DynamoDB atomic increment

gistfile1.py

import boto.dynamodb2


def get_connection():
    con = boto.dynamodb2.connect_to_region("eu-west-1")
    return con


def get_new_version(con, package_name):
    item = con.update_item(
        "package-versioncounter",
        {"package": {"S": package_name}},
        {
            "version":
            {"Action": "ADD", "Value": {"N": "1"}}
        }, return_values="ALL_NEW"
    )
    return int(item["Attributes"]["version"]["N"])


def main():
    print get_new_version(get_connection(), "myapp3")

if __name__ == "__main__":
    main()