s3_download.py

import boto3
from botocore.exceptions import NoCredentialsError, ClientError


def main(args, settings):
    arg_archive_file = args.get("<archive_file>", None)
    aws_s3_bucket_name = settings.get("AWS_S3_BUCKET_NAME")
    aws_s3_bucket_key = settings.get("AWS_S3_BUCKET_KEY")
    aws_default_region = settings.get("AWS_DEFAULT_REGION")
    aws_access_key_id = settings.get("AWS_ACCESS_KEY_ID")
    aws_secret_access_key = settings.get("AWS_SECRET_ACCESS_KEY")
    aws_endpoint_url = settings.get("AWS_ENDPOINT_URL")

    session = boto3.Session(
        aws_access_key_id=aws_access_key_id, aws_secret_access_key=aws_secret_access_key, region_name=aws_default_region
    )

    s3 = session.resource(service_name="s3", endpoint_url=aws_endpoint_url)

    s3_path = "{0}/{1}".format(aws_s3_bucket_key, arg_archive_file)
    s3_object = s3.Object(aws_s3_bucket_name, s3_path)

    try:
        # .read() left off on purpose, tarfile.open() takes care of that part
        s3_data = s3_object.get()["Body"]
        print("Download from S3 was successful")
    except ClientError as e:
        if e.response["Error"]["Code"] == "NoSuchKey":
            print("Error: Key {0} does not exist in bucket {1}".format(s3_path, aws_s3_bucket_name))
            return False
        raise e
    except NoCredentialsError:
        print("Credentials not available")
        return False

    return s3_data