--- a/schema.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/schema.py	Thu Jul 23 15:28:41 2009 +0200
@@ -36,7 +36,7 @@
 #  set of meta-relations available for every entity types
 META_RELATIONS_TYPES = set((
     'owned_by', 'created_by', 'is', 'is_instance_of', 'identity',
-    'eid', 'creation_date', 'modification_date', 'has_text',
+    'eid', 'creation_date', 'modification_date', 'has_text', 'cwuri',
     ))
 
 #  set of entity and relation types used to build the schema

--- a/schemas/base.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/schemas/base.py	Thu Jul 23 15:28:41 2009 +0200
@@ -131,6 +131,12 @@
     subject = '*'
     object = 'Datetime'
 
+class cwuri(RelationType):
+    """internal entity uri"""
+    cardinality = '11'
+    subject = '**'
+    object = 'String'
+
 
 class CWProperty(EntityType):
     """used for cubicweb configuration. Once a property has been created you

--- a/server/hooks.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/server/hooks.py	Thu Jul 23 15:28:41 2009 +0200
@@ -33,6 +33,8 @@
         entity['creation_date'] = datetime.now()
     if not 'modification_date' in entity:
         entity['modification_date'] = datetime.now()
+    if not 'cwuri' in entity:
+        entity['cwuri'] = session.base_url() + u'eid/%s' % entity.eid
 
 def setmtime_before_update_entity(session, entity):
     """update an entity -> set modification date"""

--- a/server/schemahooks.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/server/schemahooks.py	Thu Jul 23 15:28:41 2009 +0200
@@ -26,7 +26,7 @@
 # core entity and relation types which can't be removed
 CORE_ETYPES = list(BASE_TYPES) + ['CWEType', 'CWRType', 'CWUser', 'CWGroup',
                                   'CWConstraint', 'CWAttribute', 'CWRelation']
-CORE_RTYPES = ['eid', 'creation_date', 'modification_date',
+CORE_RTYPES = ['eid', 'creation_date', 'modification_date', 'cwuri',
                'login', 'upassword', 'name',
                'is', 'instanceof', 'owned_by', 'created_by', 'in_group',
                'relation_type', 'from_entity', 'to_entity',
@@ -283,7 +283,7 @@
                            prefix=SQL_PREFIX)
     relrqls = []
     for rtype in ('is', 'is_instance_of', 'creation_date', 'modification_date',
-                  'created_by', 'owned_by'):
+                  'cwuri', 'created_by', 'owned_by'):
         rschema = schema[rtype]
         sampletype = rschema.subjects()[0]
         desttype = rschema.objects()[0]

--- a/server/test/unittest_hooks.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/server/test/unittest_hooks.py	Thu Jul 23 15:28:41 2009 +0200
@@ -618,6 +618,11 @@
         self.failUnless(cu.execute("INSERT Note X: X type 'a', X in_state S WHERE S name 'todo'"))
         cnx.commit()
 
+    def test_metadata_cwuri(self):
+        eid = self.execute('INSERT Note X')[0][0]
+        cwuri = self.execute('Any U WHERE X eid %s, X cwuri U' % eid)[0][0]
+        self.assertEquals(cwuri, self.repo.config['base-url'] + 'eid/%s' % eid)
+
     def test_metadata_creation_modification_date(self):
         _now = datetime.now()
         eid = self.execute('INSERT Note X')[0][0]

--- a/test/unittest_schema.py	Thu Jul 23 15:17:11 2009 +0200
+++ b/test/unittest_schema.py	Thu Jul 23 15:28:41 2009 +0200
@@ -150,7 +150,7 @@
                              'CWCache', 'CWConstraint', 'CWConstraintType', 'CWEType',
                              'CWAttribute', 'CWGroup', 'EmailAddress', 'CWRelation',
                              'CWPermission', 'CWProperty', 'CWRType', 'CWUser',
-                             'File', 'Float', 'Image', 'Int', 'Interval', 'Note',
+                             'ExternalUri', 'File', 'Float', 'Image', 'Int', 'Interval', 'Note',
                              'Password', 'Personne',
                              'RQLExpression',
                              'Societe', 'State', 'String', 'SubNote', 'Tag', 'Time',
@@ -163,7 +163,7 @@
 
                               'cardinality', 'comment', 'comment_format',
                               'composite', 'condition', 'connait', 'constrained_by', 'content',
-                              'content_format', 'created_by', 'creation_date', 'cstrtype',
+                              'content_format', 'created_by', 'creation_date', 'cstrtype', 'cwuri',
 
                               'data', 'data_encoding', 'data_format', 'defaultval', 'delete_permission',
                               'description', 'description_format', 'destination_state',
@@ -179,7 +179,7 @@
 
                               'label', 'last_login_time', 'login',
 
-                              'mainvars', 'meta', 'modification_date',
+                              'mainvars', 'modification_date',
 
                               'name', 'nom',
 
@@ -193,7 +193,7 @@
 
                               'tags', 'timestamp', 'title', 'to_entity', 'to_state', 'transition_of', 'travaille', 'type',
 
-                              'upassword', 'update_permission', 'use_email',
+                              'upassword', 'update_permission', 'uri', 'use_email',
 
                               'value',
 
@@ -203,7 +203,7 @@
 
         eschema = schema.eschema('CWUser')
         rels = sorted(str(r) for r in eschema.subject_relations())
-        self.assertListEquals(rels, ['created_by', 'creation_date', 'eid',
+        self.assertListEquals(rels, ['created_by', 'creation_date', 'cwuri', 'eid',
                                      'evaluee', 'firstname', 'has_text', 'identity',
                                      'in_group', 'in_state', 'is',
                                      'is_instance_of', 'last_login_time',