Add requestBodies scope support for OpenAPI (#2716)

* Add requestBodies scope support for OpenAPI

* fix: improve requestBodies schema parsing by skipping empty schemas

Author: koxudaxi

src/datamodel_code_generator/__init__.py

@@ -243,6 +243,7 @@ class OpenAPIScope(Enum):
     Tags = "tags"
     Parameters = "parameters"
     Webhooks = "webhooks"
+    RequestBodies = "requestbodies"
 
 
 class AllExportsScope(Enum):

src/datamodel_code_generator/parser/openapi.py

@@ -819,6 +819,29 @@ def parse_raw(self) -> None:
                 webhooks: dict[str, dict[str, Any]] = specification.get("webhooks", {})
                 self._process_path_items(webhooks, path_parts, "webhooks", [], security, strip_leading_slash=False)
 
+            if OpenAPIScope.RequestBodies in self.open_api_scopes:
+                request_bodies: dict[str, Any] = specification.get("components", {}).get("requestBodies", {})
+                for body_name, raw_body in request_bodies.items():
+                    resolved_body = self.get_ref_model(raw_body["$ref"]) if "$ref" in raw_body else raw_body
+                    content = resolved_body.get("content", {})
+                    for media_type, media_obj in content.items():
+                        schema = media_obj.get("schema")
+                        if not schema:
+                            continue
+                        self.parse_raw_obj(
+                            body_name,
+                            schema,
+                            [
+                                *path_parts,
+                                "#/components",
+                                "requestBodies",
+                                body_name,
+                                "content",
+                                media_type,
+                                "schema",
+                            ],
+                        )
+
         self._resolve_unparsed_json_pointer()
 
     def _collect_discriminator_schemas(self) -> None:

tests/data/expected/main/openapi/request_bodies_scope.py

@@ -0,0 +1,20 @@
+# generated by datamodel-codegen:
+#   filename:  request_bodies_scope.yaml
+#   timestamp: 1985-10-26T08:21:00+00:00
+
+from __future__ import annotations
+
+from pydantic import BaseModel, RootModel
+
+
+class CreatePet(BaseModel):
+    name: str | None = None
+    age: int | None = None
+
+
+class PetUpdate(BaseModel):
+    name: str | None = None
+
+
+class UpdatePet(RootModel[PetUpdate]):
+    root: PetUpdate

tests/data/expected/main/openapi/request_bodies_scope_with_ref.py

@@ -0,0 +1,15 @@
+# generated by datamodel-codegen:
+#   filename:  request_bodies_scope_with_ref.yaml
+#   timestamp: 1985-10-26T08:21:00+00:00
+
+from __future__ import annotations
+
+from pydantic import BaseModel
+
+
+class CreatePet(BaseModel):
+    name: str | None = None
+
+
+class BasePet(BaseModel):
+    name: str | None = None

tests/data/openapi/request_bodies_scope.yaml

@@ -0,0 +1,35 @@
+openapi: "3.0.0"
+info:
+  version: 1.0.0
+  title: Test API for RequestBodies Scope
+paths: {}
+components:
+  requestBodies:
+    CreatePet:
+      description: Request body for creating a pet
+      required: true
+      content:
+        application/json:
+          schema:
+            type: object
+            properties:
+              name:
+                type: string
+              age:
+                type: integer
+    UpdatePet:
+      description: Request body for updating a pet
+      content:
+        application/json:
+          schema:
+            $ref: '#/components/schemas/PetUpdate'
+    EmptyContent:
+      description: Request body with no schema
+      content:
+        application/json: {}
+  schemas:
+    PetUpdate:
+      type: object
+      properties:
+        name:
+          type: string

tests/data/openapi/request_bodies_scope_empty.yaml

@@ -0,0 +1,13 @@
+openapi: "3.0.0"
+info:
+  version: 1.0.0
+  title: Test API with empty requestBodies
+paths: {}
+components:
+  requestBodies: {}
+  schemas:
+    Pet:
+      type: object
+      properties:
+        name:
+          type: string

tests/data/openapi/request_bodies_scope_with_ref.yaml

@@ -0,0 +1,19 @@
+openapi: "3.0.0"
+info:
+  version: 1.0.0
+  title: Test API for RequestBodies with $ref
+paths: {}
+components:
+  requestBodies:
+    CreatePet:
+      $ref: '#/components/requestBodies/BasePet'
+    BasePet:
+      description: Base pet request body
+      required: true
+      content:
+        application/json:
+          schema:
+            type: object
+            properties:
+              name:
+                type: string

tests/main/openapi/test_main_openapi.py

@@ -4291,3 +4291,29 @@ def test_main_openapi_use_status_code_in_response_name(output_file: Path) -> Non
         expected_file="use_status_code_in_response_name.py",
         extra_args=["--use-status-code-in-response-name", "--openapi-scopes", "schemas", "paths"],
     )
+
+
+@freeze_time(TIMESTAMP)
+def test_main_openapi_request_bodies_scope(output_file: Path) -> None:
+    """Test generating models from components/requestBodies using requestbodies scope."""
+    run_main_and_assert(
+        input_path=OPEN_API_DATA_PATH / "request_bodies_scope.yaml",
+        output_path=output_file,
+        input_file_type="openapi",
+        assert_func=assert_file_content,
+        expected_file="request_bodies_scope.py",
+        extra_args=["--openapi-scopes", "requestbodies", "--output-model-type", "pydantic_v2.BaseModel"],
+    )
+
+
+@freeze_time(TIMESTAMP)
+def test_main_openapi_request_bodies_scope_with_ref(output_file: Path) -> None:
+    """Test generating models from components/requestBodies with $ref at requestBody level."""
+    run_main_and_assert(
+        input_path=OPEN_API_DATA_PATH / "request_bodies_scope_with_ref.yaml",
+        output_path=output_file,
+        input_file_type="openapi",
+        assert_func=assert_file_content,
+        expected_file="request_bodies_scope_with_ref.py",
+        extra_args=["--openapi-scopes", "requestbodies", "--output-model-type", "pydantic_v2.BaseModel"],
+    )

tests/parser/test_openapi.py

@@ -975,3 +975,62 @@ def test_parse_all_parameters_strict_nullable() -> None:
     assert len(fields) == 2
     assert fields[0].nullable is True
     assert fields[1].nullable is False
+
+
+def test_openapi_parser_with_request_bodies_scope() -> None:
+    """Test parsing OpenAPI with requestBodies scope generates models from components/requestBodies."""
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "request_bodies_scope.yaml"),
+        openapi_scopes=[OpenAPIScope.RequestBodies],
+    )
+    result = parser.parse()
+    assert "CreatePet" in result
+    assert "name: Optional[str]" in result
+    assert "age: Optional[int]" in result
+
+
+def test_openapi_parser_with_request_bodies_scope_ref() -> None:
+    """Test parsing OpenAPI with requestBodies scope handles $ref in schema."""
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "request_bodies_scope.yaml"),
+        openapi_scopes=[OpenAPIScope.RequestBodies, OpenAPIScope.Schemas],
+    )
+    result = parser.parse()
+    assert "UpdatePet" in result
+    assert "PetUpdate" in result
+
+
+def test_openapi_parser_with_request_bodies_scope_empty() -> None:
+    """Test parsing OpenAPI with requestBodies scope when requestBodies is empty."""
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "request_bodies_scope_empty.yaml"),
+        openapi_scopes=[OpenAPIScope.RequestBodies],
+    )
+    result = parser.parse()
+    assert result in ({}, "")
+
+
+def test_openapi_parser_with_request_bodies_scope_no_schema() -> None:
+    """Test parsing OpenAPI with requestBodies scope skips content without schema."""
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "request_bodies_scope.yaml"),
+        openapi_scopes=[OpenAPIScope.RequestBodies],
+    )
+    result = parser.parse()
+    assert "EmptyContent" not in result
+
+
+def test_openapi_parser_with_request_bodies_scope_body_ref() -> None:
+    """Test parsing OpenAPI with requestBodies scope handles $ref at requestBody level."""
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "request_bodies_scope_with_ref.yaml"),
+        openapi_scopes=[OpenAPIScope.RequestBodies],
+    )
+    result = parser.parse()
+    assert "CreatePet" in result or "BasePet" in result
+    assert "name: Optional[str]" in result