Refactor: Added name and tag to Image class

The OCI image specification has no guidance on image distribution
as of this patch, but they are considering it. How 'image' and 'tag'
are extracted from different images can be set by the derived class.

- Moved Docker specific properties to DockerImage class
This includes repotag and history
- Moved check for instantiation method from Image class to DockerImage
class
- Added name and tag to the Image class
- Added name and tag setting to the DockerImage class if instantiated
using a repotag
- Added check for name and tag in the tests

The tests work but the main tern executable does not

Signed-off-by: Nisha K <[email protected]>

classes/docker_image.py

@@ -12,17 +12,54 @@
 from utils.constants import manifest_file
 from utils.container import extract_image_metadata
 from utils.dockerfile import directives
+from utils.dockerfile import tag_separator
 
 from .image_layer import ImageLayer
 from .image import Image
 
 
 class DockerImage(Image):
  '''A representation of an image created by Docker
- See image.py for super class's attributes'''
+ See image.py for super class's attributes
+ Docker Image specific attributes:
+ repotags: the list of repotags associated with this image
+ history: a list of commands used to create the filesystem layers
+ '''
  def __init__(self, repotag=None, id=None):
- '''Use superclass's attributes'''
- super().__init__(repotag, id)
+ '''Initialize using repotag and id'''
+ super().__init__(id)
+ self.__repotag = repotag
+ self.__repotags = []
+ self.__history = None
+ if self.repotag is not None:
+ repo_tag_list = self.__repotag.split(tag_separator)
+ self._name = repo_tag_list[0]
+ self._tag = repo_tag_list[1]
+
+ @property
+ def repotag(self):
+ return self.__repotag
+
+ @property
+ def repotags(self):
+ return self.__repotags
+
+ @property
+ def history(self):
+ return self.__history
+
+ def get_image_option(self):
+ '''Check to see which value was used to init the image object
+ Return the value that was used. If neither one was used raise
+ NameError. If both were used return the id'''
+ if self.repotag is not None and self.id is not None:
+ return self.id
+ elif self.repotag is not None:
+ return self.repotag
+ elif self.id is not None:
+ return self.id
+ else:
+ raise NameError("Image object initialized with no repotag or ID")
 
  def get_image_manifest(self):
  '''Assuming that there is a temp folder with a manifest.json of
@@ -92,7 +129,7 @@ def set_layer_created_by(self):
  # the history is ordered according to the order of the layers
  # so the first non-empty history corresponds with the first layer
  index = 0
- for item in self._history:
+ for item in self.__history:
  if 'empty_layer' not in item.keys():
  if 'created_by' in item.keys():
  self._layers[index].created_by = item['created_by']
@@ -110,9 +147,9 @@ def load_image(self):
  print('Failed to extract image')
  self._manifest = self.get_image_manifest()
  self._id = self.get_image_id(self._manifest)
- self._repotags = self.get_image_repotags(self._manifest)
+ self.__repotags = self.get_image_repotags(self._manifest)
  self._config = self.get_image_config(self._manifest)
- self._history = self.get_image_history(self._config)
+ self.__history = self.get_image_history(self._config)
  layer_paths = self.get_image_layers(self._manifest)
  layer_diffs = self.get_diff_ids(self._config)
  while layer_diffs and layer_paths:

classes/image.py

@@ -7,35 +7,26 @@
 class Image(object):
  '''A representation of the image to be analyzed
  attributes:
- repotag: the repotag used to reference the image
  id: this is a unique identifier for the image - for OCI spec this could
- be the digest. For now this is the sha256sum of the config.json in a
- Docker compatible manifest
+ be the digest. For now this is the sha256sum of the config.json
  manifest: the json object representing the image manifest
- repotags: the list of repotags associated with this image
  config: the image config metadata
  layers: list of layer objects in the image
- history: a list of commands used to create the filesystem layers
  methods:
  load_image: this method is to be implemented in the derived classes
  get_layer_diff_ids: returns a list of layer diff ids only
  get_image_option: returns whether the image object was instantiated
  using the repotag or id
  '''
- def __init__(self, repotag=None, id=None):
- '''Either initialize using the repotag or the id'''
- self._repotag = repotag
+ def __init__(self, id=None):
+ '''Either initialize using id'''
  self._id = id
+ self._name = ''
+ self._tag = ''
  self._manifest = {}
- self._repotags = []
  self._config = {}
  self._layers = []
  self._notices = []
- self._history = None
-
- @property
- def repotag(self):
- return self._repotag
 
  @property
  def manifest(self):
@@ -45,10 +36,6 @@ def manifest(self):
  def id(self):
  return self._id
 
- @property
- def repotags(self):
- return self._repotags
-
  @property
  def config(self):
  return self._config
@@ -62,8 +49,12 @@ def notices(self):
  return self._notices
 
  @property
- def history(self):
- return self._history
+ def name(self):
+ return self._name
+
+ @property
+ def tag(self):
+ return self._tag
 
  def add_notice(self, notice):
  self._notices.append(notice)
@@ -72,19 +63,6 @@ def get_layer_diff_ids(self):
  '''Get a list of layer diff ids'''
  return [layer.diff_id for layer in self.layers]
 
- def get_image_option(self):
- '''Check to see which value was used to init the image object
- Return the value that was used. If neither one was used raise
- NameError. If both were used return the id'''
- if self.repotag is not None and self.id is not None:
- return self.id
- elif self.repotag is not None:
- return self.repotag
- elif self.id is not None:
- return self.id
- else:
- raise NameError("Image object initialized with no repotag or ID")
-
  def load_image(self):
  '''Load image metadata
  Currently there is no standard way to do this. For a specific tool,

tests/test_class_docker_image.py

@@ -40,6 +40,8 @@ def tearDown(self):
 
  def testInstance(self):
  self.assertEqual(self.image.repotag, 'debian:jessie')
+ self.assertEqual(self.image.name, 'debian')
+ self.assertEqual(self.image.tag, 'jessie')
  self.assertFalse(self.image.id)
  self.assertFalse(self.image.manifest)
  self.assertFalse(self.image.repotags)