Prepare your Raspberry Pi device
Make sure you have free developer account in SAP Cloud Platform
Configure virtual device for Raspberry Pi in SCP
Modify the code
Run the code and check the results

Published November 3, 2017 © Apache-2.0

Weather Station Data from RPi Sense HAT via HTTPS

Sending environmental data from Raspberry Pi's Sense HAT to SAP Cloud Platform IoT Service for Neo using HTTPS protocol.

BeginnerProtip30 minutes3,610

Weather Station Data from RPi Sense HAT via HTTPS

Things used in this project

Hardware components

Raspberry Pi 3 Model B

Raspberry Pi Sense HAT

Software apps and online services

SAP Cloud Platform IoT for the Neo environment

Story

It is one of many examples of different devices supplying environmental sensor data (temperature, humidity) to SAP Cloud Platform (SCP). Here Raspberry Pi 3B device is used with connected Sense Hat. Sensor data will be send synchronously using HTTPS REST protocol.

Prepare your Raspberry Pi device

In this project I am using Raspberry Pi 3B with Sense Hat connected to it. Sense Hat library is usually preinstalled on this model.

The code is executed with Python 3 and is using Requests library available from http://docs.python-requests.org/en/master/

Make sure you have free developer account in SAP Cloud Platform

If you do not, please follow this tutorial first: https://www.sap.com/developer/tutorials/iot-part6-hcp-services.html

Configure virtual device for Raspberry Pi in SCP

Follow the tutorial https://www.sap.com/developer/tutorials/iot-part7-add-device.html and then create a separate virtual device for your raspberry Pi. Instead of "myDevice" you can call it "raspberrypi".

Creare raspberrypi device with device type weatherStation

Note down technical ID of this raspberrypi virtual device and its assigned authorization token. You will need them in the next step.

Modify the code

Modify attached Python code (at the bottom of this page). You will need to add your Message Type ID, Device ID, etc. The lines in particular you will need to modify are the following:

You should modify:

The accountOwner line to add your own SAP Cloud Platform Account User ID which starts with either an S , P , I , D or C .

The msgtypeid is the ID of the message type you created, and not the name of the message type.

The deviceid is the ID of the device you created, not to be confused with the token

The authtoken line contains the token of the device (not the device type!). You received it in the pop-up window after creating your device. But if missed it, then regenerate this token from Device screen once again.

Save the file as scpiot_neo_rpisensehat_http.py

Run the code and check the results

Once you have saved your file run the following command:

python3 scpiot_neo_rpisensehat_http.py

If everything is correct, then you should see output similar to this one. The loop reads and posts values every f and the green arrow flying through HAT's LEDs with every successful post to the SAP Cloud Platform.

Output of the code execution on Raspberry Pi

You can preview received data in the cloud in Message Management Service Cockpit. There is the OData API link to now use this data in your applications!

Default Chart for this device

Press Ctrl+C to stop the execution of the program.

Have a good weather!

scpiot_neo_rpisensehat_http.py

from sense_hat import SenseHat
import requests # http://docs.python-requests.org/en/master/
import time
import sys, platform

accountOwner = '<your account id>'
deviceid = '<device id of your raspberrypi>'
authtoken = '<auth token for your raspberrypi virtual device>'
msgtypeid = '<message type id for the weatherStation>'

hostiotmms = 'iotmms'+accountOwner+'trial.hanatrial.ondemand.com'
apiiotmmsdata = '/com.sap.iotservices.mms/v1/api/http/data/'
url = "https://"+hostiotmms+apiiotmmsdata+deviceid
print("URL: ", url)

sense = SenseHat()
sense.clear()
sense.set_rotation(90)
red = (255, 0, 0)
green = (0, 255, 0)

def readsensors():
	d_tstamp = int(round(time.time()))

	temp = sense.get_temperature()
	d_temp = round(temp, 1)
	#print("Temperature C",temp)

	humidity = sense.get_humidity()
	d_humy = round(humidity, 1)
	#print("Humidity :",humidity)

	pressure = sense.get_pressure()
	d_pres = round(pressure, 1)
	#print("Pressure:",pressure)

	return (d_temp, d_humy, d_pres)

def postiotneo (d_temp, d_humy, d_pres):

	d_tstamp = int(round(time.time()))
	
	s_tstamp = str(d_tstamp)
	s_temp = str(d_temp)
	s_humy = str(d_humy)
	s_pres = str(d_pres)

	payload = "{\"mode\":\"sync\",\"messageType\":\""+msgtypeid+"\",\"messages\":[{\"temperature\":"+s_temp+",\"humidity\":"+s_humy+",\"timestamp\":"+s_tstamp+"}]}"
	headers = {
			'content-type': "application/json",
			'authorization': "Bearer "+authtoken,
			'cache-control': "no-cache"
			}

	print(payload)

	response = requests.request("POST", url, data=payload, headers=headers)

	if str(response.status_code)[0:1]=='2':
		sense.show_message("<-", text_colour=green)
	else:
		sense.show_message("O", text_colour=red)
		
	print(response.status_code, response.text)
	# print(response.headers)

	return

try:
	while(True):
		postiotneo(*readsensors())
		time.sleep(5)

except KeyboardInterrupt:
		time.sleep(1)
		print("Have a nice weather!")

Credits

Vitaliy Rudnytskiy [SAP]

1 project • 4 followers

SAP Developer Relations

Weather Station Data from RPi Sense HAT via HTTPS