Add additional multi-layer complex squashing test

test/registry/protocol_fixtures.py

@@ -37,6 +37,45 @@ def sized_images():
   ]
 
 
+@pytest.fixture(scope="session")
+def multi_layer_images():
+  """ Returns complex images (with sizes) for push and pull testing. """
+  # Note: order is from base layer down to leaf.
+  layer1_bytes = layer_bytes_for_contents('layer 1 contents', mode='', other_files={
+    'file1': 'from-layer-1',
+  })
+
+  layer2_bytes = layer_bytes_for_contents('layer 2 contents', mode='', other_files={
+    'file2': 'from-layer-2',
+  })
+
+  layer3_bytes = layer_bytes_for_contents('layer 3 contents', mode='', other_files={
+    'file1': 'from-layer-3',
+    'file3': 'from-layer-3',
+  })
+
+  layer4_bytes = layer_bytes_for_contents('layer 4 contents', mode='', other_files={
+    'file3': 'from-layer-4',
+  })
+
+  layer5_bytes = layer_bytes_for_contents('layer 5 contents', mode='', other_files={
+    'file4': 'from-layer-5',
+  })
+
+  return [
+    Image(id='layer1', bytes=layer1_bytes, parent_id=None, size=len(layer1_bytes),
+          config={'internal_id': 'layer1'}),
+    Image(id='layer2', bytes=layer2_bytes, parent_id='layer1', size=len(layer2_bytes),
+          config={'internal_id': 'layer2'}),
+    Image(id='layer3', bytes=layer3_bytes, parent_id='layer2', size=len(layer3_bytes),
+          config={'internal_id': 'layer3'}),
+    Image(id='layer4', bytes=layer4_bytes, parent_id='layer3', size=len(layer4_bytes),
+          config={'internal_id': 'layer4'}),
+    Image(id='someid', bytes=layer5_bytes, parent_id='layer4', size=len(layer5_bytes),
+          config={'internal_id': 'layer5'}),
+  ]
+
+
 @pytest.fixture(scope="session")
 def jwk():
   return RSAKey(key=RSA.generate(2048))

test/registry/protocols.py

@@ -14,8 +14,9 @@ PushResult = namedtuple('PushResult', ['checksums', 'manifests', 'headers'])
 PullResult = namedtuple('PullResult', ['manifests', 'image_ids'])
 
 
-def layer_bytes_for_contents(contents, mode='|gz'):
+def layer_bytes_for_contents(contents, mode='|gz', other_files=None):
   layer_data = StringIO()
+  tar_file = tarfile.open(fileobj=layer_data, mode='w' + mode)
 
   def add_file(name, contents):
     tar_file_info = tarfile.TarInfo(name=name)
@@ -23,12 +24,16 @@ def layer_bytes_for_contents(contents, mode='|gz'):
     tar_file_info.size = len(contents)
     tar_file_info.mtime = 1
 
-    tar_file = tarfile.open(fileobj=layer_data, mode='w' + mode)
     tar_file.addfile(tar_file_info, StringIO(contents))
-    tar_file.close()
 
   add_file('contents', contents)
 
+  if other_files is not None:
+    for file_name, file_contents in other_files.iteritems():
+      add_file(file_name, file_contents)
+
+  tar_file.close()
+
   layer_bytes = layer_data.getvalue()
   layer_data.close()
   return layer_bytes

test/registry/registry_tests.py

@@ -930,6 +930,58 @@ def test_squashed_image_disabled_user(pusher, sized_images, liveserver_session,
   assert response.status_code == 403
 
 
+@pytest.mark.parametrize('use_estimates', [
+  False,
+  True,
+])
+def test_multilayer_squashed_images(use_estimates, pusher, multi_layer_images, liveserver_session,
+                                    liveserver, registry_server_executor, app_reloader):
+  """ Test: Pulling of multilayer, complex squashed images. """
+  credentials = ('devtable', 'password')
+
+  # Push an image to download.
+  pusher.push(liveserver_session, 'devtable', 'newrepo', 'latest', multi_layer_images,
+              credentials=credentials)
+
+  if use_estimates:
+    # Clear the uncompressed size stored for the images, to ensure that we estimate instead.
+    for image in multi_layer_images:
+      registry_server_executor.on(liveserver).clear_uncompressed_size(image.id)
+
+  # Pull the squashed version.
+  response = liveserver_session.get('/c1/squash/devtable/newrepo/latest', auth=credentials)
+  tar = tarfile.open(fileobj=StringIO(response.content))
+
+  # Verify the squashed image.
+  expected_image_id = 'cdc6d6c0d07d2cbacfc579e49ce0c256c5084b9b2b16c1b1b0c45f26a12a4ba5'
+  expected_names = ['repositories',
+                    expected_image_id,
+                    '%s/json' % expected_image_id,
+                    '%s/VERSION' % expected_image_id,
+                    '%s/layer.tar' % expected_image_id]
+
+  assert tar.getnames() == expected_names
+
+  # Verify the JSON image data.
+  json_data = (tar.extractfile(tar.getmember('%s/json' % expected_image_id)).read())
+
+  # Ensure the JSON loads and parses.
+  result = json.loads(json_data)
+  assert result['id'] == expected_image_id
+  assert result['config']['internal_id'] == 'layer5'
+
+  # Ensure that squashed layer tar can be opened.
+  tar = tarfile.open(fileobj=tar.extractfile(tar.getmember('%s/layer.tar' % expected_image_id)))
+  assert set(tar.getnames()) == {'contents', 'file1', 'file2', 'file3', 'file4'}
+
+  # Check the contents of various files.
+  assert tar.extractfile('contents').read() == 'layer 5 contents'
+  assert tar.extractfile('file1').read() == 'from-layer-3'
+  assert tar.extractfile('file2').read() == 'from-layer-2'
+  assert tar.extractfile('file3').read() == 'from-layer-4'
+  assert tar.extractfile('file4').read() == 'from-layer-5'
+
+
 @pytest.mark.parametrize('use_estimates', [
   False,
   True,