memcache_use_advanced_pool = True doesn't work when use oslo.cache

[wangxiyuan]

Env: keystonemiddleware master, oslo.cache master

now keystonemiddleware use oslo.cache for memcache pool.
But when set memcache_use_advanced_pool = True for the service, an error will happen.

use Cinde for example, Error Log:

  [None req-fb207801-3c94-4ecf-a493-fefdf5158c2f None None] Caught error: <type 'exceptions.TypeError'> __init__() takes exactly 3 arguments (2 given): TypeErro
  Traceback (most recent call last):
    File "/opt/stack/cinder/cinder/api/middleware/fault.py", line 85, in __call__
      return req.get_response(self.application)
    File "/usr/local/lib/python2.7/dist-packages/webob/request.py", line 1327, in send
      application, catch_exc_info=False)
    File "/usr/local/lib/python2.7/dist-packages/webob/request.py", line 1291, in call_application
      app_iter = application(self.environ, start_response)
    File "/usr/local/lib/python2.7/dist-packages/webob/dec.py", line 145, in __call__
      return resp(environ, start_response)
    File "/usr/local/lib/python2.7/dist-packages/webob/dec.py", line 131, in __call__
      resp = self.call_func(req, *args, **self.kwargs)
    File "/usr/local/lib/python2.7/dist-packages/webob/dec.py", line 196, in call_func
      return self.func(req, *args, **kwargs)
    File "/usr/local/lib/python2.7/dist-packages/osprofiler/web.py", line 108, in __call__
      return request.get_response(self.application)
    File "/usr/local/lib/python2.7/dist-packages/webob/request.py", line 1327, in send
      application, catch_exc_info=False)
    File "/usr/local/lib/python2.7/dist-packages/webob/request.py", line 1291, in call_application
      app_iter = application(self.environ, start_response)
    File "/usr/local/lib/python2.7/dist-packages/webob/dec.py", line 131, in __call__
      resp = self.call_func(req, *args, **self.kwargs)
    File "/usr/local/lib/python2.7/dist-packages/webob/dec.py", line 196, in call_func
      return self.func(req, *args, **kwargs)
    File "/opt/stack/keystonemiddleware/keystonemiddleware/auth_token/__init__.py", line 334, in __call__
      response = self.process_request(req)
    File "/opt/stack/keystonemiddleware/keystonemiddleware/auth_token/__init__.py", line 631, in process_request
      self._token_cache.initialize(request.environ)
    File "/opt/stack/keystonemiddleware/keystonemiddleware/auth_token/_cache.py", line 149, in initialize
      self._cache_pool = self._get_cache_pool(env.get(self._env_cache_name))
    File "/opt/stack/keystonemiddleware/keystonemiddleware/auth_token/_cache.py", line 140, in _get_cache_pool
      **self._memcache_pool_options)
    File "/opt/stack/keystonemiddleware/keystonemiddleware/auth_token/_cache.py", line 96, in __init__
      **kwargs)
  TypeError: __init__() takes exactly 3 arguments (2 given)

How to reproduce:
1. install the newest keystonemiddleware and oslo.cache
2. set memcache_use_advanced_pool = True in cinder.conf in [keystone_auth] section.
3. restart Cinder
4. print command "cinder list"

Expect: cinder will return the volume list
Actual: cinder raise 500 error, the error log is mentioned above.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/542133

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/542133
Committed: https://git.openstack.org/cgit/openstack/keystonemiddleware/commit/?id=ce06c0ce1035964ecf117bd56f769174508dc269
Submitter: Zuul
Branch: master

commit ce06c0ce1035964ecf117bd56f769174508dc269
Author: wangxiyuan <email address hidden>
Date: Thu Feb 8 17:19:28 2018 +0800

    Add arguments for MemcacheClientPool init

    Now keystonemiddleware use oslo.cache to init the
    MemcacheClientPool. The MemcacheClientPool in
    Olso.cache needs (urls, arguments, **kwargs) parameter
    to init, but keystonemiddleware passed only
    (urls, **kwargs). Then it leads the error:
    __init__() takes exactly 3 arguments (2 given)

    This patch fixed this issue.

    Please note that even this error is fixed, set
    "memcache_use_advanced_pool = True" will lead another
    error, see bug #1747565 for the detail. It will be
    fixed in the following patch.

    Closes-bug: #1748160
    Change-Id: I642f959ab8b010207314312a6b6a06a6de23e92c

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/keystonemiddleware 5.0.0 release.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/queens
Review: https://review.openstack.org/583684

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/583684
Committed: https://git.openstack.org/cgit/openstack/keystonemiddleware/commit/?id=c21f7f43eef21f4b78273058b86fc5b9005f1d93
Submitter: Zuul
Branch: stable/queens

commit c21f7f43eef21f4b78273058b86fc5b9005f1d93
Author: wangxiyuan <email address hidden>
Date: Thu Feb 8 17:19:28 2018 +0800

    Add arguments for MemcacheClientPool init

    Now keystonemiddleware use oslo.cache to init the
    MemcacheClientPool. The MemcacheClientPool in
    Olso.cache needs (urls, arguments, **kwargs) parameter
    to init, but keystonemiddleware passed only
    (urls, **kwargs). Then it leads the error:
    __init__() takes exactly 3 arguments (2 given)

    This patch fixed this issue.

    Please note that even this error is fixed, set
    "memcache_use_advanced_pool = True" will lead another
    error, see bug #1747565 for the detail. It will be
    fixed in the following patch.

    Conflicts:
     keystonemiddleware/tests/unit/auth_token/test_cache.py

    Closes-bug: #1748160
    Change-Id: I642f959ab8b010207314312a6b6a06a6de23e92c
    (cherry picked from commit ce06c0ce1035964ecf117bd56f769174508dc269)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/keystonemiddleware 4.22.0 release.