Updates for release class selection

adapters.py

@@ -18,6 +18,7 @@ from __future__ import absolute_import
 from ops.framework import Object
 
 
+# Adapted from charms_openstack.adapters
 class OpenStackOperRelationAdapter(object):
     """
     Base adapter class for all OpenStack related adapters.
@@ -72,6 +73,7 @@ class OpenStackOperRelationAdapter(object):
                             self.relation, name)))(name))
 
 
+# Adapted from charms_openstack.adapters
 class ConfigurationAdapter(object):
     """
     Configuration Adapter which provides python based access
@@ -97,6 +99,7 @@ class ConfigurationAdapter(object):
             setattr(self, k, v)
 
 
+# Adapted from charms_openstack.adapters
 class OpenStackRelationAdapters(Object):
     """
     Base adapters class for OpenStack Charms, used to aggregate

ops_openstack.py

@@ -2,6 +2,7 @@ from ops.charm import CharmBase
 from ops.framework import (
     StoredState,
 )
+import ops.model
 
 from charmhelpers.fetch import (
     apt_install,
@@ -16,6 +17,27 @@ from ops.model import (
 )
 import charmhelpers.contrib.openstack.utils as os_utils
 import logging
+import copy
+
+# Stolen from charms.ceph
+UCA_CODENAME_MAP = {
+    'icehouse': 'firefly',
+    'juno': 'firefly',
+    'kilo': 'hammer',
+    'liberty': 'hammer',
+    'mitaka': 'jewel',
+    'newton': 'jewel',
+    'ocata': 'jewel',
+    'pike': 'luminous',
+    'queens': 'luminous',
+    'rocky': 'mimic',
+    'stein': 'mimic',
+    'train': 'nautilus',
+    'ussuri': 'octopus',
+}
+
+
+_releases = {}
 logger = logging.getLogger()
 
 class OSBaseCharm(CharmBase):
@@ -89,3 +111,82 @@ class OSBaseCharm(CharmBase):
             charm_func=None)
         self.state.is_paused = False
         self.update_status()
+
+
+def charm_class(cls):
+    _releases[cls.release] =  {'deb': cls}
+
+# Adapted from charms_openstack.charm.core
+def get_charm_class(release=None, package_type='deb', all_releases=None,
+                    *args, **kwargs):
+    """Get an instance of the charm based on the release (or use the
+    default if release is None).
+
+    OS releases are in alphabetical order, so it looks for the first release
+    that is provided if release is None, otherwise it finds the release that is
+    before or equal to the release passed.
+
+    Note that it passes args and kwargs to the class __init__() method.
+
+    :param release: lc string representing release wanted.
+    :param package_type: string representing the package type required
+    :returns: BaseOpenStackCharm() derived class according to cls.releases
+    """
+    if not all_releases:
+        all_releases = os_utils.OPENSTACK_RELEASES
+    if len(_releases.keys()) == 0:
+        raise RuntimeError(
+            "No derived BaseOpenStackCharm() classes registered")
+    # Note that this relies on OS releases being in alphabetical order
+    known_releases = sorted(_releases.keys())
+    cls = None
+    if release is None:
+        # take the latest version of the charm if no release is passed.
+        cls = _releases[known_releases[-1]][package_type]
+    else:
+        # check that the release is a valid release
+        if release not in all_releases:
+            raise RuntimeError(
+                "Release {} is not a known OpenStack release?".format(release))
+        release_index = all_releases.index(release)
+        if (release_index <
+                all_releases.index(known_releases[0])):
+            raise RuntimeError(
+                "Release {} is not supported by this charm. Earliest support "
+                "is {} release".format(release, known_releases[0]))
+        else:
+            # try to find the release that is supported.
+            for known_release in reversed(known_releases):
+                if (release_index >=
+                        all_releases.index(known_release) and
+                        package_type in _releases[known_release]):
+                    cls = _releases[known_release][package_type]
+                    break
+    if cls is None:
+        raise RuntimeError("Release {} is not supported".format(release))
+    return cls
+
+# Adapted from charms_openstack.charm.core
+def get_charm_instance(release=None, package_type='deb', all_releases=None,
+                       *args, **kwargs):
+    return get_charm_class(
+        release=release,
+        package_type=package_type,
+        all_releases=all_releases,
+        *args, **kwargs)(release=release, *args, **kwargs)
+
+def get_charm_class_for_release():
+    _origin = None
+    current_model = ops.model.ModelBackend()
+    config = current_model.config_get()
+    if 'source' in config:
+        _origin = config['source']
+    elif 'openstack-origin' in config:
+        _origin = config['openstack-origin']
+    else:
+        _origin = 'distro'
+    target_releae = os_utils.get_os_codename_install_source(_origin)
+    # Check for a cepch charm match first:
+    ceph_release = UCA_CODENAME_MAP[target_releae]
+    releases = sorted(list(set(UCA_CODENAME_MAP.values())))
+    return get_charm_class(release=ceph_release, all_releases=releases)