1 files changed, 94 insertions, 0 deletions
diff --git a/keystone/openstack/common/version.py b/keystone/openstack/common/version.py
new file mode 100644
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+++ b/keystone/openstack/common/version.py
@@ -0,0 +1,94 @@
+
+#    Copyright 2012 OpenStack LLC
+#    Copyright 2012-2013 Hewlett-Packard Development Company, L.P.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Utilities for consuming the version from pkg_resources.
+"""
+
+import pkg_resources
+
+
+class VersionInfo(object):
+
+    def __init__(self, package):
+        """Object that understands versioning for a package
+        :param package: name of the python package, such as glance, or
+                        python-glanceclient
+        """
+        self.package = package
+        self.release = None
+        self.version = None
+        self._cached_version = None
+
+    def __str__(self):
+        """Make the VersionInfo object behave like a string."""
+        return self.version_string()
+
+    def __repr__(self):
+        """Include the name."""
+        return "VersionInfo(%s:%s)" % (self.package, self.version_string())
+
+    def _get_version_from_pkg_resources(self):
+        """Get the version of the package from the pkg_resources record
+        associated with the package."""
+        try:
+            requirement = pkg_resources.Requirement.parse(self.package)
+            provider = pkg_resources.get_provider(requirement)
+            return provider.version
+        except pkg_resources.DistributionNotFound:
+            # The most likely cause for this is running tests in a tree
+            # produced from a tarball where the package itself has not been
+            # installed into anything. Revert to setup-time logic.
+            from keystone.openstack.common import setup
+            return setup.get_version(self.package)
+
+    def release_string(self):
+        """Return the full version of the package including suffixes indicating
+        VCS status.
+        """
+        if self.release is None:
+            self.release = self._get_version_from_pkg_resources()
+
+        return self.release
+
+    def version_string(self):
+        """Return the short version minus any alpha/beta tags."""
+        if self.version is None:
+            parts = []
+            for part in self.release_string().split('.'):
+                if part[0].isdigit():
+                    parts.append(part)
+                else:
+                    break
+            self.version = ".".join(parts)
+
+        return self.version
+
+    # Compatibility functions
+    canonical_version_string = version_string
+    version_string_with_vcs = release_string
+
+    def cached_version_string(self, prefix=""):
+        """Generate an object which will expand in a string context to
+        the results of version_string(). We do this so that don't
+        call into pkg_resources every time we start up a program when
+        passing version information into the CONF constructor, but
+        rather only do the calculation when and if a version is requested
+        """
+        if not self._cached_version:
+            self._cached_version = "%s%s" % (prefix,
+                                             self.version_string())
+        return self._cached_version