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Hello again. This is the sixth blog post based on the following table.

HCP IoT Showcase using Sphero
Part 1: Overview
Part 2: Controlling Sphero using Raspberry Pi and Xbox 360 controller
Part 3: Maze Setup (Hardware)
Part 4: Unit Test (Gathering & Sending Data)
Part 5: Unit Test (MQTT)
Part 6: Integration Test
Part 7: XS Application
Part 8: UI

This blog explains the highlighted section in the overall architecture below.

Now we integrate all tests into one. So, gathered sensor data will be published via MQTT and sent to IoT Services simultaneously.

For this, SAP Korea team merged (Part 4) and (Part 5) then slightly modified the code as below.
# all configuration settings come from
import config
except ImportError:
print("Please copy to and configure appropriately !"); exit();
import RPi.GPIO as GPIO
import sys
import paho.mqtt.client as mqtt
import time
import random
import paho.mqtt.publish as pubmosq
# init RPi GPIO
GPIO.setup(4, GPIO.IN)
GPIO.setup(5, GPIO.IN)
GPIO.setup(6, GPIO.IN)
GPIO.setup(7, GPIO.IN)
GPIO.setup(8, GPIO.IN)
GPIO.setup(9, GPIO.IN)
GPIO.setup(10, GPIO.IN)
GPIO.setup(11, GPIO.IN)
GPIO.setup(12, GPIO.IN)
GPIO.setup(13, GPIO.IN)
GPIO.setup(14, GPIO.IN)
GPIO.setup(15, GPIO.IN)
GPIO.setup(16, GPIO.IN)
GPIO.setup(17, GPIO.IN)
GPIO.setup(18, GPIO.IN)
GPIO.setup(19, GPIO.IN)
# === START === values set from the file ===
my_endpoint = "iotmms" + config.hcp_account_id + config.hcp_landscape_host
my_endpoint_certificate = config.endpoint_certificate
my_device_id = config.device_id
my_client_id = my_device_id
my_username = my_device_id
my_password = config.oauth_credentials_for_device
my_message_type_upstream = config.message_type_id_From_device
# === END ===== values set from the file ===
my_endpoint_url_path = "/"
# for upstream communication
my_publish_topic = "iot/data/" + my_device_id
# for downstream communication
my_subscription_topic = "iot/push/" + my_device_id
is_connected = False
def on_connect(mqttc, obj, flags, rc):
print("on_connect - rc: " + str(rc))
global is_connected
is_connected = True
# you can use the push API (e.g. also from the built-in sample UI) to send to the device
def on_message(mqttc, obj, msg):
print("on_message - " + msg.topic + " " + str(msg.qos) + " " + str(msg.payload))
def on_publish(mqttc, obj, message_id):
print("on_publish - message_id: " + str(message_id))
def on_subscribe(mqttc, obj, message_id, granted_qos):
print("on_subscribe - message_id: " + str(message_id) + " / qos: " + str(granted_qos))
def on_log(mqttc, obj, level, string):
mqttc = mqtt.Client(client_id=my_client_id, transport='websockets')
mqttc.on_message = on_message
mqttc.on_connect = on_connect
mqttc.on_publish = on_publish
mqttc.on_subscribe = on_subscribe
mqttc.username_pw_set(my_username, my_password)
mqttc.connect(my_endpoint, 443, 60)
# you can use the push API (e.g. also from the built-in sample UI) to send to the device
mqttc.subscribe(my_subscription_topic, 0)
while 1==1:
if is_connected == True:
timestamp = int(time.time())
oSensor_data_4 = GPIO.input(4)
oSensor_data_5 = GPIO.input(5)
oSensor_data_6 = GPIO.input(6)
oSensor_data_7 = GPIO.input(7)
oSensor_data_8 = GPIO.input(8)
oSensor_data_9 = GPIO.input(9)
oSensor_data_10 = GPIO.input(10)
oSensor_data_11 = GPIO.input(11)
oSensor_data_12 = GPIO.input(12)
oSensor_data_13 = GPIO.input(13)
oSensor_data_14 = GPIO.input(14)
oSensor_data_15 = GPIO.input(15)
oSensor_data_16 = GPIO.input(16)
oSensor_data_17 = GPIO.input(17)
oSensor_data_18 = GPIO.input(18)
oSensor_data_19 = GPIO.input(19)
oSensor_data = str(oSensor_data_4) + str(oSensor_data_5) + str(oSensor_data_6) + str(oSensor_data_7) + str(oSensor_data_8) + str(oSensor_data_9) + str(oSensor_data_10) + str(oSensor_data_11) + str(oSensor_data_12) + str(oSensor_data_13) + str(oSensor_data_14) + str(oSensor_data_15) + str(oSensor_data_16) + str(oSensor_data_17) + str(oSensor_data_18) + str(oSensor_data_19)
print oSensor_data
# == START ==== fill the payload now - in this example we use the typical IoT Starterkit payload ======
my_mqtt_payload='{"messageType":"' + my_message_type_upstream + '","messages":[{'
my_mqtt_payload=my_mqtt_payload + '"username":"test user", '
my_mqtt_payload=my_mqtt_payload + '"companyname":"SAP", '
my_mqtt_payload=my_mqtt_payload + '"sensordata":"' + str(oSensor_data) + '", '
my_mqtt_payload=my_mqtt_payload + '"timestamp":' + str(timestamp)
my_mqtt_payload=my_mqtt_payload + '}]}'
# == END ====== fill the payload now - in this example we use the typical IoT Starterkit payload ======
pubmosq.single("/xyz", oSensor_data, hostname="")
mqttc.publish(my_publish_topic, my_mqtt_payload, qos=0)
print("still waiting for connection")

As you can see in line 70, publishing interval is 5 seconds but you can change it if needed. And in line 102, the topic name is /xyz and I just used my Raspberry Pi's IP to connect Mosquitto on it.

Before running this Python code, please check everything is ready for testing as below.

Similar to my previous blog, 3 clients (MQTTLens, Python and Javascript) are ready for subscribing /xyz topic. Then run the code as below.

As I explained, this code will publish messages from GPIO sensors to Mosquitto via /xyz and also send data to HCP IoT Services at the same time.

If everything goes well, you will see following results.

3 clients now get all messages from GPIO.

You will see HCP IoT Services also successfully receive data.

That's it. Thank you for reading this blog. Let me get back to you soon with next posting.