def setup(dockerfile=None):
'''Any initial setup'''
# load the cache
cache.load()
# load dockerfile if present
if dockerfile:
docker.load_docker_commands(dockerfile)
def setup(dockerfile=None, image_tag_string=None):
'''Any initial setup'''
# generate random names for image, container, and tag
general.initialize_names()
# load the cache
cache.load()
# load dockerfile if present
if dockerfile:
docker.load_docker_commands(dockerfile)
# check if the docker image is present
if image_tag_string:
if not container.check_image(image_tag_string):
logger.fatal(errors.cannot_find_image.format(
imagetag=image_tag_string))
sys.exit()
# create temporary working directory
if not os.path.exists(constants.temp_folder):
os.mkdir(constants.temp_folder)
# set up folders for rootfs operations
rootfs.set_up()
def get_base_obj(base_image_tag):
'''Get a list of layers with their associated packages:
1. Check if the base image exists on the host machine
2. Get the layers
3. For each layer check if there is a list of packages associated
with it in the cache
4. If there are no packages return a list of empty layer objects'''
obj_list = []
if not check_base_image(base_image_tag):
# the base image cannot be found locally nor remotely
# at this point there is no context for Tern to use so raise an
# exception to exit gracefully
logger.error(base_image_not_found)
sys.exit(1)
else:
cache.load()
# get the history with diff ids
# tuples look like this: (history command, diff_id)
layer_history = get_layer_history(get_image_tag_string(base_image_tag))
for layer_tuple in layer_history:
layer_obj = get_layer_obj(layer_tuple[1])
obj_list.append(layer_obj)
return obj_list