[FIX] ir_sequence: do the FOR UPDATE NO WAIT only in the No-gap sequence.

bzr revid: vmt@openerp.com-20110928114229-1g6r5et5frj26wam

openerp/addons/base/ir/ir_sequence.py

@@ -153,7 +153,7 @@ class ir_sequence(openerp.osv.osv.osv):
         """
         # TODO there is no access rights check on the sequence itself.
         res = self._select_by_code_or_id(cr, uid, sequence_code_or_id,
-            code_or_id, context)
+            code_or_id, False, context)
 
         if not res:
             return False
@@ -164,6 +164,9 @@ class ir_sequence(openerp.osv.osv.osv):
                 """ % res['id'])
             res['number_next'] = cr.fetchone()
         else:
+            # Read again with FOR UPDATE NO WAIT.
+            res = self._select_by_code_or_id(cr, uid, sequence_code_or_id,
+                code_or_id, True, context)
             cr.execute("""
                 UPDATE ir_sequence
                 SET number_next=number_next+number_increment
@@ -187,7 +190,8 @@ class ir_sequence(openerp.osv.osv.osv):
         """
         return self.get_id(cr, uid, code, 'code', context)
 
-    def _select_by_code_or_id(self, cr, uid, sequence_code_or_id, code_or_id, context=None):
+    def _select_by_code_or_id(self, cr, uid, sequence_code_or_id, code_or_id,
+            for_update_no_wait, context=None):
         """ Read a sequence object.
 
         There is no access rights check on the sequence itself.
@@ -195,6 +199,7 @@ class ir_sequence(openerp.osv.osv.osv):
         assert code_or_id in ('code', 'id')
         res_company = self.pool.get('res.company')
         company_ids = res_company.search(cr, uid, [], context=context)
+        funw = 'FOR UPDATE NOWAIT' if for_update_no_wait else ''
         cr.execute("""
             SELECT id, number_next, prefix, suffix, padding, implementation
             FROM ir_sequence
@@ -203,8 +208,9 @@ class ir_sequence(openerp.osv.osv.osv):
               AND (company_id in %%s or company_id is NULL)
             ORDER BY company_id, id
             LIMIT 1
-            FOR UPDATE NOWAIT
-            """ % code_or_id, (sequence_code_or_id, tuple(company_ids)))
+            %s
+            """ % (code_or_id, funw),
+            (sequence_code_or_id, tuple(company_ids)))
         return cr.dictfetchone()
 
     def _create_sequence(self, cr, id, number_increment, number_next):

tests/test_ir_sequence.py

@@ -7,6 +7,7 @@
 #    > OPENERP_ADDONS_PATH='../../../addons/trunk' OPENERP_PORT=8069 \
 #      OPENERP_DATABASE=yy PYTHONPATH=../:. unit2 test_ir_sequence
 import os
+import psycopg2
 import time
 import unittest2
 import xmlrpclib
@@ -26,7 +27,8 @@ def registry(model):
 def cursor():
     return openerp.modules.registry.RegistryManager.get(DB).db.cursor()
 
-class test_ir_sequence(unittest2.TestCase):
+class test_ir_sequence_standard(unittest2.TestCase):
+    """ A few tests for a 'Standard' (i.e. PostgreSQL) sequence. """
 
     def test_ir_sequence_create(self):
         """ Try to create a sequence object. """
@@ -52,6 +54,76 @@ class test_ir_sequence(unittest2.TestCase):
         finally:
             cr.close()
 
+    def test_ir_sequence_draw(self):
+        """ Try to draw a number. """
+        cr = cursor()
+        try:
+            n = registry('ir.sequence').get(cr, ADMIN_USER_ID, 'test_sequence_type', {})
+            assert n
+            cr.commit()
+        finally:
+            cr.close()
+
+    def test_ir_sequence_draw_twice(self):
+        """ Try to draw a number from two transactions. """
+        cr0 = cursor()
+        cr1 = cursor()
+        try:
+            n0 = registry('ir.sequence').get(cr0, ADMIN_USER_ID, 'test_sequence_type', {})
+            assert n0
+            n1 = registry('ir.sequence').get(cr1, ADMIN_USER_ID, 'test_sequence_type', {})
+            assert n1
+            cr0.commit()
+            cr1.commit()
+        finally:
+            cr0.close()
+            cr1.close()
+
+class test_ir_sequence_no_gap(unittest2.TestCase):
+    """ Copy of the previous tests for a 'No gap' sequence. """
+
+    def test_ir_sequence_create_no_gap(self):
+        """ Try to create a sequence object. """
+        cr = cursor()
+        try:
+            d = dict(code='test_sequence_type_2', name='Test sequence type')
+            c = registry('ir.sequence.type').create(cr, ADMIN_USER_ID, d, {})
+            assert c
+            d = dict(code='test_sequence_type_2', name='Test sequence',
+                implementation='no_gap')
+            c = registry('ir.sequence').create(cr, ADMIN_USER_ID, d, {})
+            assert c
+            cr.commit()
+        finally:
+            cr.close()
+
+    def test_ir_sequence_draw_no_gap(self):
+        """ Try to draw a number. """
+        cr = cursor()
+        try:
+            n = registry('ir.sequence').get(cr, ADMIN_USER_ID, 'test_sequence_type_2', {})
+            assert n
+            cr.commit()
+        finally:
+            cr.close()
+
+    def test_ir_sequence_draw_twice_no_gap(self):
+        """ Try to draw a number from two transactions.
+        This is expected to not work.
+        """
+        cr0 = cursor()
+        cr1 = cursor()
+        try:
+            msg_re = '^could not obtain lock on row in relation "ir_sequence"$'
+            with self.assertRaisesRegexp(psycopg2.OperationalError, msg_re):
+                n0 = registry('ir.sequence').get(cr0, ADMIN_USER_ID, 'test_sequence_type_2', {})
+                assert n0
+                n1 = registry('ir.sequence').get(cr1, ADMIN_USER_ID, 'test_sequence_type_2', {})
+        finally:
+            cr0.close()
+            cr1.close()
+
+
 if __name__ == '__main__':
     unittest2.main()