Creation of Baserock definitions format specification repo

This contains:

- textual description of the Baserock definitions format, and the list
  of changes since version 0, taken from: git://baserock.branchable.com/

- migrations and schemas taken from
  git://git.baserock.org/baserock/baserock/definitions.

1 files changed, 67 insertions, 0 deletions

diff --git a/migrations/007-defaults-in-definitions.py b/migrations/007-defaults-in-definitions.py
new file mode 100755
index 0000000..489baf9
--- /dev/null
+++ b/migrations/007-defaults-in-definitions.py
@@ -0,0 +1,67 @@
+#!/usr/bin/env python
+# Copyright (C) 2015  Codethink Limited
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+'''Migration to Baserock Definitions format version 7.
+
+Definitions version 7 adds a file named DEFAULTS which sets the default
+build commands and default split rules for the set of definitions in that
+repo.
+
+'''
+
+
+import os
+import shutil
+import sys
+import warnings
+
+import migrations
+
+
+TO_VERSION = 7
+
+
+
+try:
+    if migrations.check_definitions_version(TO_VERSION - 1):
+        if os.path.exists('DEFAULTS'):
+            warnings.warn(
+                "DEFAULTS file already exists in these definitions.")
+            valid = False
+        else:
+            shutil.copy(
+                'migrations/007-initial-defaults',
+                'DEFAULTS')
+            valid = True
+
+        if valid:
+            migrations.set_definitions_version(TO_VERSION)
+            sys.stdout.write("Migration completed successfully.\n")
+            sys.exit(0)
+        else:
+            sys.stderr.write(
+                "Migration failed due to one or more warnings.\n")
+            sys.exit(1)
+    else:
+        if not os.path.exists('DEFAULTS'):
+            warnings.warn(
+                "These definitions are marked as version 7 but there is no "
+                "DEFAULTS file.")
+        sys.stdout.write("Nothing to do.\n")
+        sys.exit(0)
+except RuntimeError as e:
+    sys.stderr.write("Error: %s\n" % e.message)
+    sys.exit(1)