#------------------------------------------------------------------------------------------------- 
#    Author         : Emertxe (https://emertxe.com) 
#    Date           : Wed 02 Aug 2021 10:00:00 IST
#    Function       : hello_lambda
#    Title          : First Lambda Function
#    Description    : A basic Lambda function in AWS using python
#-------------------------------------------------------------------------------------------------
 
import datetime

def lambda_handler(event, context):
    print ("Hello Lambda")
    print ("The time is", datetime.datetime.now())
    print ("This print is from function", context.function_name)

#------------------------------------------------------------------------------------------------- 
#    Author         : Emertxe (https://emertxe.com) 
#    Date           : Wed 03 Aug 2021 10:00:00 IST
#    Function       : aws_iot_trigger.py
#    Title          : AWS IoT Trigger
#    Description    : A basic Lambda function which is triggered with the help of AWS IoT Core
#-------------------------------------------------------------------------------------------------

import json

def lambda_handler(event, context):
    num1 = event['number1']; 
    num2 = event['number2']; 
    result = num1 + num2; 

    print "The result is", result;

    return {
        "result": result 
    }

#------------------------------------------------------------------------------------------------- 
#    Author         : Emertxe (https://emertxe.com) 
#    Date           : Wed 03 Aug 2021 10:00:00 IST
#    Function       : aws_publish_from_aws.py
#    Title          : Publich from AWS IoT core 
#    Description    : A basic Lambda function which is triggered with the help of AWS IoT Core
#                     and publish back to client application 
#-------------------------------------------------------------------------------------------------

import os
import json
import boto3

# Note: You need to set these environmental variables
ACCESS_KEY=os.environ["ACCESS_KEY"]
SECRET_KEY=os.environ["SECRET_KEY"]
ENDPOINT=os.environ["ENDPOINT"]

def lambda_handler(event, context):
    data_payload = { 
        "Sum": event['number1'] + event['number2']
    }   

    print(data_payload)

    # Create an AWS IoT client 
    data = boto3.client(
        'iot-data',
        endpoint_url=ENDPOINT,
        aws_access_key_id=ACCESS_KEY,
        aws_secret_access_key=SECRET_KEY
    )

    # Publish a simple message to the specified IoT topic
    response = data.publish(
        topic='MyDevice/result',
        qos=1,
        payload=json.dumps(data_payload)
    )

    # Print out the response
    print(response)