportWeather(red,sense)