Add has_select_for on Database

- Use has_select_for for ir.sequence.strict instead of lock

issue6134
review32911002

CHANGELOG

@@ -1,3 +1,4 @@
+* Add has_select_for on Database
 * Store custom report translation in separate module
 * Add form action keyword for set/synchronize translation on report and view
 * Add negative value for col attribute

trytond/backend/database.py

@@ -151,3 +151,7 @@ class DatabaseInterface(object):
     def has_multirow_insert(self):
         'Return True if database supports multirow insert'
         return False
+
+    def has_select_for(self):
+        "Return if database supports FOR UPDATE/SHARE clause in SELECT."
+        return False

trytond/backend/postgresql/database.py

@@ -295,6 +295,9 @@ class Database(DatabaseInterface):
                 self.put_connection(connection)
         return self._has_returning
 
+    def has_select_for(self):
+        return True
+
 register_type(UNICODE)
 if PYDATE:
     register_type(PYDATE)

trytond/ir/sequence.py

@@ -3,7 +3,7 @@
 from string import Template
 import time
 from itertools import izip
-from sql import Flavor
+from sql import Flavor, Literal, For
 
 from ..model import ModelView, ModelSQL, fields, Check
 from ..tools import datetime_strftime
@@ -354,7 +354,7 @@ class Sequence(ModelSQL, ModelView):
         return ''
 
     @classmethod
-    def get_id(cls, domain):
+    def get_id(cls, domain, _lock=False):
         '''
         Return sequence value for the domain
         '''
@@ -370,6 +370,19 @@ class Sequence(ModelSQL, ModelView):
                     sequence, = cls.search(domain, limit=1)
                 except TypeError:
                     cls.raise_user_error('missing')
+                if _lock:
+                    transaction = Transaction()
+                    database = transaction.database
+                    connection = transaction.connection
+                    if not database.has_select_for():
+                        database.lock(connection, cls._table)
+                    else:
+                        table = cls.__table__()
+                        query = table.select(Literal(1),
+                            where=table.id == sequence.id,
+                            for_=For('UPDATE', nowait=True))
+                        cursor = connection.cursor()
+                        cursor.execute(*query)
                 date = Transaction().context.get('date')
                 return '%s%s%s' % (
                     cls._process(sequence.prefix, date=date),
@@ -390,6 +403,4 @@ class SequenceStrict(Sequence):
 
     @classmethod
     def get_id(cls, clause):
-        transaction = Transaction()
-        transaction.database.lock(transaction.connection, cls._table)
-        return super(SequenceStrict, cls).get_id(clause)
+        return super(SequenceStrict, cls).get_id(clause, _lock=True)

trytond/tests/test_sequence.py

@@ -16,11 +16,15 @@ class SequenceTestCase(unittest.TestCase):
     def setUpClass(cls):
         activate_module('tests')
 
+    @staticmethod
+    def get_model():
+        pool = Pool()
+        return pool.get('ir.sequence')
+
     @with_transaction()
     def test_incremental(self):
         'Test incremental'
-        pool = Pool()
-        Sequence = pool.get('ir.sequence')
+        Sequence = self.get_model()
 
         sequence, = Sequence.create([{
                     'name': 'Test incremental',
@@ -48,8 +52,7 @@ class SequenceTestCase(unittest.TestCase):
     @with_transaction()
     def test_decimal_timestamp(self):
         'Test Decimal Timestamp'
-        pool = Pool()
-        Sequence = pool.get('ir.sequence')
+        Sequence = self.get_model()
 
         sequence, = Sequence.create([{
                     'name': 'Test decimal timestamp',
@@ -73,8 +76,7 @@ class SequenceTestCase(unittest.TestCase):
     @with_transaction()
     def test_hexadecimal_timestamp(self):
         'Test Hexadecimal Timestamp'
-        pool = Pool()
-        Sequence = pool.get('ir.sequence')
+        Sequence = self.get_model()
 
         sequence, = Sequence.create([{
                     'name': 'Test hexadecimal timestamp',
@@ -99,8 +101,7 @@ class SequenceTestCase(unittest.TestCase):
     @with_transaction()
     def test_prefix_suffix(self):
         'Test prefix/suffix'
-        pool = Pool()
-        Sequence = pool.get('ir.sequence')
+        Sequence = self.get_model()
 
         sequence, = Sequence.create([{
                     'name': 'Test incremental',
@@ -121,5 +122,19 @@ class SequenceTestCase(unittest.TestCase):
                 '2010-08-15/2/15.08.2010')
 
 
+class SequenceStrictTestCase(SequenceTestCase):
+    "Test Sequence Strict"
+
+    @staticmethod
+    def get_model():
+        pool = Pool()
+        return pool.get('ir.sequence.strict')
+
+
 def suite():
-    return unittest.TestLoader().loadTestsFromTestCase(SequenceTestCase)
+    suite_ = unittest.TestSuite()
+    suite_.addTests(unittest.TestLoader().loadTestsFromTestCase(
+            SequenceTestCase))
+    suite_.addTests(unittest.TestLoader().loadTestsFromTestCase(
+            SequenceStrictTestCase))
+    return suite_