Added Glance lister

* Added a default strategy to list public images in glance
* Also added basic code to do auth

cachemonkey/auth.py

@@ -0,0 +1,75 @@
+# Copyright 2014 Rackspace Hosting
+# All Rights Reserved.
+#
+#    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.
+
+from keystoneclient.v2_0 import client
+from oslo.config import cfg
+
+from cachemonkey.openstack.common import log as logging
+
+LOG = logging.getLogger(__name__)
+CONF = cfg.CONF
+
+opts = [
+
+    cfg.StrOpt('url', help='Auth system endpoint URL'),
+    cfg.StrOpt('username', help='Username for auth'),
+    cfg.StrOpt('password', help='Password for auth'),
+    cfg.StrOpt('region', help='Region'),
+]
+
+CONF.register_opts(opts, group='auth')
+
+
+class Client(object):
+
+    def __init__(self):
+        url, username, password, region = self._config()
+        self.keystoneclient = client.Client(auth_url=url, username=username,
+                                            password=password,
+                                            region_name=region)
+
+    def auth(self):
+        if not self.keystoneclient.authenticate():
+            raise Exception('Failed to auth with keystoneclient')
+
+    @property
+    def catalog(self):
+        return self.keystoneclient.service_catalog
+
+    @property
+    def token(self):
+        return self.keystoneclient.auth_token
+
+    def _config(self):
+        # check for presence of required config options
+        url = CONF.auth.url
+        if not url:
+            raise ValueError('Missing required url for auth')
+
+        username = CONF.auth.username
+        if not username:
+            raise ValueError('Missing required username for auth')
+
+        password = CONF.auth.password
+        if not password:
+            raise ValueError('Missing required password for auth')
+
+        # the region scopes the catalog object for easier endpoint
+        # identification
+        region = CONF.auth.region
+        if not region:
+            raise ValueError('Missing required region for auth')
+
+        return url, username, password, region

cachemonkey/cacher.py

@@ -37,3 +37,5 @@ class Cacher(object):
 
     def cache(self):
         images = self.lister.images()
+        for image in images:
+            LOG.debug(image)

cachemonkey/lister/glance.py

@@ -13,9 +13,48 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import glanceclient
+from oslo.config import cfg
+
+from cachemonkey import auth
+from cachemonkey.openstack.common import log as logging
+
+LOG = logging.getLogger(__name__)
+CONF = cfg.CONF
+
+opt = cfg.StrOpt('endpoint', help='Glance endpoint (override catalog)')
+CONF.register_opt(opt, group='glance')
+
 
 class GlanceLister(object):
 
+    def __init__(self):
+        self.authclient = auth.Client()
+        self.authclient.auth()
+        endpoint = self._endpoint()
+
+        api_version = 2
+        token = self.authclient.token
+        self.client = glanceclient.Client(api_version, endpoint, token=token)
+
     def images(self):
+        LOG.debug('Fetching image list')
         # list images to be cached.
-        pass
+        images = self.client.images.list()
+        return images
+
+    def _endpoint(self):
+        # if an endpoint is provided via config, prefer that
+        if CONF.glance.endpoint:
+            return CONF.glance.endpoint
+
+        # fallback to getting the glance endpoint from the service catalog
+        catalog = self.authclient.catalog
+        image_endpoints = catalog.get_endpoints()['image']
+
+        LOG.debug('Image endpoints: %s' % image_endpoints)
+        if len(image_endpoints) > 1:
+            LOG.warn('Expected a single image endpoint, but there are %d' %
+                     len(image_endpoints))
+
+        return image_endpoints[0]['publicURL']

requirements.txt

@@ -4,3 +4,5 @@ iso8601>=0.1.9
 oslo.config>=1.2.0
 pbr>=0.6,!=0.7,<1.0
 posix_ipc
+python-glanceclient>=0.9.0
+python-keystoneclient>=0.9.0