openstack/python-keystoneclient
Code Issues Proposed changes

Isolate get_discovery function

Browse Source 
When we get to having version independent identity plugins they need to
be able to share the discovery cache with the session. This function
should therefore be reusable rather than making the cache on the session
public.

DocImpact: Adds a new get_discovery function to identity plugins. This
function is expected to be used by subclasses doing custom URL discovery
rather than users.

Blueprint: version-independant-plugins
Change-Id: I769b4e2cd59a4dd167c4dcd8f14641081f867a71
This commit is contained in:
Jamie Lennox
2014-07-17 16:00:16 +10:00
parent 4b10d11c1a
commit 5d2264051d
1 changed files with 42 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
keystoneclient/auth/identity/base.py
View File

@@ -180,19 +180,50 @@ class BaseIdentityPlugin(base.BaseAuthPlugin):
interface = 'public'
service_catalog = self.get_access(session).service_catalog
sc_url = service_catalog.url_for(service_type=service_type,
endpoint_type=interface,
region_name=region_name,
service_name=service_name)
url = service_catalog.url_for(service_type=service_type,
endpoint_type=interface,
region_name=region_name,
service_name=service_name)
if not version:
# NOTE(jamielennox): This may not be the best thing to default to
# but is here for backwards compatibility. It may be worth
# defaulting to the most recent version.
return sc_url
return url
disc = None
try:
disc = self.get_discovery(session, url)
except (exceptions.DiscoveryFailure,
exceptions.HTTPError,
exceptions.ConnectionError):
# NOTE(jamielennox): Again if we can't contact the server we fall
# back to just returning the URL from the catalog. This may not be
# the best default but we need it for now.
LOG.warn('Failed to contact the endpoint at %s for discovery. '
'Fallback to using that endpoint as the base url.', url)
else:
url = disc.url_for(version)
return url
def get_discovery(self, session, url):
"""Return the discovery object for a URL.
Check the session and the plugin cache to see if we have already
performed discovery on the URL and if so return it, otherwise create
a new discovery object, cache it and return it.
This function is expected to be used by subclasses and should not
be needed by users.
:param Session session: A session object to discover with.
:param str url: The url to lookup.
:raises: DiscoveryFailure if for some reason the lookup fails.
:raises: HttpError An error from an invalid HTTP response.
:return: A discovery object with the results of looking up that URL.
"""
# NOTE(jamielennox): we want to cache endpoints on the session as well
# so that they maintain sharing between auth plugins. Create a cache on
# the session if it doesn't exist already.
@@ -205,24 +236,16 @@ class BaseIdentityPlugin(base.BaseAuthPlugin):
# object and the auth plugin object so that they can be shared and the
# cache is still usable
for cache in (self._endpoint_cache, session_endpoint_cache):
disc = cache.get(sc_url)
disc = cache.get(url)
if disc:
break
else:
try:
disc = _discover.Discover(session, sc_url)
except (exceptions.HTTPError, exceptions.ConnectionError):
LOG.warn('Failed to contact the endpoint at %s for discovery. '
'Fallback to using that endpoint as the '
'base url.', sc_url)
disc = _discover.Discover(session, url)
self._endpoint_cache[url] = disc
session_endpoint_cache[url] = disc
return sc_url
else:
self._endpoint_cache[sc_url] = disc
session_endpoint_cache[sc_url] = disc
return disc.url_for(version)
return disc
@classmethod
def get_options(cls):