Note: This function access IoT Data Plane directly, not through the usual MQTT protocol. Useful to simulate an IoT device / sensor using Lambda

MockupIoTDeviceLambda.py

import json
import boto3
import random

MAX_TEMP = 42
MIN_TEMP = 36

def lambda_handler(event, context):
    client = boto3.client('iot-data')
    
    temp = round(random.uniform(MIN_TEMP, MAX_TEMP), 2)
    
    payload = {
        'temperature': temp
    }
    response = client.publish(
        topic='test/topic',
        qos=0,
        payload=json.dumps(payload)
    )
    
    return response