Implement Decimal reflection (#74)

* Decimal parse support

clickhouse_sqlalchemy/__init__.py

@@ -4,7 +4,7 @@
 from .sql import Table, select
 
 
-VERSION = (0, 1, 2)
+VERSION = (0, 1, 3)
 __version__ = '.'.join(str(x) for x in VERSION)
 
 

clickhouse_sqlalchemy/drivers/base.py

@@ -35,6 +35,7 @@
     'DateTime': DATETIME,
     'Float64': FLOAT,
     'Float32': FLOAT,
+    'Decimal': types.Decimal,
     'String': types.String,
     'UUID': types.UUID,
     'IPv4': types.IPv4,
@@ -663,6 +664,9 @@ def _get_column_type(self, name, spec):
             type_enum = enum.Enum('%s_enum' % name, options)
             return lambda: coltype(type_enum)
 
+        elif spec.lower().startswith('decimal'):
+            coltype = self.ischema_names['Decimal']
+            return coltype(*self._parse_decimal_params(spec))
         else:
             try:
                 return self.ischema_names[spec]
@@ -671,6 +675,12 @@ def _get_column_type(self, name, spec):
                      (spec, name))
                 return sqltypes.NullType
 
+    @staticmethod
+    def _parse_decimal_params(spec):
+        ints = spec.split('(')[-1].split(')')[0]  # get all data in brackets
+        precision, scale = ints.split(',')
+        return int(precision.strip()), int(scale.strip())
+
     @staticmethod
     def _parse_options(option_string):
         options = dict()

tests/test_reflection.py

@@ -78,3 +78,10 @@ def test_enum16(self):
         self.assertEqual(
             {o.name: o.value for o in coltype.enum_class}, enum_options
         )
+
+    def test_decimal(self):
+        coltype = self._type_round_trip(types.Decimal(38, 38))[0]
+
+        self.assertIsInstance(coltype, types.Decimal)
+        self.assertEqual(coltype.precision, 38)
+        self.assertEqual(coltype.scale, 38)