Dict and any support (#58)

* Dict and any support

* Tweak changelog

* Fix tests

CHANGELOG.md

@@ -10,6 +10,15 @@ The **third number** is for emergencies when we need to start branches for older
 
 <!-- changelog follows -->
 
+## [v24.1.0](https://github.com/tinche/uapi/compare/v23.3.0...HEAD) - UNRELEASED
+
+### Added
+
+- `typing.Any` is now supported in the OpenAPI schema, rendering to an empty schema.
+  ([#58](https://github.com/Tinche/uapi/pull/58))
+- Dictionaries are now supported in the OpenAPI schema, rendering to object schemas with `additionalProperties`.
+  ([#58](https://github.com/Tinche/uapi/pull/58))
+
 ## [v23.3.0](https://github.com/tinche/uapi/compare/v23.2.0...v23.3.0) - 2023-12-20
 
 ### Changed

docs/openapi.md

@@ -46,6 +46,10 @@ _uapi_ comes with OpenAPI schema support for the following types:
 - bytes (`type: string, format: binary`)
 - dates (`type: string, format: date`)
 - datetimes (`type: string, format: date-time`)
+- lists (`type: array`)
+- dictionaries (`type: object`, with `additionalProperties`)
+- attrs classes (`type: object`)
+- `typing.Any` (empty schema)
 
 ## Operation Summaries and Descriptions
 

src/uapi/openapi.py

@@ -2,13 +2,14 @@
 from __future__ import annotations
 
 from collections.abc import Callable, Mapping, Sequence
+from contextlib import suppress
 from datetime import date, datetime
 from enum import Enum, unique
 from typing import Any, ClassVar, Literal, TypeAlias
 
 from attrs import Factory, define, field, frozen, has
 from cattrs import override
-from cattrs._compat import get_args, is_generic, is_sequence
+from cattrs._compat import get_args, is_generic, is_mapping, is_sequence
 from cattrs.gen import make_dict_structure_fn, make_dict_unstructure_fn
 from cattrs.preconf.json import make_converter
 
@@ -27,6 +28,11 @@ class Reference:
 
 @frozen
 class Schema:
+    """The generic schema base class.
+
+    Consider using a specialized version (like `IntegerSchema`) instead.
+    """
+
     @unique
     class Type(Enum):
         OBJECT = "object"
@@ -37,7 +43,7 @@ class Type(Enum):
         NULL = "null"
         ARRAY = "array"
 
-    type: Type
+    type: Type | None = None
     properties: dict[str, AnySchema | Reference] | None = None
     format: str | None = None
     additionalProperties: bool | Schema | IntegerSchema | Reference = False
@@ -198,15 +204,37 @@ def get_schema_for_type(
         self, type: Any
     ) -> Reference | Schema | IntegerSchema | ArraySchema:
         # First check inline types.
+        # TODO: Use the rules to build this, instead of duplicating
+        # the logic here.
         if type in self.PYTHON_PRIMITIVES_TO_OPENAPI:
             return self.PYTHON_PRIMITIVES_TO_OPENAPI[type]
+        if type is Any:
+            return Schema()
         if is_sequence(type):
             # Arrays get created inline.
             arg = get_args(type)[0]
             inner = self.get_schema_for_type(arg)
             if not isinstance(inner, ArraySchema):
                 return ArraySchema(inner)
-            raise Exception("Nested arrays are unsupported.")
+            raise Exception("Nested arrays are unsupported")
+
+        mapping = False
+        # TODO: remove this when cattrs 24.1 releases
+        with suppress(TypeError):
+            mapping = is_mapping(type)
+        if mapping:
+            # Dicts also get created inline.
+            args = get_args(type)
+
+            key_type, value_type = args if len(args) == 2 else (Any, Any)
+            # OpenAPI doesn't support anything else.
+            if key_type not in (Any, str):
+                raise Exception(f"Can't handle {type}")
+
+            value_schema = self.get_schema_for_type(value_type)
+            if not isinstance(value_schema, ArraySchema):
+                return Schema(Schema.Type.OBJECT, additionalProperties=value_schema)
+            raise Exception(f"Can't handle {type}")
 
         name = self._name_for(type)
         if name not in self.components and type not in self._build_queue:
@@ -233,6 +261,7 @@ def default_build_rules(cls) -> list[tuple[Predicate, BuildHook]]:
                 cls.PYTHON_PRIMITIVES_TO_OPENAPI.__contains__,
                 lambda t, _: cls.PYTHON_PRIMITIVES_TO_OPENAPI[t],
             ),
+            (lambda t: t is Any, lambda _, __: Schema()),
             (has, build_attrs_schema),
         ]
 
@@ -248,6 +277,8 @@ def _structure_schemas(val, _):
     if "oneOf" in val:
         return converter.structure(val, OneOfSchema)
 
+    if "type" not in val:
+        return Schema()
     type = Schema.Type(val["type"])
     if type is Schema.Type.ARRAY:
         return converter.structure(val, ArraySchema)
@@ -259,6 +290,8 @@ def _structure_schemas(val, _):
 def _structure_schema_or_ref(val, _) -> Schema | IntegerSchema | Reference:
     if "$ref" in val:
         return converter.structure(val, Reference)
+    if "type" not in val:
+        return Schema()
     type = Schema.Type(val["type"])
     if type is Schema.Type.INTEGER:
         return converter.structure(val, IntegerSchema)

tests/apps.py

@@ -156,6 +156,8 @@ async def header_renamed(
     ) -> str:
         return test_header
 
+    # Models and loaders.
+
     @app.put("/custom-loader")
     async def custom_loader(body: CustomReqBody[NestedModel]) -> Ok[str]:
         return Ok(str(body.simple_model.an_int))
@@ -191,6 +193,13 @@ async def generic_model(m: ReqBody[GenericModel[int]]) -> GenericModel[SimpleMod
         """OpenAPI should handle generic models."""
         return GenericModel(SimpleModel(1))
 
+    @app.get("/generic-model-dicts")
+    async def generic_model_dict(
+        m: ReqBody[GenericModel[dict[str, str]]]
+    ) -> GenericModel[dict[str, str]]:
+        """OpenAPI should handle generic models with dicts."""
+        return GenericModel({})
+
     @app.get("/response-model")
     async def response_model() -> ResponseModel:
         return ResponseModel([])
@@ -378,6 +387,8 @@ def non_str_header_no_default(test_header: Header[int]) -> str:
     def header_renamed(test_header: Annotated[str, HeaderSpec("test_header")]) -> str:
         return test_header
 
+    # Models and loaders.
+
     @app.put("/custom-loader")
     def custom_loader(body: CustomReqBody[NestedModel]) -> Ok[str]:
         return Ok(str(body.simple_model.an_int))
@@ -413,6 +424,13 @@ def generic_model(m: ReqBody[GenericModel[int]]) -> GenericModel[SimpleModel]:
         """OpenAPI should handle generic models."""
         return GenericModel(SimpleModel(1))
 
+    @app.get("/generic-model-dicts")
+    def generic_model_dict(
+        m: ReqBody[GenericModel[dict[str, str]]]
+    ) -> GenericModel[dict[str, str]]:
+        """OpenAPI should handle generic models with dicts."""
+        return GenericModel({})
+
     @app.get("/response-model")
     def response_model() -> ResponseModel:
         return ResponseModel([])

tests/openapi/test_openapi_attrs.py

@@ -560,3 +560,41 @@ def handler2(m: ReqBody[Model2]) -> None:
         properties={"b": Schema(Schema.Type.NUMBER, format="double")},
         required=["b"],
     )
+
+
+def test_generic_dicts(app: App) -> None:
+    spec: OpenAPI = app.make_openapi_spec()
+
+    op = spec.paths["/generic-model-dicts"]
+    assert op is not None
+    assert op.get is not None
+
+    assert op.get.parameters == []
+    assert op.get.requestBody == RequestBody(
+        {
+            "application/json": MediaType(
+                Reference("#/components/schemas/GenericModel[dict]")
+            )
+        },
+        required=True,
+    )
+
+    assert op.get.responses["200"]
+    assert op.get.responses["200"].content["application/json"].schema == Reference(
+        "#/components/schemas/GenericModel[dict]"
+    )
+
+    assert spec.components.schemas["GenericModel[dict]"] == Schema(
+        Schema.Type.OBJECT,
+        properties={
+            "a": Schema(
+                Schema.Type.OBJECT, additionalProperties=Schema(Schema.Type.STRING)
+            ),
+            "b": ArraySchema(
+                Schema(
+                    Schema.Type.OBJECT, additionalProperties=Schema(Schema.Type.STRING)
+                )
+            ),
+        },
+        required=["a"],
+    )