Extract temporary AWS credentials that an EC2 instance has assumed.

extract-aws-creds.py

import sys
import json
import urllib


def print_creds(iam_role_name):
    '''
    Print out the current AWS credentials that this EC2 instance            
    has been assigned, for a IAM role it has assumed.
    Note that credentials are rotated frequently
    '''
    url_prefix="http://169.254.169.254/latest/meta-data/iam/security-credentials/"
    data = urllib.urlopen(url_prefix + iam_role_name).read()
    creds = json.loads(data)
    print "AWS_ACCESS_KEY_ID=" + creds["AccessKeyId"]
    print "AWS_SECRET_ACCESS_KEY=" + creds["SecretAccessKey"]


if __name__ == "__main__":
    iam_role_name = "dev-support"
    if len(sys.argv) > 1:
        iam_role_name=sys.argv[1]
    print_creds(iam_role_name)