From 3bc265281fd7cdaa9656f5c4c5f9325c4d1a37e1 Mon Sep 17 00:00:00 2001
From: Brian Waldon <bcwaldon@gmail.com>
Date: Fri, 16 Nov 2012 14:27:00 -0800
Subject: [PATCH] Refactor where store drivers are initialized

The call to create_stores was happening in the v1 and v2 API
controllers. This moves that call and the verification that
the default_store exists into the necessary binaries.

Fixes bug 1039727.

Change-Id: I36542fd9b1d536d6266898766317abe110bb71a2
---
 bin/glance-api                         |  4 +++
 bin/glance-cache-prefetcher            |  6 ++++-
 bin/glance-scrubber                    | 27 ++++++++++++--------
 glance/api/v1/images.py                | 35 +++-----------------------
 glance/api/v2/image_data.py            |  1 -
 glance/api/v2/images.py                |  1 -
 glance/image_cache/prefetcher.py       | 10 ++------
 glance/store/__init__.py               | 15 +++++++++++
 glance/store/scrubber.py               |  2 --
 glance/tests/functional/v1/test_api.py |  2 +-
 glance/tests/unit/base.py              |  3 ---
 glance/tests/unit/test_http_store.py   |  1 -
 12 files changed, 46 insertions(+), 61 deletions(-)

diff --git a/bin/glance-api b/bin/glance-api
index 071bf908f2..97599c6559 100755
--- a/bin/glance-api
+++ b/bin/glance-api
@@ -40,6 +40,7 @@ from glance.common import config
 from glance.common import wsgi
 from glance.common import exception
 from glance.openstack.common import log
+import glance.store
 
 
 def fail(returncode, e):
@@ -52,6 +53,9 @@ if __name__ == '__main__':
         config.parse_args()
         log.setup('glance')
 
+        glance.store.create_stores()
+        glance.store.verify_default_store()
+
         server = wsgi.Server()
         server.start(config.load_paste_app, default_port=9292)
         server.wait()
diff --git a/bin/glance-cache-prefetcher b/bin/glance-cache-prefetcher
index 7948ae9407..9986c928a3 100755
--- a/bin/glance-cache-prefetcher
+++ b/bin/glance-cache-prefetcher
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # vim: tabstop=4 shiftwidth=4 softtabstop=4
 
-# Copyright 2011 OpenStack LLC.
+# Copyright 2011-2012 OpenStack LLC.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -40,6 +40,7 @@ gettext.install('glance', unicode=1)
 from glance.common import config
 from glance.image_cache import prefetcher
 from glance.openstack.common import cfg
+import glance.store
 
 CONF = cfg.CONF
 
@@ -49,6 +50,9 @@ if __name__ == '__main__':
         config.parse_cache_args()
         config.setup_logging()
 
+        glance.store.create_stores()
+        glance.store.verify_default_store()
+
         app = prefetcher.Prefetcher()
         app.run()
     except RuntimeError, e:
diff --git a/bin/glance-scrubber b/bin/glance-scrubber
index 365ead9faf..55a97ed793 100755
--- a/bin/glance-scrubber
+++ b/bin/glance-scrubber
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # vim: tabstop=4 shiftwidth=4 softtabstop=4
 
-# Copyright 2011 OpenStack LLC.
+# Copyright 2011-2012 OpenStack LLC.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -36,27 +36,32 @@ gettext.install('glance', unicode=1)
 
 from glance.common import config
 from glance.openstack.common import cfg
+import glance.store
 from glance.store import scrubber
 
 CONF = cfg.CONF
 
 
 if __name__ == '__main__':
+    CONF.register_cli_opt(
+        cfg.BoolOpt('daemon',
+                    short='D',
+                    default=False,
+                    help='Run as a long-running process. When not '
+                         'specified (the default) run the scrub operation '
+                         'once and then exits. When specified do not exit '
+                         'and run scrub on wakeup_time interval as '
+                         'specified in the config.'))
+    CONF.register_opt(cfg.IntOpt('wakeup_time', default=300))
+
     try:
-        CONF.register_cli_opt(
-            cfg.BoolOpt('daemon',
-                        short='D',
-                        default=False,
-                        help='Run as a long-running process. When not '
-                             'specified (the default) run the scrub operation '
-                             'once and then exits. When specified do not exit '
-                             'and run scrub on wakeup_time interval as '
-                             'specified in the config.'))
-        CONF.register_opt(cfg.IntOpt('wakeup_time', default=300))
 
         config.parse_args()
         config.setup_logging()
 
+        glance.store.create_stores()
+        glance.store.verify_default_store()
+
         app = scrubber.Scrubber()
 
         if CONF.daemon:
diff --git a/glance/api/v1/images.py b/glance/api/v1/images.py
index cd3cf35cfd..d80c2b5fdf 100644
--- a/glance/api/v1/images.py
+++ b/glance/api/v1/images.py
@@ -1,6 +1,6 @@
 # vim: tabstop=4 shiftwidth=4 softtabstop=4
 
-# Copyright 2010 OpenStack LLC.
+# Copyright 2010-2012 OpenStack LLC.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -19,7 +19,6 @@
 /images endpoint for Glance v1 API
 """
 
-import sys
 import traceback
 
 import eventlet
@@ -34,7 +33,6 @@ from webob.exc import (HTTPError,
 from glance.api import common
 from glance.api import policy
 import glance.api.v1
-from glance import context
 from glance.api.v1 import controller
 from glance.api.v1 import filters
 from glance.common import exception
@@ -44,8 +42,7 @@ from glance import notifier
 from glance.openstack.common import cfg
 import glance.openstack.common.log as logging
 from glance import registry
-from glance.store import (create_stores,
-                          get_from_backend,
+from glance.store import (get_from_backend,
                           get_size_from_backend,
                           safe_delete_from_backend,
                           schedule_delayed_delete_from_backend,
@@ -53,6 +50,7 @@ from glance.store import (create_stores,
                           get_store_from_scheme)
 
 
+CONF = cfg.CONF
 LOG = logging.getLogger(__name__)
 SUPPORTED_PARAMS = glance.api.v1.SUPPORTED_PARAMS
 SUPPORTED_FILTERS = glance.api.v1.SUPPORTED_FILTERS
@@ -61,14 +59,6 @@ DISK_FORMATS = ['ami', 'ari', 'aki', 'vhd', 'vmdk', 'raw', 'qcow2', 'vdi',
                 'iso']
 
 
-# Defined at module level due to _is_opt_registered
-# identity check (not equality).
-default_store_opt = cfg.StrOpt('default_store', default='file')
-
-CONF = cfg.CONF
-CONF.register_opt(default_store_opt)
-
-
 def validate_image_meta(req, values):
 
     name = values.get('name')
@@ -126,8 +116,6 @@ class Controller(controller.BaseController):
     """
 
     def __init__(self):
-        create_stores()
-        self.verify_scheme_or_exit(CONF.default_store)
         self.notifier = notifier.Notifier()
         registry.configure_registry_client()
         self.policy = policy.Enforcer()
@@ -885,23 +873,6 @@ class Controller(controller.BaseController):
                                  request=request,
                                  content_type='text/plain')
 
-    def verify_scheme_or_exit(self, scheme):
-        """
-        Verifies availability of the storage backend for the
-        given scheme or exits
-
-        :param scheme: The backend store scheme
-        """
-        try:
-            get_store_from_scheme(context.RequestContext(), scheme)
-        except exception.UnknownScheme:
-            msg = _("Store for scheme %s not found")
-            LOG.error(msg % scheme)
-            # message on stderr will only be visible if started directly via
-            # bin/glance-api, as opposed to being daemonized by glance-control
-            sys.stderr.write(msg % scheme)
-            sys.exit(255)
-
 
 class ImageDeserializer(wsgi.JSONRequestDeserializer):
     """Handles deserialization of specific controller method requests."""
diff --git a/glance/api/v2/image_data.py b/glance/api/v2/image_data.py
index e9083f4088..18b5bb59c8 100644
--- a/glance/api/v2/image_data.py
+++ b/glance/api/v2/image_data.py
@@ -35,7 +35,6 @@ class ImageDataController(object):
         self.db_api = db_api or glance.db.get_api()
         self.db_api.configure_db()
         self.store_api = store_api or glance.store
-        self.store_api.create_stores()
         self.policy = policy_enforcer or policy.Enforcer()
         self.notifier = notifier or glance.notifier.Notifier()
 
diff --git a/glance/api/v2/images.py b/glance/api/v2/images.py
index cac9ce25a1..4887f05143 100644
--- a/glance/api/v2/images.py
+++ b/glance/api/v2/images.py
@@ -48,7 +48,6 @@ class ImagesController(object):
         self.policy = policy_enforcer or policy.Enforcer()
         self.notifier = notifier or glance.notifier.Notifier()
         self.store_api = store_api or glance.store
-        self.store_api.create_stores()
 
     def _enforce(self, req, action):
         """Authorize an action against our policies"""
diff --git a/glance/image_cache/prefetcher.py b/glance/image_cache/prefetcher.py
index dd9081e9c3..3f48ff7cb4 100644
--- a/glance/image_cache/prefetcher.py
+++ b/glance/image_cache/prefetcher.py
@@ -27,12 +27,6 @@ from glance.image_cache import base
 import glance.openstack.common.log as logging
 from glance import registry
 import glance.store
-import glance.store.filesystem
-from glance.store import get_from_backend
-import glance.store.http
-import glance.store.rbd
-import glance.store.s3
-import glance.store.swift
 
 
 LOG = logging.getLogger(__name__)
@@ -41,7 +35,6 @@ LOG = logging.getLogger(__name__)
 class Prefetcher(base.CacheApp):
 
     def __init__(self):
-        glance.store.create_stores()
         super(Prefetcher, self).__init__()
         registry.configure_registry_client()
         registry.configure_registry_admin_creds()
@@ -60,7 +53,8 @@ class Prefetcher(base.CacheApp):
             LOG.warn(_("No metadata found for image '%s'"), image_id)
             return False
 
-        image_data, image_size = get_from_backend(ctx, image_meta['location'])
+        location = image_meta['location']
+        image_data, image_size = glance.store.get_from_backend(ctx, location)
         LOG.debug(_("Caching image '%s'"), image_id)
         self.cache.cache_image_iter(image_id, image_data)
         return True
diff --git a/glance/store/__init__.py b/glance/store/__init__.py
index 2f1828ac30..ff4dd5666a 100644
--- a/glance/store/__init__.py
+++ b/glance/store/__init__.py
@@ -21,6 +21,7 @@ import time
 
 from glance.common import exception
 from glance.common import utils
+import glance.context
 from glance.openstack.common import cfg
 from glance.openstack.common import importutils
 import glance.openstack.common.log as logging
@@ -37,6 +38,10 @@ store_opts = [
                     'glance.store.s3.Store',
                     'glance.store.swift.Store',
                 ]),
+    cfg.StrOpt('default_store', default='file',
+               help=_("Default scheme to use to store image data. The "
+                      "scheme must be registered by one of the stores "
+                      "defined by the 'known_stores' config option.")),
     cfg.StrOpt('scrubber_datadir',
                default='/var/lib/glance/scrubber'),
     cfg.BoolOpt('delayed_delete', default=False),
@@ -168,6 +173,16 @@ def create_stores():
     return store_count
 
 
+def verify_default_store():
+    scheme = cfg.CONF.default_store
+    context = glance.context.RequestContext()
+    try:
+        get_store_from_scheme(context, scheme)
+    except exception.UnknownScheme:
+        msg = _("Store for scheme %s not found") % scheme
+        raise RuntimeError(msg)
+
+
 def get_store_from_scheme(context, scheme):
     """
     Given a scheme, return the appropriate store object
diff --git a/glance/store/scrubber.py b/glance/store/scrubber.py
index 4d9755176d..a07e6ae387 100644
--- a/glance/store/scrubber.py
+++ b/glance/store/scrubber.py
@@ -92,8 +92,6 @@ class Scrubber(object):
 
         utils.safe_mkdirs(self.datadir)
 
-        store.create_stores()
-
     def run(self, pool, event=None):
         now = time.time()
 
diff --git a/glance/tests/functional/v1/test_api.py b/glance/tests/functional/v1/test_api.py
index 02eac4e1ec..ca890b777d 100644
--- a/glance/tests/functional/v1/test_api.py
+++ b/glance/tests/functional/v1/test_api.py
@@ -1240,7 +1240,7 @@ class TestApi(functional.FunctionalTest):
         # ensure that the API server fails to launch
         self.start_server(self.api_server,
                           expect_launch=False,
-                          expected_exitcode=255,
+                          expected_exitcode=1,
                           **self.__dict__.copy())
 
     def _do_test_post_image_content_bad_format(self, format):
diff --git a/glance/tests/unit/base.py b/glance/tests/unit/base.py
index 6d2a9ff115..abc0981932 100644
--- a/glance/tests/unit/base.py
+++ b/glance/tests/unit/base.py
@@ -23,9 +23,6 @@ import stubout
 
 from glance.openstack.common import cfg
 from glance import store
-# NOTE(ameade): this import is necessary. Since we override a cfg opt it
-# registers we must have that opt loaded.
-from glance.store import filesystem
 from glance.store import location
 from glance.tests import stubs
 from glance.tests import utils as test_utils
diff --git a/glance/tests/unit/test_http_store.py b/glance/tests/unit/test_http_store.py
index 25b356de58..43ea833f52 100644
--- a/glance/tests/unit/test_http_store.py
+++ b/glance/tests/unit/test_http_store.py
@@ -17,7 +17,6 @@
 
 import stubout
 
-from glance.common import config
 from glance.common import exception
 from glance import context
 from glance.db.sqlalchemy import api as db_api