Fixed JSON casts 😄

Author: Sibyx

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.12.1 : 2022-05-10
+
+- **Fixed**: Corrected cast of JSON fields
+
 ## 0.12.0 : 2021-12-21
 
 - **Feature**: `FirstValue` window function introduced

duckql/properties/property.py

@@ -17,6 +17,9 @@ class Config:
             'description': "Object representation of SQL column/property"
         }
 
+    def is_json_field(self) -> bool:
+        return '->>' in self.name or '->' in self.name
+
     def to_sql(self) -> str:
         if '->>' in self.name or '->' in self.name:
             sql = ''

duckql/structures/cast_operator.py

@@ -40,7 +40,10 @@ class DataType(Enum):
     alias: str = None
 
     def to_sql(self) -> str:
-        sql = f"{self.property}::{self.to.value}"
+        if isinstance(self.property, Property) and self.property.is_json_field():
+            sql = f"({self.property})::{self.to.value}"
+        else:
+            sql = f"{self.property}::{self.to.value}"
 
         if self.alias is not None:
             sql = f"{sql} AS {self.alias}"

duckql/structures/tests/test_cast_operator.py

@@ -10,3 +10,13 @@ def test_simple():
     )
 
     assert str(my_structure) == 'users.age::varchar AS age_as_string'
+
+
+def test_json_field():
+    my_structure = CastOperator(
+        property=Property(name='organisations.statistics->campaigns_count'),
+        to=CastOperator.DataType.INT,
+        alias='campaigns_count'
+    )
+
+    assert str(my_structure) == '(organisations.statistics ->> \'campaigns_count\')::int AS campaigns_count'

duckql/version.py

@@ -1 +1 @@
-__version__ = '0.12.0'
+__version__ = '0.12.1'