CDK: improve TypeTransformer to convert simple types to array of simple types

airbyte-cdk/python/CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changelog
 
 ## 0.1.86
+- TypeTransformer now converts simple types to array of simple types
 - TypeTransformer make warning message more informative
 
 ## 0.1.85

airbyte-cdk/python/airbyte_cdk/sources/utils/transform.py

@@ -9,7 +9,8 @@
 
 from jsonschema import Draft7Validator, ValidationError, validators
 
-json_to_python = {"string": str, "number": float, "integer": int, "boolean": bool, "null": type(None), "object": dict, "array": list}
+json_to_python_simple = {"string": str, "number": float, "integer": int, "boolean": bool, "null": type(None)}
+json_to_python = json_to_python_simple | {"object": dict, "array": list}
 python_to_json = {v: k for k, v in json_to_python.items()}
 
 logger = logging.getLogger("airbyte")
@@ -117,6 +118,10 @@ def default_convert(original_item: Any, subschema: Dict[str, Any]) -> Any:
                 if isinstance(original_item, str):
                     return strtobool(original_item) == 1
                 return bool(original_item)
+            elif target_type == "array":
+                item_types = set(subschema.get("items", {}).get("type", set()))
+                if item_types.issubset(json_to_python_simple) and type(original_item) in json_to_python_simple.values():
+                    return [original_item]
         except (ValueError, TypeError):
             return original_item
         return original_item

airbyte-cdk/python/unit_tests/sources/utils/test_transform.py

@@ -114,8 +114,44 @@
             # Array without items and value is not an array
             {"type": "object", "properties": {"value": {"type": "array"}}},
             {"value": "12"},
-            {"value": "12"},
-            "Failed to transform value '12' of type 'string' to 'array', key path: '.value'",
+            {"value": ["12"]},
+            None,
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": "array"}}},
+            {"value": 12},
+            {"value": [12]},
+            None,
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": "array"}}},
+            {"value": None},
+            {"value": [None]},
+            None,
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": ["null", "array"]}}},
+            {"value": None},
+            {"value": None},
+            None,
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": "array", "items": {"type": ["string"]}}}},
+            {"value": 10},
+            {"value": ["10"]},
+            None,
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": "array", "items": {"type": ["object"]}}}},
+            {"value": "string"},
+            {"value": "string"},
+            "Failed to transform value 'string' of type 'string' to 'array', key path: '.value'",
+        ),
+        (
+            {"type": "object", "properties": {"value": {"type": "array", "items": {"type": ["string"]}}}},
+            {"value": {"key": "value"}},
+            {"value": {"key": "value"}},
+            "Failed to transform value {'key': 'value'} of type 'object' to 'array', key path: '.value'",
         ),
         (
             # Schema root object is not an object, no convertion should happen