--- a/cwvreg.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/cwvreg.py	Thu Jan 23 13:47:28 2014 +0100
@@ -701,7 +701,7 @@
 
     def solutions(self, req, rqlst, args):
         def type_from_eid(eid, req=req):
-            return req.describe(eid)[0]
+            return req.entity_metas(eid)['type']
         return self.rqlhelper.compute_solutions(rqlst, {'eid': type_from_eid}, args)
 
     def parse(self, req, rql, args=None):

--- a/dbapi.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/dbapi.py	Thu Jan 23 13:47:28 2014 +0100
@@ -91,8 +91,6 @@
         self.close_on_del = close
 
 
-
-
 @deprecated('[3.19] the dbapi is deprecated. Have a look at the new repoapi.')
 def _repo_connect(repo, login, **kwargs):
     """Constructor to create a new connection to the given CubicWeb repository.
@@ -360,14 +358,19 @@
 
     # server session compat layer #############################################
 
-    def describe(self, eid, asdict=False):
+    def entity_metas(self, eid):
         """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
-        return self.cnx.describe(eid, asdict)
+        return self.cnx.entity_metas(eid)
 
     def source_defs(self):
         """return the definition of sources used by the repository."""
         return self.cnx.source_defs()
 
+    @deprecated('[3.19] use .entity_metas(eid) instead')
+    def describe(self, eid, asdict=False):
+        """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
+        return self.cnx.describe(eid, asdict)
+
     # these are overridden by set_log_methods below
     # only defining here to prevent pylint from complaining
     info = warning = error = critical = exception = debug = lambda msg,*a,**kw: None
@@ -671,16 +674,31 @@
                  stacklevel=2)
         return self._repo.get_option_value(option)
 
+
+    @check_not_closed
+    def entity_metas(self, eid):
+        """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
+        return self._repo.entity_metas(self.sessionid, eid, **self._txid())
+
+    @deprecated('[3.19] use .entity_metas(eid) instead')
     @check_not_closed
     def describe(self, eid, asdict=False):
-        metas = self._repo.describe(self.sessionid, eid, **self._txid())
-        if len(metas) == 3: # backward compat
-            metas = list(metas)
-            metas.append(metas[1])
+        try:
+            metas = self._repo.entity_metas(self.sessionid, eid, **self._txid())
+        except AttributeError:
+            metas = self._repo.describe(self.sessionid, eid, **self._txid())
+            # talking to pre 3.19 repository
+            if len(metas) == 3: # even older backward compat
+                metas = list(metas)
+                metas.append(metas[1])
+            if asdict:
+                return dict(zip(('type', 'source', 'extid', 'asource'), metas))
+            return metas[:-1]
         if asdict:
-            return dict(zip(('type', 'source', 'extid', 'asource'), metas))
-        # XXX :-1 for cw compat, use asdict=True for full information
-        return metas[:-1]
+            metas['asource'] = meta['source'] # XXX pre 3.19 client compat
+            return metas
+        return metas['type'], metas['source'], metas['extid']
+
 
     # db-api like interface ####################################################
 

--- a/devtools/fake.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/devtools/fake.py	Thu Jan 23 13:47:28 2014 +0100
@@ -191,9 +191,6 @@
             source.after_entity_insertion(session, extid, entity)
             return eid
 
-    def eid2extid(self, source, eid, session=None):
-        return self.eids[eid]
-
 
 class FakeSource(object):
     dbhelper = get_db_helper('sqlite')

--- a/entity.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/entity.py	Thu Jan 23 13:47:28 2014 +0100
@@ -633,11 +633,9 @@
 
     @cached
     def cw_metainformation(self):
-        res = self._cw.describe(self.eid, asdict=True)
-        # use 'asource' and not 'source' since this is the actual source,
-        # while 'source' is the physical source (where it's stored)
-        res['source'] = self._cw.source_defs()[res.pop('asource')]
-        return res
+        metas = self._cw.entity_metas(self.eid)
+        metas['source'] = self._cw.source_defs()[metas['source']]
+        return metas
 
     def cw_check_perm(self, action):
         self.e_schema.check_perm(self._cw, action, eid=self.eid)

--- a/hooks/integrity.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/integrity.py	Thu Jan 23 13:47:28 2014 +0100
@@ -85,7 +85,7 @@
             if rtype in pendingrtypes:
                 continue
             if not session.execute(self.base_rql % rtype, {'x': eid}):
-                etype = session.describe(eid)[0]
+                etype = session.entity_metas(eid)['type']
                 msg = _('at least one relation %(rtype)s is required on '
                         '%(etype)s (%(eid)s)')
                 raise validation_error(eid, {(rtype, self.role): msg},
@@ -325,7 +325,7 @@
         for eid, rtype in self.get_data():
             # don't do anything if the entity is being deleted
             if eid not in pendingeids:
-                etype = session.describe(eid)[0]
+                etype = session.entity_metas(eid)['type']
                 key = (etype, rtype)
                 if key not in eids_by_etype_rtype:
                     eids_by_etype_rtype[key] = [str(eid)]

--- a/hooks/metadata.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/metadata.py	Thu Jan 23 13:47:28 2014 +0100
@@ -1,4 +1,4 @@
-# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# copyright 2003-2013 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
 # contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
 #
 # This file is part of CubicWeb.
@@ -158,8 +158,8 @@
         entity = self.entity
         extid = entity.cw_metainformation()['extid']
         repo._type_source_cache[entity.eid] = (
-            entity.cw_etype, self.newsource.uri, None, self.newsource.uri)
-        repo._extid_cache[(extid, 'system')] = -entity.eid
+            entity.cw_etype, None, self.newsource.uri)
+        repo._extid_cache[extid] = -entity.eid
 
 
 class ChangeEntitySourceDeleteHook(MetaDataHook):
@@ -204,7 +204,7 @@
             self._cw.system_sql('UPDATE entities SET eid=-eid WHERE eid=%(eid)s',
                                 {'eid': self.eidfrom})
             attrs = {'type': entity.cw_etype, 'eid': entity.eid, 'extid': None,
-                     'source': 'system', 'asource': 'system'}
+                     'asource': 'system'}
             self._cw.system_sql(syssource.sqlgen.insert('entities', attrs), attrs)
             # register an operation to update repository/sources caches
             ChangeEntitySourceUpdateCaches(self._cw, entity=entity,

--- a/hooks/security.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/security.py	Thu Jan 23 13:47:28 2014 +0100
@@ -78,8 +78,8 @@
     def precommit_event(self):
         session = self.session
         for action, rschema, eidfrom, eidto in self.get_data():
-            rdef = rschema.rdef(session.describe(eidfrom)[0],
-                                session.describe(eidto)[0])
+            rdef = rschema.rdef(session.entity_metas(eidfrom)['type'],
+                                session.entity_metas(eidto)['type'])
             rdef.check_perm(session, action, fromeid=eidfrom, toeid=eidto)
 
 
@@ -134,8 +134,8 @@
             if (self.eidfrom, self.rtype, self.eidto) in nocheck:
                 return
             rschema = self._cw.repo.schema[self.rtype]
-            rdef = rschema.rdef(self._cw.describe(self.eidfrom)[0],
-                                self._cw.describe(self.eidto)[0])
+            rdef = rschema.rdef(self._cw.entity_metas(self.eidfrom)['type'],
+                                self._cw.entity_metas(self.eidto)['type'])
             rdef.check_perm(self._cw, 'add', fromeid=self.eidfrom, toeid=self.eidto)
 
 
@@ -153,8 +153,8 @@
                 CheckRelationPermissionOp.get_instance(self._cw).add_data(
                     ('add', rschema, self.eidfrom, self.eidto) )
             else:
-                rdef = rschema.rdef(self._cw.describe(self.eidfrom)[0],
-                                    self._cw.describe(self.eidto)[0])
+                rdef = rschema.rdef(self._cw.entity_metas(self.eidfrom)['type'],
+                                    self._cw.entity_metas(self.eidto)['type'])
                 rdef.check_perm(self._cw, 'add', fromeid=self.eidfrom, toeid=self.eidto)
 
 
@@ -167,7 +167,7 @@
         if (self.eidfrom, self.rtype, self.eidto) in nocheck:
             return
         rschema = self._cw.repo.schema[self.rtype]
-        rdef = rschema.rdef(self._cw.describe(self.eidfrom)[0],
-                            self._cw.describe(self.eidto)[0])
+        rdef = rschema.rdef(self._cw.entity_metas(self.eidfrom)['type'],
+                            self._cw.entity_metas(self.eidto)['type'])
         rdef.check_perm(self._cw, 'delete', fromeid=self.eidfrom, toeid=self.eidto)
 

--- a/hooks/syncschema.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/syncschema.py	Thu Jan 23 13:47:28 2014 +0100
@@ -294,9 +294,9 @@
         self.info('renamed table %s to %s', oldname, newname)
         sqlexec('UPDATE entities SET type=%(newname)s WHERE type=%(oldname)s',
                 {'newname': newname, 'oldname': oldname})
-        for eid, (etype, uri, extid, auri) in self.session.repo._type_source_cache.items():
+        for eid, (etype, extid, auri) in self.session.repo._type_source_cache.items():
             if etype == oldname:
-                self.session.repo._type_source_cache[eid] = (newname, uri, extid, auri)
+                self.session.repo._type_source_cache[eid] = (newname, extid, auri)
         # XXX transaction records
 
     def precommit_event(self):
@@ -1180,7 +1180,7 @@
 
     def __call__(self):
         action = self.rtype.split('_', 1)[0]
-        if self._cw.describe(self.eidto)[0] == 'CWGroup':
+        if self._cw.entity_metas(self.eidto)['type'] == 'CWGroup':
             MemSchemaPermissionAdd(self._cw, action=action, eid=self.eidfrom,
                                    group_eid=self.eidto)
         else: # RQLExpression
@@ -1201,7 +1201,7 @@
         if self._cw.deleted_in_transaction(self.eidfrom):
             return
         action = self.rtype.split('_', 1)[0]
-        if self._cw.describe(self.eidto)[0] == 'CWGroup':
+        if self._cw.entity_metas(self.eidto)['type'] == 'CWGroup':
             MemSchemaPermissionDel(self._cw, action=action, eid=self.eidfrom,
                                    group_eid=self.eidto)
         else: # RQLExpression

--- a/hooks/syncsession.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/syncsession.py	Thu Jan 23 13:47:28 2014 +0100
@@ -229,7 +229,7 @@
     def __call__(self):
         session = self._cw
         eidfrom = self.eidfrom
-        if not session.describe(eidfrom)[0] == 'CWProperty':
+        if not session.entity_metas(eidfrom)['type'] == 'CWProperty':
             return
         key, value = session.execute('Any K,V WHERE P eid %(x)s,P pkey K,P value V',
                                      {'x': eidfrom})[0]

--- a/hooks/workflow.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/hooks/workflow.py	Thu Jan 23 13:47:28 2014 +0100
@@ -32,12 +32,8 @@
     nocheck = session.transaction_data.setdefault('skip-security', set())
     nocheck.add((x, 'in_state', oldstate))
     nocheck.add((x, 'in_state', newstate))
-    # delete previous state first unless in_state isn't stored in the system
-    # source
-    fromsource = session.describe(x)[1]
-    if fromsource == 'system' or \
-           not session.repo.sources_by_uri[fromsource].support_relation('in_state'):
-        session.delete_relation(x, 'in_state', oldstate)
+    # delete previous state first
+    session.delete_relation(x, 'in_state', oldstate)
     session.add_relation(x, 'in_state', newstate)
 
 

--- a/misc/migration/3.19.0_Any.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/misc/migration/3.19.0_Any.py	Thu Jan 23 13:47:28 2014 +0100
@@ -1,2 +1,4 @@
 sql('DROP TABLE "deleted_entities"')
 sql('ALTER TABLE "entities" DROP COLUMN "mtime"')
+sql('ALTER TABLE "entities" DROP COLUMN "source"')
+

--- a/repoapi.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/repoapi.py	Thu Jan 23 13:47:28 2014 +0100
@@ -241,7 +241,8 @@
         """Return the value for `option` in the configuration."""
         return self._session.repo.get_option_value(option)
 
-    describe = _srv_cnx_func('describe')
+    entity_metas = _srv_cnx_func('entity_metas')
+    describe = _srv_cnx_func('describe') # XXX deprecated in 3.19
 
     # undo support ############################################################
 

--- a/req.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/req.py	Thu Jan 23 13:47:28 2014 +0100
@@ -131,7 +131,7 @@
         """
         eid = int(eid)
         if etype is None:
-            etype = self.describe(eid)[0]
+            etype = self.entity_metas(eid)['type']
         rset = ResultSet([(eid,)], 'Any X WHERE X eid %(x)s', {'x': eid},
                          [(etype,)])
         rset.req = self

--- a/schema.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/schema.py	Thu Jan 23 13:47:28 2014 +0100
@@ -812,20 +812,20 @@
             assert not ('fromeid' in kwargs or 'toeid' in kwargs), kwargs
             assert action in ('read', 'update')
             if 'eid' in kwargs:
-                subjtype = _cw.describe(kwargs['eid'])[0]
+                subjtype = _cw.entity_metas(kwargs['eid'])['type']
             else:
                 subjtype = objtype = None
         else:
             assert not 'eid' in kwargs, kwargs
             assert action in ('read', 'add', 'delete')
             if 'fromeid' in kwargs:
-                subjtype = _cw.describe(kwargs['fromeid'])[0]
+                subjtype = _cw.entity_metas(kwargs['fromeid'])['type']
             elif 'frometype' in kwargs:
                 subjtype = kwargs.pop('frometype')
             else:
                 subjtype = None
             if 'toeid' in kwargs:
-                objtype = _cw.describe(kwargs['toeid'])[0]
+                objtype = _cw.entity_metas(kwargs['toeid'])['type']
             elif 'toetype' in kwargs:
                 objtype = kwargs.pop('toetype')
             else:

--- a/server/checkintegrity.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/checkintegrity.py	Thu Jan 23 13:47:28 2014 +0100
@@ -39,24 +39,12 @@
     """return true if the eid is a valid eid"""
     if eid in eids:
         return eids[eid]
-    sqlcursor.execute('SELECT type, source FROM entities WHERE eid=%s' % eid)
+    sqlcursor.execute('SELECT type FROM entities WHERE eid=%s' % eid)
     try:
-        etype, source = sqlcursor.fetchone()
+        etype = sqlcursor.fetchone()[0]
     except Exception:
         eids[eid] = False
         return False
-    if source and source != 'system':
-        try:
-            # insert eid *and* etype to attempt checking entity has not been
-            # replaced by another subsquently to a restore of an old dump
-            if session.execute('Any X WHERE X is %s, X eid %%(x)s' % etype,
-                               {'x': eid}):
-                eids[eid] = True
-                return True
-        except Exception: # TypeResolverError, Unauthorized...
-            pass
-        eids[eid] = False
-        return False
     if etype not in session.vreg.schema:
         eids[eid] = False
         return False

--- a/server/hook.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/hook.py	Thu Jan 23 13:47:28 2014 +0100
@@ -460,10 +460,10 @@
         if kwargs.get('rtype') not in self.expected:
             return 0
         if self.frometypes is not None and \
-               req.describe(kwargs['eidfrom'])[0] not in self.frometypes:
+               req.entity_metas(kwargs['eidfrom'])['type'] not in self.frometypes:
             return 0
         if self.toetypes is not None and \
-               req.describe(kwargs['eidto'])[0] not in self.toetypes:
+               req.entity_metas(kwargs['eidto'])['type'] not in self.toetypes:
             return 0
         return 1
 
@@ -604,7 +604,7 @@
     def __call__(self):
         assert self.main_rtype
         for eid in (self.eidfrom, self.eidto):
-            etype = self._cw.describe(eid)[0]
+            etype = self._cw.entity_metas(eid)['type']
             if self.main_rtype not in self._cw.vreg.schema.eschema(etype).subjrels:
                 return
         if self.rtype in self.subject_relations:
@@ -640,7 +640,7 @@
     skip_object_relations = ()
 
     def __call__(self):
-        eschema = self._cw.vreg.schema.eschema(self._cw.describe(self.eidfrom)[0])
+        eschema = self._cw.vreg.schema.eschema(self._cw.entity_metas(self.eidfrom)['type'])
         execute = self._cw.execute
         for rel in self.subject_relations:
             if rel in eschema.subjrels and not rel in self.skip_subject_relations:
@@ -664,7 +664,7 @@
     events = ('after_delete_relation',)
 
     def __call__(self):
-        eschema = self._cw.vreg.schema.eschema(self._cw.describe(self.eidfrom)[0])
+        eschema = self._cw.vreg.schema.eschema(self._cw.entity_metas(self.eidfrom)['type'])
         execute = self._cw.execute
         for rel in self.subject_relations:
             if rel in eschema.subjrels and not rel in self.skip_subject_relations:

--- a/server/querier.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/querier.py	Thu Jan 23 13:47:28 2014 +0100
@@ -71,7 +71,7 @@
     try:
         return solution[term.name]
     except AttributeError:
-        return session.describe(term.eval(args))[0]
+        return session.entity_metas(term.eval(args))['type']
 
 def check_read_access(session, rqlst, solution, args):
     """Check that the given user has credentials to access data read by the
@@ -667,7 +667,7 @@
 
 def _build_descr(tx, result, basedescription, todetermine):
     description = []
-    etype_from_eid = tx.describe
+    entity_metas = tx.entity_metas
     todel = []
     for i, row in enumerate(result):
         row_descr = basedescription[:]
@@ -681,7 +681,7 @@
                 row_descr[index] = etype_from_pyobj(value)
             else:
                 try:
-                    row_descr[index] = etype_from_eid(value)[0]
+                    row_descr[index] = entity_metas(value)['type']
                 except UnknownEid:
                     tx.error('wrong eid %s in repository, you should '
                              'db-check the database' % value)

--- a/server/repository.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/repository.py	Thu Jan 23 13:47:28 2014 +0100
@@ -188,9 +188,9 @@
         self.sources_by_uri = {'system': self.system_source}
         # querier helper, need to be created after sources initialization
         self.querier = querier.QuerierHelper(self, self.schema)
-        # cache eid -> (type, physical source, extid, actual source)
+        # cache eid -> (type, extid, actual source)
         self._type_source_cache = {}
-        # cache (extid, source uri) -> eid
+        # cache extid -> eid
         self._extid_cache = {}
         # open some connection sets
         if config.init_cnxset_pool:
@@ -728,13 +728,35 @@
         finally:
             session.free_cnxset()
 
+    @deprecated('[3.19] use .entity_metas(sessionid, eid, txid) instead')
     def describe(self, sessionid, eid, txid=None):
         """return a tuple `(type, physical source uri, extid, actual source
         uri)` for the entity of the given `eid`
+
+        As of 3.19, physical source uri is always the system source.
         """
         session = self._get_session(sessionid, setcnxset=True, txid=txid)
         try:
-            return self.type_and_source_from_eid(eid, session)
+            etype, extid, source = self.type_and_source_from_eid(eid, session)
+            return etype, source, extid, source
+        finally:
+            session.free_cnxset()
+
+    def entity_metas(self, sessionid, eid, txid=None):
+        """return a dictionary containing meta-datas for the entity of the given
+        `eid`. Available keys are:
+
+        * 'type', the entity's type name,
+
+        * 'source', the name of the source from which this entity's coming from,
+
+        * 'extid', the identifierfor this entity in its originating source, as
+          an encoded string or `None` for entities from the 'system' source.
+        """
+        session = self._get_session(sessionid, setcnxset=True, txid=txid)
+        try:
+            etype, extid, source = self.type_and_source_from_eid(eid, session)
+            return {'type': etype, 'source': source, 'extid': extid}
         finally:
             session.free_cnxset()
 
@@ -934,8 +956,8 @@
     # * correspondance between eid and local id (i.e. specific to a given source)
 
     def type_and_source_from_eid(self, eid, session=None):
-        """return a tuple `(type, physical source uri, extid, actual source
-        uri)` for the entity of the given `eid`
+        """return a tuple `(type, extid, actual source uri)` for the entity of
+        the given `eid`
         """
         try:
             eid = int(eid)
@@ -950,15 +972,13 @@
             else:
                 free_cnxset = False
             try:
-                etype, uri, extid, auri = self.system_source.eid_type_source(
+                etype, extid, auri = self.system_source.eid_type_source(
                     session, eid)
             finally:
                 if free_cnxset:
                     session.free_cnxset()
-            self._type_source_cache[eid] = (etype, uri, extid, auri)
-            if uri != 'system':
-                self._extid_cache[(extid, uri)] = eid
-            return etype, uri, extid, auri
+            self._type_source_cache[eid] = (etype, extid, auri)
+            return etype, extid, auri
 
     def clear_caches(self, eids):
         etcache = self._type_source_cache
@@ -966,9 +986,9 @@
         rqlcache = self.querier._rql_cache
         for eid in eids:
             try:
-                etype, uri, extid, auri = etcache.pop(int(eid)) # may be a string in some cases
+                etype, extid, auri = etcache.pop(int(eid)) # may be a string in some cases
                 rqlcache.pop( ('%s X WHERE X eid %s' % (etype, eid),), None)
-                extidcache.pop((extid, uri), None)
+                extidcache.pop(extid, None)
             except KeyError:
                 etype = None
             rqlcache.pop( ('Any X WHERE X eid %s' % eid,), None)
@@ -978,10 +998,6 @@
         """return the type of the entity with id <eid>"""
         return self.type_and_source_from_eid(eid, session)[0]
 
-    def source_from_eid(self, eid, session=None):
-        """return the source for the given entity's eid"""
-        return self.sources_by_uri[self.type_and_source_from_eid(eid, session)[1]]
-
     def querier_cache_key(self, session, rql, args, eidkeys):
         cachekey = [rql]
         for key in sorted(eidkeys):
@@ -997,14 +1013,6 @@
             args[key] = int(args[key])
         return tuple(cachekey)
 
-    def eid2extid(self, source, eid, session=None):
-        """get local id from an eid"""
-        etype, uri, extid, _ = self.type_and_source_from_eid(eid, session)
-        if source.uri != uri:
-            # eid not from the given source
-            raise UnknownEid(eid)
-        return extid
-
     def extid2eid(self, source, extid, etype, session=None, insert=True,
                   complete=True, commit=True, sourceparams=None):
         """Return eid from a local id. If the eid is a negative integer, that
@@ -1029,20 +1037,18 @@
         6. unless source's :attr:`should_call_hooks` tell otherwise,
           'before_add_entity' hooks are called
         """
-        uri = 'system'
-        cachekey = (extid, uri)
         try:
-            return self._extid_cache[cachekey]
+            return self._extid_cache[extid]
         except KeyError:
             pass
         free_cnxset = False
         if session is None:
             session = self.internal_session()
             free_cnxset = True
-        eid = self.system_source.extid2eid(session, uri, extid)
+        eid = self.system_source.extid2eid(session, extid)
         if eid is not None:
-            self._extid_cache[cachekey] = eid
-            self._type_source_cache[eid] = (etype, uri, extid, source.uri)
+            self._extid_cache[extid] = eid
+            self._type_source_cache[eid] = (etype, extid, source.uri)
             if free_cnxset:
                 session.free_cnxset()
             return eid
@@ -1059,8 +1065,8 @@
             free_cnxset = True
         try:
             eid = self.system_source.create_eid(session)
-            self._extid_cache[cachekey] = eid
-            self._type_source_cache[eid] = (etype, uri, extid, source.uri)
+            self._extid_cache[extid] = eid
+            self._type_source_cache[eid] = (etype, extid, source.uri)
             entity = source.before_entity_insertion(
                 session, extid, etype, eid, sourceparams)
             if source.should_call_hooks:
@@ -1081,7 +1087,7 @@
             else:
                 # XXX do some cleanup manually so that the transaction has a
                 # chance to be commited, with simply this entity discarded
-                self._extid_cache.pop(cachekey, None)
+                self._extid_cache.pop(extid, None)
                 self._type_source_cache.pop(eid, None)
                 if 'entity' in locals():
                     hook.CleanupDeletedEidsCacheOp.get_instance(session).add_data(entity.eid)
@@ -1177,15 +1183,12 @@
         Return entity's ext id if the source isn't the system source.
         """
         session.set_entity_cache(entity)
-        suri = source.uri
-        if suri == 'system':
+        if source.uri == 'system':
             extid = None
         else:
-            suri = 'system'
             extid = source.get_extid(entity)
-            self._extid_cache[(str(extid), suri)] = entity.eid
-        self._type_source_cache[entity.eid] = (entity.cw_etype, suri, extid,
-                                               source.uri)
+            self._extid_cache[str(extid)] = entity.eid
+        self._type_source_cache[entity.eid] = (entity.cw_etype, extid, source.uri)
         return extid
 
     def glob_add_entity(self, session, edited):

--- a/server/session.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/session.py	Thu Jan 23 13:47:28 2014 +0100
@@ -452,6 +452,7 @@
         if cnxid is None:
             cnxid = '%s-%s' % (session.id, uuid4().hex)
         self.connectionid = cnxid
+        self.sessionid = session.id
         #: self._session_handled
         #: are the life cycle of this Connection automatically controlled by the
         #: Session This is the old backward compatibility mode
@@ -788,7 +789,7 @@
             rset.rows.append([targeteid])
             if not isinstance(rset.description, list): # else description not set
                 rset.description = list(rset.description)
-            rset.description.append([self.describe(targeteid)[0]])
+            rset.description.append([self.entity_metas(targeteid)['type']])
             targetentity = self.entity_from_eid(targeteid)
             if targetentity.cw_rset is None:
                 targetentity.cw_rset = rset
@@ -981,21 +982,24 @@
     def source_defs(self):
         return self.repo.source_defs()
 
+    @deprecated('[3.19] use .entity_metas(eid) instead')
     @_with_cnx_set
     @_open_only
     def describe(self, eid, asdict=False):
         """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
-        metas = self.repo.type_and_source_from_eid(eid, self)
+        etype, extid, source = self.repo.type_and_source_from_eid(eid, self)
+        metas = {'type': etype, 'source': source, 'extid': extid}
         if asdict:
-            return dict(zip(('type', 'source', 'extid', 'asource'), metas))
-        # XXX :-1 for cw compat, use asdict=True for full information
-        return metas[:-1]
+            metas['asource'] = meta['source'] # XXX pre 3.19 client compat
+            return meta
+        return etype, source, extid
 
     @_with_cnx_set
     @_open_only
-    def source_from_eid(self, eid):
-        """return the source where the entity with id <eid> is located"""
-        return self.repo.source_from_eid(eid, self)
+    def entity_metas(self, eid):
+        """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
+        etype, extid, source = self.repo.type_and_source_from_eid(eid, self)
+        return {'type': etype, 'source': source, 'extid': extid}
 
     # core method #############################################################
 
@@ -1589,8 +1593,8 @@
     drop_entity_cache = cnx_meth('drop_entity_cache')
 
     source_defs = cnx_meth('source_defs')
-    describe = cnx_meth('describe')
-    source_from_eid = cnx_meth('source_from_eid')
+    entity_metas = cnx_meth('entity_metas')
+    describe = cnx_meth('describe') # XXX deprecated in 3.19
 
 
     @deprecated('[3.19] use a Connection object instead')

--- a/server/sources/__init__.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/sources/__init__.py	Thu Jan 23 13:47:28 2014 +0100
@@ -450,10 +450,6 @@
         raise NotImplementedError(self)
 
 
-    @deprecated('[3.13] use repo.eid2extid(source, eid, session)')
-    def eid2extid(self, eid, session=None):
-        return self.repo.eid2extid(self, eid, session)
-
     @deprecated('[3.13] use extid2eid(source, value, etype, session, **kwargs)')
     def extid2eid(self, value, etype, session=None, **kwargs):
         return self.repo.extid2eid(self, value, etype, session, **kwargs)

--- a/server/sources/native.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/sources/native.py	Thu Jan 23 13:47:28 2014 +0100
@@ -592,7 +592,7 @@
         else: # used by data import
             etypes = {}
             for subject, object in subj_obj_list:
-                etype = session.describe(subject)[0]
+                etype = session.entity_metas(subject)['type']
                 if etype in etypes:
                     etypes[etype].append((subject, object))
                 else:
@@ -617,7 +617,7 @@
     def _delete_relation(self, session, subject, rtype, object, inlined=False):
         """delete a relation from the source"""
         if inlined:
-            table = SQL_PREFIX + session.describe(subject)[0]
+            table = SQL_PREFIX + session.entity_metas(subject)['type']
             column = SQL_PREFIX + rtype
             sql = 'UPDATE %s SET %s=NULL WHERE %seid=%%(eid)s' % (table, column,
                                                                   SQL_PREFIX)
@@ -764,7 +764,7 @@
 
     def eid_type_source(self, session, eid): # pylint: disable=E0202
         """return a tuple (type, source, extid) for the entity with id <eid>"""
-        sql = 'SELECT type, source, extid, asource FROM entities WHERE eid=%s' % eid
+        sql = 'SELECT type, extid, asource FROM entities WHERE eid=%s' % eid
         res = self._eid_type_source(session, eid, sql)
         if res[-2] is not None:
             if not isinstance(res, list):
@@ -774,7 +774,7 @@
 
     def eid_type_source_pre_131(self, session, eid):
         """return a tuple (type, source, extid) for the entity with id <eid>"""
-        sql = 'SELECT type, source, extid FROM entities WHERE eid=%s' % eid
+        sql = 'SELECT type, extid FROM entities WHERE eid=%s' % eid
         res = self._eid_type_source(session, eid, sql)
         if not isinstance(res, list):
             res = list(res)
@@ -783,13 +783,12 @@
         res.append(res[1])
         return res
 
-    def extid2eid(self, session, source_uri, extid):
+    def extid2eid(self, session, extid):
         """get eid from an external id. Return None if no record found."""
         assert isinstance(extid, str)
         cursor = self.doexec(session,
-                             'SELECT eid FROM entities '
-                             'WHERE extid=%(x)s AND source=%(s)s',
-                             {'x': b64encode(extid), 's': source_uri})
+                             'SELECT eid FROM entities WHERE extid=%(x)s',
+                             {'x': b64encode(extid)})
         # XXX testing rowcount cause strange bug with sqlite, results are there
         #     but rowcount is 0
         #if cursor.rowcount > 0:
@@ -863,7 +862,7 @@
                 assert isinstance(extid, str)
                 extid = b64encode(extid)
             attrs = {'type': entity.cw_etype, 'eid': entity.eid, 'extid': extid,
-                     'source': 'system', 'asource': source.uri}
+                     'asource': source.uri}
             self._handle_insert_entity_sql(session, self.sqlgen.insert('entities', attrs), attrs)
             # insert core relations: is, is_instance_of and cw_source
             try:
@@ -1349,7 +1348,6 @@
 CREATE TABLE entities (
   eid INTEGER PRIMARY KEY NOT NULL,
   type VARCHAR(64) NOT NULL,
-  source VARCHAR(128) NOT NULL,
   asource VARCHAR(128) NOT NULL,
   extid VARCHAR(256)
 );;

--- a/server/ssplanner.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/ssplanner.py	Thu Jan 23 13:47:28 2014 +0100
@@ -90,7 +90,7 @@
                 # to be selected)
                 if checkread and eid not in neweids:
                     with session.security_enabled(read=False):
-                        eschema(session.describe(eid)[0]).check_perm(
+                        eschema(session.entity_metas(eid)['type']).check_perm(
                             session, 'read', eid=eid)
                 eidconsts[lhs.variable] = eid
     return eidconsts

--- a/server/test/unittest_datafeed.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/test/unittest_datafeed.py	Thu Jan 23 13:47:28 2014 +0100
@@ -1,4 +1,4 @@
-# copyright 2011-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# copyright 2011-2013 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
 # contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
 #
 # This file is part of CubicWeb.
@@ -70,8 +70,8 @@
             self.assertEqual(entity.absolute_url(), 'http://www.cubicweb.org/')
             # test repo cache keys
             self.assertEqual(self.repo._type_source_cache[entity.eid],
-                             ('Card', 'system', 'http://www.cubicweb.org/', 'myfeed'))
-            self.assertEqual(self.repo._extid_cache[('http://www.cubicweb.org/', 'system')],
+                             ('Card', 'http://www.cubicweb.org/', 'myfeed'))
+            self.assertEqual(self.repo._extid_cache['http://www.cubicweb.org/'],
                              entity.eid)
             # test repull
             session.set_cnxset()
@@ -86,8 +86,8 @@
             self.assertEqual(stats['created'], set())
             self.assertEqual(stats['updated'], set((entity.eid,)))
             self.assertEqual(self.repo._type_source_cache[entity.eid],
-                             ('Card', 'system', 'http://www.cubicweb.org/', 'myfeed'))
-            self.assertEqual(self.repo._extid_cache[('http://www.cubicweb.org/', 'system')],
+                             ('Card', 'http://www.cubicweb.org/', 'myfeed'))
+            self.assertEqual(self.repo._extid_cache['http://www.cubicweb.org/'],
                              entity.eid)
 
         self.assertEqual(dfsource.source_cwuris(self.session),
@@ -109,8 +109,8 @@
                           'extid': 'http://www.cubicweb.org/'}
                          )
         self.assertEqual(self.repo._type_source_cache[entity.eid],
-                         ('Card', 'system', 'http://www.cubicweb.org/', 'myrenamedfeed'))
-        self.assertEqual(self.repo._extid_cache[('http://www.cubicweb.org/', 'system')],
+                         ('Card', 'http://www.cubicweb.org/', 'myrenamedfeed'))
+        self.assertEqual(self.repo._extid_cache['http://www.cubicweb.org/'],
                          entity.eid)
 
         # test_delete_source

--- a/server/test/unittest_repository.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/server/test/unittest_repository.py	Thu Jan 23 13:47:28 2014 +0100
@@ -424,12 +424,8 @@
         cnxid = repo.connect(self.admlogin, password=self.admpassword)
         session = repo._get_session(cnxid, setcnxset=True)
         self.assertEqual(repo.type_and_source_from_eid(2, session),
-                         ('CWGroup', 'system', None, 'system'))
+                         ('CWGroup', None, 'system'))
         self.assertEqual(repo.type_from_eid(2, session), 'CWGroup')
-        self.assertEqual(repo.source_from_eid(2, session).uri, 'system')
-        self.assertEqual(repo.eid2extid(repo.system_source, 2, session), None)
-        class dummysource: uri = 'toto'
-        self.assertRaises(UnknownEid, repo.eid2extid, dummysource, 2, session)
         repo.close(cnxid)
 
     def test_public_api(self):
@@ -445,7 +441,9 @@
         repo = self.repo
         cnxid = repo.connect(self.admlogin, password=self.admpassword)
         self.assertEqual(repo.user_info(cnxid), (6, 'admin', set([u'managers']), {}))
-        self.assertEqual(repo.describe(cnxid, 2), (u'CWGroup', u'system', None, 'system'))
+        self.assertEqual({'type': u'CWGroup', 'extid': None, 'source': 'system'},
+                         repo.entity_metas(cnxid, 2))
+        self.assertEqual(repo.describe(cnxid, 2), (u'CWGroup', 'system', None, 'system'))
         repo.close(cnxid)
         self.assertRaises(BadConnectionId, repo.user_info, cnxid)
         self.assertRaises(BadConnectionId, repo.describe, cnxid, 1)
@@ -670,15 +668,6 @@
         self.session.set_cnxset()
         self.assert_(self.repo.system_source.create_eid(self.session))
 
-    def test_source_from_eid(self):
-        self.session.set_cnxset()
-        self.assertEqual(self.repo.source_from_eid(1, self.session),
-                          self.repo.sources_by_uri['system'])
-
-    def test_source_from_eid_raise(self):
-        self.session.set_cnxset()
-        self.assertRaises(UnknownEid, self.repo.source_from_eid, -2, self.session)
-
     def test_type_from_eid(self):
         self.session.set_cnxset()
         self.assertEqual(self.repo.type_from_eid(2, self.session), 'CWGroup')
@@ -695,8 +684,7 @@
         self.repo.add_info(self.session, entity, self.repo.system_source)
         cu = self.session.system_sql('SELECT * FROM entities WHERE eid = -1')
         data = cu.fetchall()
-        self.assertEqual(tuplify(data), [(-1, 'Personne', 'system', 'system',
-                                          None)])
+        self.assertEqual(tuplify(data), [(-1, 'Personne', 'system', None)])
         self.repo.delete_info(self.session, entity, 'system')
         #self.repo.commit()
         cu = self.session.system_sql('SELECT * FROM entities WHERE eid = -1')

--- a/sobjects/supervising.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/sobjects/supervising.py	Thu Jan 23 13:47:28 2014 +0100
@@ -145,7 +145,7 @@
         session = self._cw
         def describe(eid):
             try:
-                return session._(session.describe(eid)[0]).lower()
+                return session._(session.entity_metas(eid)['type']).lower()
             except UnknownEid:
                 # may occurs when an entity has been deleted from an external
                 # source and we're cleaning its relation

--- a/test/unittest_dbapi.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/test/unittest_dbapi.py	Thu Jan 23 13:47:28 2014 +0100
@@ -49,9 +49,12 @@
     def test_api(self):
         cnx = _repo_connect(self.repo, login='anon', password='anon')
         self.assertEqual(cnx.user(None).login, 'anon')
+        self.assertEqual({'type': u'CWSource', 'source': u'system', 'extid': None},
+                         cnx.entity_metas(1))
         self.assertEqual(cnx.describe(1), (u'CWSource', u'system', None))
         cnx.close()
         self.assertRaises(ProgrammingError, cnx.user, None)
+        self.assertRaises(ProgrammingError, cnx.entity_metas, 1)
         self.assertRaises(ProgrammingError, cnx.describe, 1)
 
     def test_shared_data_api(self):

--- a/web/request.py	Thu Jan 23 12:32:16 2014 +0100
+++ b/web/request.py	Thu Jan 23 13:47:28 2014 +0100
@@ -1052,10 +1052,11 @@
             self._ = self.__ = unicode
             self.pgettext = lambda x, y: unicode(y)
 
-    describe = _cnx_func('describe')
+    entity_metas = _cnx_func('entity_metas')
     source_defs = _cnx_func('source_defs')
     get_shared_data = _cnx_func('get_shared_data')
     set_shared_data = _cnx_func('set_shared_data')
+    describe = _cnx_func('describe') # deprecated XXX
 
     # server-side service call #################################################