Add history metadata for container builds

This commit adds the history section in contianerconfig. With it
'author', 'created_by' and 'comment' can be customized. In addition
'created' is always included with the image creation date time.
'created_by' entry is set to 'KIWI __version__' by default if nothing
is provided.

Fixes #852

kiwi/container/oci.py

@@ -52,7 +52,12 @@ class ContainerImageOCI(object):
                 'expose_ports': ['80', '42'],
                 'volumes': ['/var/log', '/tmp'],
                 'environment': {'PATH': '/bin'},
-                'labels': {'name': 'value'}
+                'labels': {'name': 'value'},
+                'history': {
+                    'created_by': 'some explanation here',
+                    'comment': 'some comment here',
+                    'author': 'tux'
+                }
             }
     """
     def __init__(self, root_dir, custom_args=None):

kiwi/defaults.py

@@ -25,7 +25,10 @@
 
 # project
 from .path import Path
-from .version import __githash__
+from .version import (
+    __githash__,
+    __version__
+)
 
 
 class Defaults(object):
@@ -1173,6 +1176,17 @@ def get_default_container_subcommand(self):
         """
         return ['/bin/bash']
 
+    @classmethod
+    def get_default_container_created_by(self):
+        """
+        Provides the default 'created by' history entry for containers.
+
+        :return: the specific kiwi version used for the build
+
+        :rtype: str
+        """
+        return 'KIWI {0}'.format(__version__)
+
     @classmethod
     def set_python_default_encoding_to_utf8(self):
         """

kiwi/oci_tools/base.py

@@ -17,6 +17,7 @@
 #
 import os
 from tempfile import mkdtemp
+from datetime import datetime
 
 # project
 from kiwi.path import Path
@@ -51,6 +52,9 @@ def __init__(self, container_tag, container_dir=None):
         self.container_name = ':'.join(
             [self.container_dir, self.container_tag]
         )
+        self.creation_date = datetime.utcnow().strftime(
+            '%Y-%m-%dT%H:%M:%S+00:00'
+        )
 
     def init_layout(self, base_image=False):
         """
@@ -81,7 +85,6 @@ def repack(self, oci_root_dir):
         Implementation in specialized tool class
 
         :param string oci_root_dir: root data directory
-        :param string container_name: custom container_dir:tag specifier
         """
         raise NotImplementedError
 

kiwi/oci_tools/umoci.py

@@ -15,11 +15,11 @@
 # You should have received a copy of the GNU General Public License
 # along with kiwi.  If not, see <http://www.gnu.org/licenses/>
 #
-from datetime import datetime
 
 # project
 from kiwi.oci_tools.base import OCIBase
 from kiwi.command import Command
+from kiwi.defaults import Defaults
 
 
 class OCIUmoci(OCIBase):
@@ -70,8 +70,16 @@ def repack(self, oci_root_dir):
 
         :param string oci_root_dir: root data directory
         """
+        history_args = [
+            '--history.created', self.creation_date,
+            '--history.created_by',
+            Defaults.get_default_container_created_by(),
+            '--history.comment', 'umoci repack'
+        ]
         Command.run(
-            ['umoci', 'repack', '--image', self.container_name, oci_root_dir]
+            ['umoci', 'repack', ] + history_args + [
+                '--image', self.container_name, oci_root_dir
+            ]
         )
 
     def add_tag(self, tag_name):
@@ -99,10 +107,9 @@ def set_config(self, oci_config):
             [
                 'umoci', 'config'
             ] + config_args + [
+                '--history.created', self.creation_date,
                 '--image', self.container_name,
-                '--created', datetime.utcnow().strftime(
-                    '%Y-%m-%dT%H:%M:%S+00:00'
-                )
+                '--created', self.creation_date
             ]
         )
 
@@ -168,8 +175,27 @@ def _process_oci_config_to_arguments(self, oci_config):
                     name, oci_config['labels'][name]
                 ))
 
+        arguments.extend(self._process_oci_history_to_arguments(oci_config))
         return arguments
 
+    @classmethod
+    def _process_oci_history_to_arguments(self, oci_config):
+        history_args = []
+        if 'history' in oci_config:
+            if 'comment' in oci_config['history']:
+                history_args.append('--history.comment={0}'.format(
+                    oci_config['history']['comment']
+                ))
+            if 'created_by' in oci_config['history']:
+                history_args.append('--history.created_by={0}'.format(
+                    oci_config['history']['created_by']
+                ))
+            if 'author' in oci_config['history']:
+                history_args.append('--history.author={0}'.format(
+                    oci_config['history']['author']
+                ))
+        return history_args
+
     def garbage_collect(self):
         """
         Cleanup unused data from operations