Allow including path parameters in generated models (#2445)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: MrLoh

README.md

@@ -502,6 +502,9 @@ Template customization:
                         option (require black 20.8b0 or later)
 
 OpenAPI-only options:
+  --include-path-parameters
+                        Include path parameters in generated parameter models in addition to
+                        query parameters (Only OpenAPI)
   --openapi-scopes {schemas,paths,tags,parameters} [{schemas,paths,tags,parameters} ...]
                         Scopes of OpenAPI model generation (default: schemas)
   --strict-nullable     Treat default field as a non-nullable field (Only OpenAPI)

docs/index.md

@@ -494,6 +494,9 @@ Template customization:
                         option (require black 20.8b0 or later)
 
 OpenAPI-only options:
+  --include-path-parameters
+                        Include path parameters in generated parameter models in addition to
+                        query parameters (Only OpenAPI)
   --openapi-scopes {schemas,paths,tags,parameters} [{schemas,paths,tags,parameters} ...]
                         Scopes of OpenAPI model generation (default: schemas)
   --strict-nullable     Treat default field as a non-nullable field (Only OpenAPI)

src/datamodel_code_generator/__init__.py

@@ -258,6 +258,7 @@ def generate(  # noqa: PLR0912, PLR0913, PLR0914, PLR0915
     field_include_all_keys: bool = False,
     field_extra_keys_without_x_prefix: set[str] | None = None,
     openapi_scopes: list[OpenAPIScope] | None = None,
+    include_path_parameters: bool = False,
     graphql_scopes: list[GraphQLScope] | None = None,  # noqa: ARG001
     wrap_string_literal: bool | None = None,
     use_title_as_name: bool = False,
@@ -327,6 +328,7 @@ def generate(  # noqa: PLR0912, PLR0913, PLR0914, PLR0915
 
         parser_class: type[Parser] = OpenAPIParser
         kwargs["openapi_scopes"] = openapi_scopes
+        kwargs["include_path_parameters"] = include_path_parameters
     elif input_file_type == InputFileType.GraphQL:
         from datamodel_code_generator.parser.graphql import GraphQLParser  # noqa: PLC0415
 

src/datamodel_code_generator/__main__.py

@@ -287,6 +287,7 @@ def validate_root(cls, values: Any) -> Any:  # noqa: N805
     field_include_all_keys: bool = False
     field_extra_keys_without_x_prefix: Optional[set[str]] = None  # noqa: UP045
     openapi_scopes: Optional[list[OpenAPIScope]] = [OpenAPIScope.Schemas]  # noqa: UP045
+    include_path_parameters: bool = False
     wrap_string_literal: Optional[bool] = None  # noqa: UP045
     use_title_as_name: bool = False
     use_operation_id_as_name: bool = False
@@ -500,6 +501,7 @@ def main(args: Sequence[str] | None = None) -> Exit:  # noqa: PLR0911, PLR0912,
             field_include_all_keys=config.field_include_all_keys,
             field_extra_keys_without_x_prefix=config.field_extra_keys_without_x_prefix,
             openapi_scopes=config.openapi_scopes,
+            include_path_parameters=config.include_path_parameters,
             wrap_string_literal=config.wrap_string_literal,
             use_title_as_name=config.use_title_as_name,
             use_operation_id_as_name=config.use_operation_id_as_name,

src/datamodel_code_generator/arguments.py

@@ -500,6 +500,12 @@ def start_section(self, heading: str | None) -> None:
     action="store_true",
     default=None,
 )
+openapi_options.add_argument(
+    "--include-path-parameters",
+    help="Include path parameters in generated parameter models in addition to query parameters (Only OpenAPI)",
+    action="store_true",
+    default=None,
+)
 openapi_options.add_argument(
     "--validation",
     help="Deprecated: Enable validation (Only OpenAPI). this option is deprecated. it will be removed in future "

src/datamodel_code_generator/parser/openapi.py

@@ -189,6 +189,7 @@ def __init__(  # noqa: PLR0913
         field_include_all_keys: bool = False,
         field_extra_keys_without_x_prefix: set[str] | None = None,
         openapi_scopes: list[OpenAPIScope] | None = None,
+        include_path_parameters: bool = False,
         wrap_string_literal: bool | None = False,
         use_title_as_name: bool = False,
         use_operation_id_as_name: bool = False,
@@ -299,6 +300,7 @@ def __init__(  # noqa: PLR0913
             parent_scoped_naming=parent_scoped_naming,
         )
         self.open_api_scopes: list[OpenAPIScope] = openapi_scopes or [OpenAPIScope.Schemas]
+        self.include_path_parameters: bool = include_path_parameters
 
     def get_ref_model(self, ref: str) -> dict[str, Any]:
         ref_file, ref_path = self.model_resolver.resolve_ref(ref).split("#", 1)
@@ -421,8 +423,17 @@ def parse_all_parameters(
         for parameter_ in parameters:
             parameter = self.resolve_object(parameter_, ParameterObject)
             parameter_name = parameter.name
-            if not parameter_name or parameter.in_ != ParameterLocation.query:
+            if (
+                not parameter_name
+                or parameter.in_ not in {ParameterLocation.query, ParameterLocation.path}
+                or (parameter.in_ == ParameterLocation.path and not self.include_path_parameters)
+            ):
                 continue
+
+            if any(field.original_name == parameter_name for field in fields):
+                msg = f"Parameter name '{parameter_name}' is used more than once."
+                raise Exception(msg)  # noqa: TRY002
+
             field_name, alias = self.model_resolver.get_valid_field_name_and_alias(
                 field_name=parameter_name, excludes=exclude_field_names
             )
@@ -518,7 +529,9 @@ def parse_operation(
             path_name = operation.operationId
             method = ""
         self.parse_all_parameters(
-            self._get_model_name(path_name, method, suffix="ParametersQuery"),
+            self._get_model_name(
+                path_name, method, suffix="Parameters" if self.include_path_parameters else "ParametersQuery"
+            ),
             operation.parameters,
             [*path, "parameters"],
         )

tests/data/expected/parser/openapi/openapi_parser_with_query_parameters/output.py

@@ -22,6 +22,10 @@ class PetForm(BaseModel):
     age: Optional[int] = None
 
 
+class PetsPetIdGetParametersQuery(BaseModel):
+    include: Optional[str] = None
+
+
 class Filter(BaseModel):
     type: Optional[str] = None
     color: Optional[str] = None

tests/data/expected/parser/openapi/openapi_parser_with_query_parameters/with_path_params.py

@@ -0,0 +1,66 @@
+from __future__ import annotations
+
+from enum import Enum
+from typing import List, Optional, Union
+
+from pydantic import BaseModel
+
+
+class Pet(BaseModel):
+    id: int
+    name: str
+    tag: Optional[str] = None
+
+
+class Error(BaseModel):
+    code: int
+    message: str
+
+
+class PetForm(BaseModel):
+    name: Optional[str] = None
+    age: Optional[int] = None
+
+
+class PetsPetIdGetParameters(BaseModel):
+    petId: str
+    include: Optional[str] = None
+
+
+class Filter(BaseModel):
+    type: Optional[str] = None
+    color: Optional[str] = None
+
+
+class MediaType(Enum):
+    xml = 'xml'
+    json = 'json'
+
+
+class MultipleMediaFilter(BaseModel):
+    type: Optional[str] = None
+    media_type: Optional[MediaType] = 'xml'
+
+
+class MultipleMediaFilter1(BaseModel):
+    type: Optional[str] = None
+    media_type: Optional[MediaType] = 'json'
+
+
+class PetsGetParameters(BaseModel):
+    limit: Optional[int] = 0
+    HomeAddress: Optional[str] = 'Unknown'
+    kind: Optional[str] = 'dog'
+    filter: Optional[Filter] = None
+    multipleMediaFilter: Optional[
+        Union[MultipleMediaFilter, MultipleMediaFilter1]
+    ] = None
+
+
+class PetsGetResponse(BaseModel):
+    __root__: List[Pet]
+
+
+class PetsPostRequest(BaseModel):
+    name: Optional[str] = None
+    age: Optional[int] = None

tests/data/openapi/query_parameters.yaml

@@ -14,6 +14,30 @@ servers:
 security:
   - BearerAuth: []
 paths:
+  /pets/{petId}:
+    get:
+      summary: Get a pet by ID
+      operationId: getPet
+      parameters:
+        - name: petId
+          in: path
+          required: true
+          description: The pet ID
+          schema:
+            type: string
+        - name: include
+          in: query
+          required: false
+          description: Include additional data
+          schema:
+            type: string
+      responses:
+        '200':
+          description: A pet
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Pet"
   /pets:
     get:
       summary: List all pets

tests/parser/test_openapi.py

@@ -15,7 +15,7 @@
 from datamodel_code_generator.model.pydantic import DataModelField
 from datamodel_code_generator.parser.base import dump_templates
 from datamodel_code_generator.parser.jsonschema import JsonSchemaObject
-from datamodel_code_generator.parser.openapi import OpenAPIParser
+from datamodel_code_generator.parser.openapi import OpenAPIParser, ParameterObject
 
 DATA_PATH: Path = Path(__file__).parents[1] / "data" / "openapi"
 
@@ -668,6 +668,40 @@ def test_openapi_parser_with_query_parameters() -> None:
     assert parser.parse() == (EXPECTED_OPEN_API_PATH / "openapi_parser_with_query_parameters" / "output.py").read_text()
 
 
+@pytest.mark.skipif(
+    black.__version__.split(".")[0] >= "24",
+    reason="Installed black doesn't support the old style",
+)
+def test_openapi_parser_with_include_path_parameters() -> None:
+    parser = OpenAPIParser(
+        data_model_field_type=DataModelFieldBase,
+        source=Path(DATA_PATH / "query_parameters.yaml"),
+        openapi_scopes=[
+            OpenAPIScope.Parameters,
+            OpenAPIScope.Schemas,
+            OpenAPIScope.Paths,
+        ],
+        include_path_parameters=True,
+    )
+    assert (
+        parser.parse()
+        == (EXPECTED_OPEN_API_PATH / "openapi_parser_with_query_parameters" / "with_path_params.py").read_text()
+    )
+
+
+def test_parse_all_parameters_duplicate_names_exception() -> None:
+    parser = OpenAPIParser("", include_path_parameters=True)
+    parameters = [
+        ParameterObject.parse_obj({"name": "duplicate_param", "in": "path", "schema": {"type": "string"}}),
+        ParameterObject.parse_obj({"name": "duplicate_param", "in": "query", "schema": {"type": "integer"}}),
+    ]
+
+    with pytest.raises(Exception) as exc_info:  # noqa: PT011
+        parser.parse_all_parameters("TestModel", parameters, ["test", "path"])
+
+    assert "Parameter name 'duplicate_param' is used more than once." in str(exc_info.value)
+
+
 @pytest.mark.skipif(
     version.parse(pydantic.VERSION) < version.parse("2.9.0"),
     reason="Require Pydantic version 2.0.0 or later ",