compose: New module for easy access to compose metadata.

doc/compose.rst

@@ -0,0 +1,15 @@
+==========================================
+compose -- Easy access to compose metadata
+==========================================
+
+.. automodule:: productmd.compose
+
+
+
+
+Classes
+=======
+
+.. autoclass:: productmd.compose.Compose
+    :members:
+    :inherited-members:

doc/conf.py

@@ -217,6 +217,8 @@
      [u'Daniel Mach <dmach@redhat.com>'], 7),
 
     # modules
+    ('compose', 'compose', u'productmd Documentation',
+     [u'Daniel Mach <dmach@redhat.com>'], 1),
     ('composeinfo', 'composeinfo', u'productmd Documentation',
      [u'Daniel Mach <dmach@redhat.com>'], 1),
     ('discinfo', 'discinfo', u'productmd Documentation',

doc/index.rst

@@ -18,6 +18,7 @@ Python modules:
     :maxdepth: 2
 
     common
+    compose
     composeinfo
     discinfo
     images

productmd/compose.py

@@ -0,0 +1,116 @@
+# -*- coding: utf-8 -*-
+
+
+# Copyright (C) 2015  Red Hat, Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+
+"""
+This module provides Compose class that provides easy access
+to ComposeInfo, Rpms and Images in compose metadata.
+
+Example::
+
+  import productmd.compose
+  compose = productmd.compose.Compose("/path/to/compose")
+
+  # then you can access compose metadata via following properties:
+  compose.info
+  compose.images
+  compose.rpms
+"""
+
+
+import os
+
+import productmd.composeinfo
+import productmd.images
+import productmd.rpms
+
+
+__all__ = (
+    "Compose",
+)
+
+
+class Compose(object):
+    """
+    This class provides easy access to compose metadata.
+    """
+
+    def __init__(self, compose_path):
+        self.compose_path = compose_path
+        compose_path = os.path.join(compose_path, "compose")
+        if os.path.isdir(compose_path):
+            self.compose_path = compose_path
+
+        self._composeinfo = None
+        self._images = None
+        self._rpms = None
+
+    def _find_metadata_file(self, paths):
+        for i in paths:
+            path = os.path.join(self.compose_path, i)
+            if os.path.exists(path):
+                return path
+        return None
+
+    @property
+    def info(self):
+        """(:class:`productmd.composeinfo.ComposeInfo`) -- Compose metadata"""
+        if self._composeinfo is not None:
+            return self._composeinfo
+
+        composeinfo = productmd.composeinfo.ComposeInfo()
+        paths = [
+            "metadata/composeinfo.json",
+        ]
+        path = self._find_metadata_file(paths)
+        composeinfo.load(path)
+        self._composeinfo = composeinfo
+        return self._composeinfo
+
+    @property
+    def images(self):
+        """(:class:`productmd.images.Images`) -- Compose images metadata"""
+        if self._images is not None:
+            return self._images
+
+        images = productmd.images.Images()
+        paths = [
+            "metadata/images.json",
+            "metadata/image-manifest.json",
+        ]
+        path = self._find_metadata_file(paths)
+        images.load(path)
+        self._images = images
+        return self._images
+
+    @property
+    def rpms(self):
+        """(:class:`productmd.rpms.Rpms`) -- Compose RPMs metadata"""
+        if self._rpms is not None:
+            return self._rpms
+
+        rpms = productmd.rpms.Rpms()
+        paths = [
+            "metadata/rpms.json",
+            "metadata/rpm-manifest.json",
+        ]
+        path = self._find_metadata_file(paths)
+        rpms.load(path)
+        self._rpms = rpms
+        return self._rpms