def prepare_device_package()

in setup/lambda-custom-resource/prepare_dev_package_cr.py [0:0]

• 44 lines of code
• 6 McCabe index (conditional complexity)

def prepare_device_package(event, context):
    """Prepares the edge device package in a lambda function and uploads it to the S3 bucket"""

    # create a new thing group
    thing_group_arn = None
    agent_pkg_bucket = 'sagemaker-edge-release-store-us-west-2-linux-x64'
    agent_config_package_prefix = 'edge-device-configuration/agent/config.tgz'

    # check if edge agent package has already been built
    try:
        s3_client.download_file(Bucket=BUCKET_NAME, Key=agent_config_package_prefix, Filename='/tmp/dump')
        LOGGER.info('The agent configuration package was already built! Skipping...')
        quit()
    except ClientError as e:
        pass
    
    # Create a new thing group if not found yet
    try:
        thing_group_arn = iot_client.describe_thing_group(thingGroupName=iot_thing_group_name)['thingGroupArn']
        LOGGER.info("Thing group found")
    except iot_client.exceptions.ResourceNotFoundException as e:
        LOGGER.info("Creating a new thing group")
        thing_group_arn = iot_client.create_thing_group(thingGroupName=iot_thing_group_name)['thingGroupArn']

    LOGGER.info("Creating the directory structure for the agent")
    # create a structure for the agent files
    os.makedirs(LOCAL_DIR_PREFIX + 'agent/certificates/root', exist_ok=True)
    os.makedirs(LOCAL_DIR_PREFIX + 'agent/certificates/iot', exist_ok=True)
    os.makedirs(LOCAL_DIR_PREFIX + 'agent/logs', exist_ok=True)
    os.makedirs(LOCAL_DIR_PREFIX + 'agent/model', exist_ok=True)
    os.makedirs(LOCAL_DIR_PREFIX + 'agent/conf', exist_ok=True)
    
    LOGGER.info("Downloading root certificate and agent binary")
    # then get some root certificates
    resp = http.request('GET', 'https://www.amazontrust.com/repository/AmazonRootCA1.pem')
    with open(LOCAL_DIR_PREFIX + 'agent/certificates/iot/AmazonRootCA1.pem', 'w') as c:
        c.write(resp.data.decode('utf-8'))
    
    # this certificate validates the edge manage package
    s3_client.download_file(
        Bucket=agent_pkg_bucket, 
        Key='Certificates/%s/%s.pem' % (AWS_REGION, AWS_REGION), 
        Filename=LOCAL_DIR_PREFIX + 'agent/certificates/root/%s.pem' % AWS_REGION
    )

    LOGGER.info("Adjusting file permissions of pem files")
    # adjust the permissions of the files
    os.chmod(LOCAL_DIR_PREFIX + 'agent/certificates/iot/AmazonRootCA1.pem', stat.S_IRUSR|stat.S_IRGRP)
    os.chmod(LOCAL_DIR_PREFIX + 'agent/certificates/root/%s.pem' % AWS_REGION, stat.S_IRUSR|stat.S_IRGRP)
    
    LOGGER.info("Processing the agent...")
    setup_agent(iot_thing_group_name, thing_group_arn )
    
    LOGGER.info("Creating the final package...")
    with io.BytesIO() as f:
        with tarfile.open(fileobj=f, mode='w:gz') as tar:
            tar.add(LOCAL_DIR_PREFIX + 'agent', 'agent', recursive=True)
        f.seek(0)
        LOGGER.info("Uploading to S3")
        s3_client.upload_fileobj(f, Bucket=BUCKET_NAME, Key=agent_config_package_prefix)
    LOGGER.info("Done!")