Update Object on LDAP module breaks if there is no update

[Jose Castro Leon]

When doing an update of an existing tenant with the same values stored on LDAP (it's done on horizon while modifying a tenant) it crashes on LDAP server. You can see in the debug trace than the update_s is done with an empty modlist.
This operation can not be done on Active Directory servers as backend.

2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] ******************** REQUEST ENVIRON ********************
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] SCRIPT_NAME = /v2.0
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] webob.adhoc_attrs = {'response': <Response at 0x2c69c90 200 OK>}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] REQUEST_METHOD = POST
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] PATH_INFO = /tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] SERVER_PROTOCOL = HTTP/1.0
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] CONTENT_LENGTH = 149
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] HTTP_X_AUTH_TOKEN = keystone_admin_token
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] HTTP_USER_AGENT = python-keystoneclient
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] eventlet.posthooks = []
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] RAW_PATH_INFO = /v2.0//tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] REMOTE_ADDR = 128.142.34.211
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] eventlet.input = <eventlet.wsgi.Input object at 0x2c5df90>
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.url_scheme = https
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] SERVER_PORT = 35357
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.input = <cStringIO.StringI object at 0x1cf01b0>
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] openstack.context = {'token_id': '*******', 'is_admin': True}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] HTTP_HOST = lxbrf17b01.cern.ch:35357
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] HTTPS = on
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.multithread = True
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] openstack.params = {u'tenant': {u'enabled': True, u'description': u'Private Project for user jcastro', u'name': u'jcastro Private', u'id': u'77e43eef529e46278db52ef2d496850b'}}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.version = (1, 0)
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] SERVER_NAME = 128.142.34.211
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] GATEWAY_INTERFACE = CGI/1.1
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.run_once = False
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.errors = <open file '<stderr>', mode 'w' at 0x7f41081241e0>
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] wsgi.multiprocess = False
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] webob.is_body_seekable = True
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] CONTENT_TYPE = application/json
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] HTTP_ACCEPT_ENCODING = gzip, deflate
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi]
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] ******************** REQUEST BODY ********************
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] {"tenant": {"description": "Private Project for user jcastro", "enabled": true, "id": "77e43eef529e46278db52ef2d496850b", "name": "jcastro Private"}}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi]
2013-02-06 15:10:13 DEBUG [routes.middleware] Matched POST /tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [routes.middleware] Route path: '{path_info:.*}', defaults: {'controller': <keystone.contrib.ec2.core.Ec2Extension object at 0x2ab3c10>}
2013-02-06 15:10:13 DEBUG [routes.middleware] Match dict: {'controller': <keystone.contrib.ec2.core.Ec2Extension object at 0x2ab3c10>, 'path_info': '/tenants/77e43eef529e46278db52ef2d496850b'}
2013-02-06 15:10:13 DEBUG [routes.middleware] Matched POST /tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [routes.middleware] Route path: '{path_info:.*}', defaults: {'controller': <keystone.contrib.s3.core.S3Extension object at 0x2aaa8d0>}
2013-02-06 15:10:13 DEBUG [routes.middleware] Match dict: {'controller': <keystone.contrib.s3.core.S3Extension object at 0x2aaa8d0>, 'path_info': '/tenants/77e43eef529e46278db52ef2d496850b'}
2013-02-06 15:10:13 DEBUG [routes.middleware] Matched POST /tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [routes.middleware] Route path: '{path_info:.*}', defaults: {'controller': <keystone.contrib.admin_crud.core.CrudExtension object at 0x2aa36d0>}
2013-02-06 15:10:13 DEBUG [routes.middleware] Match dict: {'controller': <keystone.contrib.admin_crud.core.CrudExtension object at 0x2aa36d0>, 'path_info': '/tenants/77e43eef529e46278db52ef2d496850b'}
2013-02-06 15:10:13 DEBUG [routes.middleware] Matched POST /tenants/77e43eef529e46278db52ef2d496850b
2013-02-06 15:10:13 DEBUG [routes.middleware] Route path: '/tenants/{tenant_id}', defaults: {'action': u'update_tenant', 'controller': <keystone.identity.core.TenantController object at 0x2b2dcd0>}
2013-02-06 15:10:13 DEBUG [routes.middleware] Match dict: {'action': u'update_tenant', 'tenant_id': u'77e43eef529e46278db52ef2d496850b', 'controller': <keystone.identity.core.TenantController object at 0x2b2dcd0>}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] arg_dict: {'tenant_id': u'77e43eef529e46278db52ef2d496850b'}
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP init: url=ldaps://cerndc.cern.ch
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP bind: dn=CN=svckeyad,OU=Users,OU=Organic Units,DC=cern,DC=ch
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP search: dn=cn=77e43eef529e46278db52ef2d496850b,OU=Tenants,OU=Agile,DC=cern,DC=ch, scope=0, query=(objectClass=groupOfNames), attrs=['cn', 'extensionName', 'ou', 'description']
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP init: url=*******
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP bind: *******
2013-02-06 15:10:13 DEBUG [keystone.common.ldap.core] LDAP modify: dn=cn=77e43eef529e46278db52ef2d496850b,OU=Tenants,OU=Agile,DC=cern,DC=ch, modlist=[]
2013-02-06 15:10:13 ERROR [root] {'info': '00000057: LdapErr: DSID-0C090B73, comment: Error in attribute conversion operation, data 0, v1772', 'desc': 'Server is unwilling to perform'}
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/keystone/common/wsgi.py", line 204, in __call__
    result = method(context, **params)
  File "/usr/lib/python2.6/site-packages/keystone/identity/core.py", line 405, in update_tenant
    context, tenant_id, tenant)
  File "/usr/lib/python2.6/site-packages/keystone/common/manager.py", line 47, in _wrapper
    return f(*args, **kw)
  File "/usr/lib/python2.6/site-packages/keystone/identity/backends/ldap/core.py", line 224, in update_tenant
    return self.tenant.update(tenant_id, tenant)
  File "/usr/lib/python2.6/site-packages/keystone/identity/backends/ldap/core.py", line 623, in update
    return super(TenantApi, self).update(id, values, old_obj)
  File "/usr/lib/python2.6/site-packages/keystone/common/ldap/core.py", line 326, in update
    conn.modify_s(self._id_to_dn(id), modlist)
  File "/usr/lib/python2.6/site-packages/keystone/common/ldap/core.py", line 433, in modify_s
    return self.conn.modify_s(dn, ldap_modlist)
  File "/usr/lib64/python2.6/site-packages/ldap/ldapobject.py", line 336, in modify_s
    return self.result(msgid,all=1,timeout=self.timeout)
  File "/usr/lib64/python2.6/site-packages/ldap/ldapobject.py", line 436, in result
    res_type,res_data,res_msgid = self.result2(msgid,all,timeout)
  File "/usr/lib64/python2.6/site-packages/ldap/ldapobject.py", line 440, in result2
    res_type, res_data, res_msgid, srv_ctrls = self.result3(msgid,all,timeout)
  File "/usr/lib64/python2.6/site-packages/ldap/ldapobject.py", line 446, in result3
    ldap_result = self._ldap_call(self._l.result3,msgid,all,timeout)
  File "/usr/lib64/python2.6/site-packages/ldap/ldapobject.py", line 96, in _ldap_call
    result = func(*args,**kwargs)
UNWILLING_TO_PERFORM: {'info': '00000057: LdapErr: DSID-0C090B73, comment: Error in attribute conversion operation, data 0, v1772', 'desc': 'Server is unwilling to perform'}
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] ******************** RESPONSE HEADERS ********************
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] Vary = X-Auth-Token
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] Content-Type = application/json
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] Content-Length = 295
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi]
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] ******************** RESPONSE BODY ********************
2013-02-06 15:10:13 DEBUG [keystone.common.wsgi] {"error": {"message": "An unexpected error prevented the server from fulfilling your request. {'info': '00000057: LdapErr: DSID-0C090B73, comment: Error in attribute conversion operation, data 0, v1772', 'desc': 'Server is unwilling to perform'}", "code": 500, "title": "Internal Server Error"}}
2013-02-06 15:10:13 DEBUG [eventlet.wsgi.server] 128.142.34.211 - - [06/Feb/2013 15:10:13] "POST /v2.0//tenants/77e43eef529e46278db52ef2d496850b HTTP/1.1" 500 443 0.037246

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/21322

[Jose Castro Leon (jose-castro-leon)]

It could be also applied to any object in LDAP (Users, Projects, Roles and Groups)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/21322
Committed: http://github.com/openstack/keystone/commit/2930a289773c8c6124971bed66216db91d48c70d
Submitter: Jenkins
Branch: master

commit 2930a289773c8c6124971bed66216db91d48c70d
Author: Jose Castro Leon <email address hidden>
Date: Wed Feb 6 16:36:15 2013 +0100

    Tenant update on LDAP breaks if there is no update to apply

    Fixes bug 1117362

    Change-Id: Ia47f8a7cd38dcaaceafed39cbdd837ba9a67969f