shadow_updater.py for Lambda function 'MoveRobot'

shadow_updater.py

# shadow_updater.py for Lambda function 'MoveRobot'
# Updates the AWS IOT Shadow for the robot
# Shijaz Abdulla - www.awsomenow.com

import os
import time
import json

import boto3

# Get the environment variables so we know where/how to update
clientId = os.environ.get('AWS_IOT_MQTT_CLIENT_ID')
thingName = os.environ.get("AWS_IOT_THING_NAME")
host = os.environ.get("AWS_IOT_MQTT_HOST")
port = os.environ.get("AWS_IOT_MQTT_PORT_UPDATE")

# Updates the device shadow
def update_shadow(new_value_dict):
    topic = "$aws/things/{}/shadow/update".format(thingName)
    payload_dict = {
        "state": {
            "desired" : new_value_dict
        }
    }
    JSON_payload = json.dumps(payload_dict)
    shadow_client = boto3.client('iot-data', 'eu-west-1')
    response = shadow_client.update_thing_shadow(thingName=thingName,
                                                 payload=JSON_payload)
    res_payload = json.loads(response['payload'].read().decode('utf-8'))
    print("Move: {0}".format(res_payload.get("state").get("desired").get("move_direction")))