Python Assume Role Example

AssumeRole.py

import boto3

awsaccntid = '123456789123'
targetrole = 'LISTCERTSSTSROLE'

## GET CREDENTIALS
def fn_assume_role(awsaccntid, targetrole):
    client = boto3.client('sts')
    response = client.assume_role(
        RoleArn="arn:aws:iam::" + awsaccntid + ":role/" + targetrole,
        RoleSessionName="AssumeRoleSession1"
    )
    credentials = response['Credentials']
    return credentials

## USING THE ASSUMED ROLE TO DO A BOTO3 THING ##
## In this case, get a list of certificates in the target aws account
def fn_do_boto3_thing(awsaccntid, targetrole):
    credentials = fn_assume_role(awsaccntid, targetrole)
    acm_client = boto3.client(
        'acm',
        aws_access_key_id=credentials['AccessKeyId'],
        aws_secret_access_key=credentials['SecretAccessKey'],
        aws_session_token=credentials['SessionToken']
    )
    response = acm_client.list_certificates(
    )
    return response


fn_do_boto3_thing(awsaccntid)