Only convert dict fields when they are strings

issue6382
review28101002

CHANGELOG

@@ -1,3 +1,5 @@
+* Allow to store Dict as JSON on the database
+
 Version 4.4.0 - 2017-05-01
 * Bug fixes (see mercurial logs for details)
 * Sanitize path in file_open against suffix (CVE-2017-0360)

doc/ref/models/fields.rst

@@ -846,6 +846,10 @@ Dict
 
 A dictionary field with predefined keys.
 
+.. note::
+    It is possible to store the dict as JSON in the database if the backend
+    supports by manually altering the column type to JSON on the database.
+
 :class:`Dict` has one extra required argument:
 
 .. attribute:: Dict.schema_model

setup.py

@@ -33,9 +33,9 @@ if minor_version % 2:
         name, name, version)
 
 if platform.python_implementation() == 'PyPy':
-    pg_require = ['psycopg2cffi >= 2.5']
+    pg_require = ['psycopg2cffi >= 2.5.4']
 else:
-    pg_require = ['psycopg2 >= 2.5']
+    pg_require = ['psycopg2 >= 2.5.4']
 
 setup(name=name,
     version=version,

trytond/backend/postgresql/database.py

@@ -5,6 +5,7 @@ import logging
 import re
 import os
 import urllib
+import json
 from decimal import Decimal
 from threading import RLock
 
@@ -26,11 +27,13 @@ except ImportError:
     PYDATE, PYDATETIME, PYTIME, PYINTERVAL = None, None, None, None
 from psycopg2 import IntegrityError as DatabaseIntegrityError
 from psycopg2 import OperationalError as DatabaseOperationalError
+from psycopg2.extras import register_default_json, register_default_jsonb
 
 from sql import Flavor
 
 from trytond.backend.database import DatabaseInterface, SQLType
 from trytond.config import config, parse_uri
+from trytond.protocols.jsonrpc import JSONDecoder
 
 __all__ = ['Database', 'DatabaseIntegrityError', 'DatabaseOperationalError']
 
@@ -340,3 +343,9 @@ if PYINTERVAL:
     register_type(PYINTERVAL)
 register_adapter(float, lambda value: AsIs(repr(value)))
 register_adapter(Decimal, lambda value: AsIs(str(value)))
+
+
+def convert_json(value):
+    return json.loads(value, object_hook=JSONDecoder())
+register_default_json(loads=convert_json)
+register_default_jsonb(loads=convert_json)

trytond/model/fields/dict.py

@@ -25,9 +25,12 @@ class Dict(Field):
     def get(self, ids, model, name, values=None):
         dicts = dict((id, None) for id in ids)
         for value in values or []:
-            if value[name]:
-                dicts[value['id']] = json.loads(value[name],
-                    object_hook=JSONDecoder())
+            data = value[name]
+            if data:
+                # If stored as JSON conversion is done on backend
+                if isinstance(data, basestring):
+                    data = json.loads(data, object_hook=JSONDecoder())
+                dicts[value['id']] = data
         return dicts
 
     def sql_format(self, value):

trytond/tests/__init__.py

@@ -108,6 +108,7 @@ def register():
         Dict,
         DictDefault,
         DictRequired,
+        DictJSONB,
         Binary,
         BinaryDefault,
         BinaryRequired,

trytond/tests/test.py

@@ -39,7 +39,7 @@ __all__ = [
     'Many2ManyFilterDomainRelation',
     'Reference', 'ReferenceTarget', 'ReferenceRequired',
     'Selection', 'SelectionRequired',
-    'DictSchema', 'Dict', 'DictDefault', 'DictRequired',
+    'DictSchema', 'Dict', 'DictDefault', 'DictRequired', 'DictJSONB',
     'Binary', 'BinaryDefault', 'BinaryRequired', 'BinaryFileStorage',
     'Many2OneDomainValidation', 'Many2OneTarget', 'Many2OneOrderBy',
     'Many2OneSearch', 'Many2OneTree', 'Many2OneMPTT', 'Many2OneNoForeignKey',
@@ -782,6 +782,12 @@ class DictRequired(ModelSQL):
     dico = fields.Dict(None, 'Test Dict', required=True)
 
 
+class DictJSONB(ModelSQL):
+    'Dict JSONB'
+    __name__ = 'test.dict_jsonb'
+    dico = fields.Dict('test.dict.schema', 'Test Dict')
+
+
 class Binary(ModelSQL):
     'Binary'
     __name__ = 'test.binary'

trytond/tests/test_fields.py

@@ -21,6 +21,7 @@ from trytond.exceptions import UserError
 from trytond.model import fields
 from trytond.pool import Pool
 from trytond.config import config
+from trytond import backend
 
 
 class FieldsTestCase(unittest.TestCase):
@@ -3124,6 +3125,31 @@ class FieldsTestCase(unittest.TestCase):
         self.assertRaises(UserError, DictRequired.create,
             [{'dico': {}}])
 
+    @with_transaction()
+    @unittest.skipIf(
+        backend.name() != 'postgresql', 'jsonb only suported by postgresql')
+    def test_dict_jsonb(self):
+        'Test Dict stored as jsonb'
+        pool = Pool()
+        Dict = pool.get('test.dict_jsonb')
+        connection = Transaction().connection
+        cursor = connection.cursor()
+
+        Database = backend.get('Database')
+        if Database().get_version(connection) < (9, 2):
+            return
+
+        cursor.execute('ALTER TABLE "%s" '
+            'ALTER COLUMN dico TYPE json USING dico::json' % Dict._table)
+
+        dict1, = Dict.create([{
+                    'dico': {'a': 1, 'b': 2},
+                    }])
+        self.assert_(dict1.dico == {'a': 1, 'b': 2})
+
+        Dict.write([dict1], {'dico': {'z': 26}})
+        self.assert_(dict1.dico == {'z': 26})
+
     @with_transaction()
     def test_binary(self):
         'Test Binary'