ebsAvailableLambda.py

ebsAvailableLambda.py

import boto3
import json
import time


def lambda_handler(event, context):
    client = boto3.client('ec2')
    documentName = "ebs_available"
    # event['resources'] will return the arn
    for elements in event['resources']:
        arn = str(elements)
        print(arn)
        volumeId = arn[42:63] # getting the volumeId from the arn
        print(volumeId)
        # this sleep function is here to have a wait time
        # while the volume gets attached
        time.sleep(40)
        response = client.describe_volumes(
            VolumeIds=[
                volumeId,
            ],
        )
        for volume in response['Volumes']:
            print(volume)
            for attchmnt in volume['Attachments']:
                print(attchmnt['InstanceId'])
                attchmnt_word = attchmnt['Device'][len(attchmnt['Device'])-1:len(attchmnt['Device'])]
                device = "/dev/xvd"+attchmnt_word
                print(device)
                ssm = boto3.client('ssm')
                # sending command with instanceId, documentnName, documentVersion, comment
                response = ssm.send_command(
                    InstanceIds=[attchmnt['InstanceId']],
                    DocumentName=documentName,
                    DocumentVersion='$LATEST',
                    Comment='ssm.send_command from lambda to make ebs available',
                    # send device to which parameter should be mounted
                    Parameters={
                        'Device': [device],
                    },
                )