fix: GenAI - Fixed from_dict methods

The parsing of dictionaries was standardized and improved. Parsing dictionaries via `json_formt.ParseDict` allows automatically handling renamed fields like `type_`, `format_`, `enum_` and also camelCase keys like `minItems` that are often used in Json Schema schemas. The `json_formt.ParseDict` method succeeds in such cases while the Proto Message constructors fail.

However there is an issue with enums which makes full migration to `json_schema.ParseDict` non-trivial. Protobuf's ParseDict treats enum names as case sensitive. This is mostly problematic for Shema messages where Python protos use uppercase enum names like `"OBJECT"` while Json Schemas usually use lowercase types like `"object"`. I've created a fix for the protobuf library, but it will take a while before it's released everywhere. So, enums need to be fixed. But such enums can happen in multiple places in a deeply nested dictionary structure. We need to carefully fix all enum casing issues in nested dicts before we can use `ParseDict`.

PiperOrigin-RevId: 680480143

Author: Ark-kun

vertexai/generative_models/_generative_models.py

@@ -32,6 +32,8 @@
     Literal,
     Optional,
     Sequence,
+    Type,
+    TypeVar,
     Union,
     overload,
     TYPE_CHECKING,
@@ -66,6 +68,10 @@
 except ImportError:
     PIL_Image = None
 
+
+T = TypeVar("T")
+
+
 # Re-exporting some GAPIC types
 
 # GAPIC types used in request
@@ -1627,8 +1633,9 @@ def __init__(
         if response_schema is None:
             raw_schema = None
         else:
-            gapic_schema_dict = _convert_schema_dict_to_gapic(response_schema)
-            raw_schema = aiplatform_types.Schema(gapic_schema_dict)
+            raw_schema = FunctionDeclaration(
+                name="tmp", parameters=response_schema
+            )._raw_function_declaration.parameters
         self._raw_generation_config = gapic_content_types.GenerationConfig(
             temperature=temperature,
             top_p=top_p,
@@ -1660,8 +1667,12 @@ def _from_gapic(
 
     @classmethod
     def from_dict(cls, generation_config_dict: Dict[str, Any]) -> "GenerationConfig":
-        raw_generation_config = gapic_content_types.GenerationConfig(
-            generation_config_dict
+        generation_config_dict = copy.deepcopy(generation_config_dict)
+        response_schema = generation_config_dict.get("response_schema")
+        if response_schema:
+            _fix_schema_dict_for_gapic_in_place(response_schema)
+        raw_generation_config = _dict_to_proto(
+            gapic_content_types.GenerationConfig, generation_config_dict
         )
         return cls._from_gapic(raw_generation_config=raw_generation_config)
 
@@ -1872,12 +1883,11 @@ def _from_gapic(
     @classmethod
     def from_dict(cls, tool_dict: Dict[str, Any]) -> "Tool":
         tool_dict = copy.deepcopy(tool_dict)
-        function_declarations = tool_dict["function_declarations"]
-        for function_declaration in function_declarations:
-            function_declaration["parameters"] = _convert_schema_dict_to_gapic(
-                function_declaration["parameters"]
-            )
-        raw_tool = gapic_tool_types.Tool(tool_dict)
+        for function_declaration in tool_dict.get("function_declarations") or []:
+            parameters = function_declaration.get("parameters")
+            if parameters:
+                _fix_schema_dict_for_gapic_in_place(parameters)
+        raw_tool = _dict_to_proto(aiplatform_types.Tool, tool_dict)
         return cls._from_gapic(raw_tool=raw_tool)
 
     def to_dict(self) -> Dict[str, Any]:
@@ -2035,8 +2045,9 @@ def __init__(
             description: Description and purpose of the function.
                 Model uses it to decide how and whether to call the function.
         """
-        gapic_schema_dict = _convert_schema_dict_to_gapic(parameters)
-        raw_schema = aiplatform_types.Schema(gapic_schema_dict)
+        parameters = copy.deepcopy(parameters)
+        _fix_schema_dict_for_gapic_in_place(parameters)
+        raw_schema = _dict_to_proto(aiplatform_types.Schema, parameters)
         self._raw_function_declaration = gapic_tool_types.FunctionDeclaration(
             name=name, description=description, parameters=raw_schema
         )
@@ -2052,6 +2063,7 @@ def __repr__(self) -> str:
         return self._raw_function_declaration.__repr__()
 
 
+# TODO: Remove this function once Reasoning Engines moves away from it.
 def _convert_schema_dict_to_gapic(schema_dict: Dict[str, Any]) -> Dict[str, Any]:
     """Converts a JsonSchema to a dict that the GAPIC Schema class accepts."""
     gapic_schema_dict = copy.copy(schema_dict)
@@ -2070,6 +2082,20 @@ def _convert_schema_dict_to_gapic(schema_dict: Dict[str, Any]) -> Dict[str, Any]
     return gapic_schema_dict
 
 
+def _fix_schema_dict_for_gapic_in_place(schema_dict: Dict[str, Any]) -> None:
+    """Converts a JsonSchema to a dict that the Schema proto class accepts."""
+    schema_dict["type"] = schema_dict["type"].upper()
+
+    items_schema = schema_dict.get("items")
+    if items_schema:
+        _fix_schema_dict_for_gapic_in_place(items_schema)
+
+    properties = schema_dict.get("properties")
+    if properties:
+        for property_schema in properties.values():
+            _fix_schema_dict_for_gapic_in_place(property_schema)
+
+
 class CallableFunctionDeclaration(FunctionDeclaration):
     """A function declaration plus a function."""
 
@@ -2139,8 +2165,9 @@ def _from_gapic(
 
     @classmethod
     def from_dict(cls, response_dict: Dict[str, Any]) -> "GenerationResponse":
-        raw_response = gapic_prediction_service_types.GenerateContentResponse()
-        json_format.ParseDict(response_dict, raw_response._pb)
+        raw_response = _dict_to_proto(
+            gapic_prediction_service_types.GenerateContentResponse, response_dict
+        )
         return cls._from_gapic(raw_response=raw_response)
 
     def to_dict(self) -> Dict[str, Any]:
@@ -2209,8 +2236,7 @@ def _from_gapic(cls, raw_candidate: gapic_content_types.Candidate) -> "Candidate
 
     @classmethod
     def from_dict(cls, candidate_dict: Dict[str, Any]) -> "Candidate":
-        raw_candidate = gapic_content_types.Candidate()
-        json_format.ParseDict(candidate_dict, raw_candidate._pb)
+        raw_candidate = _dict_to_proto(gapic_content_types.Candidate, candidate_dict)
         return cls._from_gapic(raw_candidate=raw_candidate)
 
     def to_dict(self) -> Dict[str, Any]:
@@ -2310,8 +2336,7 @@ def _from_gapic(cls, raw_content: gapic_content_types.Content) -> "Content":
 
     @classmethod
     def from_dict(cls, content_dict: Dict[str, Any]) -> "Content":
-        raw_content = gapic_content_types.Content()
-        json_format.ParseDict(content_dict, raw_content._pb)
+        raw_content = _dict_to_proto(gapic_content_types.Content, content_dict)
         return cls._from_gapic(raw_content=raw_content)
 
     def to_dict(self) -> Dict[str, Any]:
@@ -2381,8 +2406,7 @@ def _from_gapic(cls, raw_part: gapic_content_types.Part) -> "Part":
 
     @classmethod
     def from_dict(cls, part_dict: Dict[str, Any]) -> "Part":
-        raw_part = gapic_content_types.Part()
-        json_format.ParseDict(part_dict, raw_part._pb)
+        raw_part = _dict_to_proto(gapic_content_types.Part, part_dict)
         return cls._from_gapic(raw_part=raw_part)
 
     def __repr__(self) -> str:
@@ -2510,7 +2534,9 @@ def _from_gapic(
 
     @classmethod
     def from_dict(cls, safety_setting_dict: Dict[str, Any]) -> "SafetySetting":
-        raw_safety_setting = gapic_content_types.SafetySetting(safety_setting_dict)
+        raw_safety_setting = _dict_to_proto(
+            aiplatform_types.SafetySetting, safety_setting_dict
+        )
         return cls._from_gapic(raw_safety_setting=raw_safety_setting)
 
     def to_dict(self) -> Dict[str, Any]:
@@ -2760,6 +2786,15 @@ def _proto_to_dict(message) -> Dict[str, Any]:
     )
 
 
+def _dict_to_proto(message_type: Type[T], message_dict: Dict[str, Any]) -> T:
+    """Converts a dictionary to a proto-plus protobuf message."""
+    # We cannot just use `message = message_type(message_dict)` because
+    # it fails for classes where GAPIC has renamed proto fields.
+    message = message_type()
+    json_format.ParseDict(message_dict, message._pb)
+    return message
+
+
 def _dict_to_pretty_string(d: dict) -> str:
     """Format dict as a pretty-printed JSON string."""
     return json.dumps(d, indent=2)