Use Pydantic for json serialization in .to_json method (#23210)

* [Python] Use pydantic_core.to_jsonable_python to convert non-standard data types

* [Python] Add test for UUID serialization

* update python samples

---------

Co-authored-by: Espen Haugsdal <espen.haugsdal@gmail.com>

Author: wing328

modules/openapi-generator/src/main/resources/python/model_generic.mustache

@@ -11,6 +11,7 @@ import json
 {{/vendorExtensions.x-py-model-imports}}
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 {{#hasChildren}}
 {{#discriminator}}
@@ -128,8 +129,7 @@ class {{classname}}({{#parent}}{{{.}}}{{/parent}}{{^parent}}BaseModel{{/parent}}
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[{{^hasChildren}}Self{{/hasChildren}}{{#hasChildren}}{{#discriminator}}Union[{{#mappedModels}}{{{modelName}}}{{^-last}}, {{/-last}}{{/mappedModels}}]{{/discriminator}}{{^discriminator}}Self{{/discriminator}}{{/hasChildren}}]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/bird.py

@@ -22,6 +22,7 @@
 from typing import Any, ClassVar, Dict, List, Optional
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class Bird(BaseModel):
     """
@@ -45,8 +46,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/category.py

@@ -22,6 +22,7 @@
 from typing import Any, ClassVar, Dict, List, Optional
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class Category(BaseModel):
     """
@@ -45,8 +46,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/data_query.py

@@ -24,6 +24,7 @@
 from openapi_client.models.query import Query
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class DataQuery(Query):
     """
@@ -48,8 +49,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/default_value.py

@@ -23,6 +23,7 @@
 from openapi_client.models.string_enum_ref import StringEnumRef
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class DefaultValue(BaseModel):
     """
@@ -63,8 +64,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/number_properties_only.py

@@ -23,6 +23,7 @@
 from typing_extensions import Annotated
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class NumberPropertiesOnly(BaseModel):
     """
@@ -47,8 +48,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/pet.py

@@ -24,6 +24,7 @@
 from openapi_client.models.tag import Tag
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class Pet(BaseModel):
     """
@@ -61,8 +62,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/query.py

@@ -22,6 +22,7 @@
 from typing import Any, ClassVar, Dict, List, Optional
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class Query(BaseModel):
     """
@@ -56,8 +57,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/tag.py

@@ -22,6 +22,7 @@
 from typing import Any, ClassVar, Dict, List, Optional
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class Tag(BaseModel):
     """
@@ -45,8 +46,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]:

samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/models/test_form_object_multipart_request_marker.py

@@ -22,6 +22,7 @@
 from typing import Any, ClassVar, Dict, List, Optional
 from typing import Optional, Set
 from typing_extensions import Self
+from pydantic_core import to_jsonable_python
 
 class TestFormObjectMultipartRequestMarker(BaseModel):
     """
@@ -44,8 +45,7 @@ def to_str(self) -> str:
 
     def to_json(self) -> str:
         """Returns the JSON representation of the model using alias"""
-        # TODO: pydantic v2: use .model_dump_json(by_alias=True, exclude_unset=True) instead
-        return json.dumps(self.to_dict())
+        return json.dumps(to_jsonable_python(self.to_dict()))
 
     @classmethod
     def from_json(cls, json_str: str) -> Optional[Self]: