config: Allow a default refspec to be specified

Also update config file version to 9 due to this format change.

Signed-off-by: Paul Barker <pbarker@konsulko.com>
[Jan: style fix]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

docs/format-changelog.rst

@@ -75,3 +75,13 @@ Added
 
 - ``patches`` property to ``repos`` to be able to apply additional patches to
   the repo.
+
+Version 9
+---------
+
+Added
+~~~~~
+
+- ``defaults`` key can now be used to set a default value for the repository
+  property ``refspec``. This default value will be used if the appropriate
+  property is not defined for a given repository.

docs/userguide.rst

@@ -310,6 +310,22 @@ Configuration reference
       * ``file``: string [required]
           The path to the file relative to the root of the repository.
 
+* ``defaults``: dict [optional]
+    This key can be used to set default values for various properties.
+    This may help you to avoid repeating the same property assignment in
+    multiple places if, for example, you wish to use the same refspec for
+    all repositories.
+
+  * ``repos``: dict [optional]
+      This key can contain default values for some repository properties.
+      If a default value is set for a repository property it may still be
+      overridden by setting the same property to a different value in a given
+      repository.
+
+    * ``refspec``: string [optional]
+        Sets the default ``refspec`` property applied to all repositories that
+        do not override this.
+
 * ``machine``: string [optional]
     Contains the value of the ``MACHINE`` variable that is written into the
     ``local.conf``. Can be overwritten by the ``KAS_MACHINE`` environment

kas/__version__.py

@@ -28,5 +28,5 @@ __copyright__ = 'Copyright (c) Siemens AG, 2017-2018'
 __version__ = '2.1.1'
 
 # Please update docs/format-changelog.rst when changing the file version.
-__file_version__ = 8
+__file_version__ = 9
 __compatible_file_version__ = 1

kas/config.py

@@ -83,12 +83,14 @@ class Config:
             and the `Repo` instances as values.
         """
         repo_config_dict = self._config.get('repos', {})
+        repo_defaults = self._config.get('defaults', {}).get('repos', {})
         repo_dict = {}
         repo_fallback_path = os.path.dirname(self.filenames[0])
         for repo in repo_config_dict:
             repo_config_dict[repo] = repo_config_dict[repo] or {}
             repo_dict[repo] = Repo.factory(repo,
                                            repo_config_dict[repo],
+                                           repo_defaults,
                                            repo_fallback_path)
 
         return repo_dict

kas/configschema.py

@@ -72,6 +72,21 @@ CONFIGSCHEMA = {
                 },
             },
         },
+        'defaults': {
+            'type': 'object',
+            'additionalProperties': False,
+            'properties': {
+                'repos': {
+                    'type': 'object',
+                    'additionalProperties': False,
+                    'properties': {
+                        'refspec': {
+                            'type': 'string',
+                        },
+                    },
+                },
+            },
+        },
         'machine': {
             'type': 'string',
         },

kas/repos.py

@@ -78,7 +78,7 @@ class Repo:
                                 self.path, self._layers)
 
     @staticmethod
-    def factory(name, repo_config, repo_fallback_path):
+    def factory(name, repo_config, repo_defaults, repo_fallback_path):
         """
             Returns a Repo instance depending on params.
         """
@@ -99,7 +99,8 @@ class Repo:
         url = repo_config.get('url', None)
         name = repo_config.get('name', name)
         typ = repo_config.get('type', 'git')
-        refspec = repo_config.get('refspec', None)
+        refspec = repo_config.get('refspec',
+                                  repo_defaults.get('refspec', None))
         path = repo_config.get('path', None)
         disable_operations = False