tiangolo.fastapi/tests/test_root_model.py

from typing import Any, Dict, List, Type, Union

import pytest
from dirty_equals import IsDict
from fastapi import Body, FastAPI, Path, Query
from fastapi._compat import PYDANTIC_V2
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

if PYDANTIC_V2:
    from pydantic import ConfigDict, Field, RootModel, field_validator, model_serializer

    Basic = RootModel[int]

    class FieldWrap(RootModel[str]):
        model_config = ConfigDict(
            json_schema_extra={"description": "parameter starts with bar_"}
        )
        root: str = Field(pattern=r"^bar_.*$")

    class CustomParsed(RootModel[str]):
        model_config = ConfigDict(
            json_schema_extra={"description": "parameter starts with foo_"}
        )

        @field_validator("root")
        @classmethod
        def validator(cls, v: str) -> str:
            if not v.startswith("foo_"):
                raise ValueError("must start with foo_")
            return v

        @model_serializer
        def serialize(self):
            return (
                self.root
                if self.root.endswith("_serialized")
                else f"{self.root}_serialized"
            )

        def parse(self):
            return self.root[len("foo_") :]  # removeprefix

    class DictWrap(RootModel[Dict[str, int]]):
        pass
else:
    from pydantic import Field, validator

    class Basic(BaseModel):
        __root__: int

    class FieldWrap(BaseModel):
        class Config:
            schema_extra = {"description": "parameter starts with bar_"}

        __root__: str = Field(regex=r"^bar_.*$")

    class CustomParsed(BaseModel):
        class Config:
            schema_extra = {"description": "parameter starts with foo_"}

        __root__: str

        @validator("__root__")
        @classmethod
        def validator(cls, v: str) -> str:
            if not v.startswith("foo_"):
                raise ValueError("must start with foo_")
            return v

        def dict(self, **kwargs: Any) -> Dict[str, Any]:
            return {
                "__root__": self.__root__
                if self.__root__.endswith("_serialized")
                else f"{self.__root__}_serialized"
            }

        def parse(self):
            return self.__root__[len("foo_") :]  # removeprefix

    class DictWrap(BaseModel):
        __root__: Dict[str, int]


@app.get("/query/basic")
def query_basic(q: Basic = Query()):
    return {"q": q}


@app.get("/query/fieldwrap")
def query_fieldwrap(q: FieldWrap = Query()):
    return {"q": q}


@app.get("/query/customparsed")
def query_customparsed(q: CustomParsed = Query()):
    return {"q": q.parse()}


@app.get("/path/basic/{p}")
def path_basic(p: Basic = Path()):
    return {"p": p}


@app.get("/path/fieldwrap/{p}")
def path_fieldwrap(p: FieldWrap = Path()):
    return {"p": p}


@app.get("/path/customparsed/{p}")
def path_customparsed(p: CustomParsed = Path()):
    return {"p": p.parse()}


@app.post("/body/basic")
def body_basic(b: Basic = Body()):
    return {"b": b}


@app.post("/body/fieldwrap")
def body_fieldwrap(b: FieldWrap = Body()):
    return {"b": b}


@app.post("/body/customparsed")
def body_customparsed(b: CustomParsed = Body()):
    return {"b": b.parse()}


@app.post("/body_default/basic")
def body_default_basic(b: Basic):
    return {"b": b}


@app.post("/body_default/fieldwrap")
def body_default_fieldwrap(b: FieldWrap):
    return {"b": b}


@app.post("/body_default/customparsed")
def body_default_customparsed(b: CustomParsed):
    return {"b": b.parse()}


@app.get("/echo/basic")
def echo_basic(q: Basic = Query()) -> Basic:
    return q


@app.get("/echo/fieldwrap")
def echo_fieldwrap(q: FieldWrap = Query()) -> FieldWrap:
    return q


@app.get("/echo/customparsed")
def echo_customparsed(q: CustomParsed = Query()) -> CustomParsed:
    return q


@app.post("/echo/dictwrap")
def echo_dictwrap(b: DictWrap) -> DictWrap:
    return b.model_dump() if PYDANTIC_V2 else b.dict()["__root__"]


client = TestClient(app)


@pytest.mark.parametrize(
    "url, response_json, request_body",
    [
        ("/query/basic?q=42", {"q": 42}, None),
        ("/query/fieldwrap?q=bar_baz", {"q": "bar_baz"}, None),
        ("/query/customparsed?q=foo_bar", {"q": "bar"}, None),
        ("/path/basic/42", {"p": 42}, None),
        ("/path/fieldwrap/bar_baz", {"p": "bar_baz"}, None),
        ("/path/customparsed/foo_bar", {"p": "bar"}, None),
        ("/body/basic", {"b": 42}, "42"),
        ("/body/fieldwrap", {"b": "bar_baz"}, "bar_baz"),
        ("/body/customparsed", {"b": "bar"}, "foo_bar"),
        ("/body_default/basic", {"b": 42}, "42"),
        ("/body_default/fieldwrap", {"b": "bar_baz"}, "bar_baz"),
        ("/body_default/customparsed", {"b": "bar"}, "foo_bar"),
        ("/echo/basic?q=42", 42, None),
        ("/echo/fieldwrap?q=bar_baz", "bar_baz", None),
        ("/echo/customparsed?q=foo_bar", "foo_bar_serialized", None),
        ("/echo/dictwrap", {"test": 1}, {"test": 1}),
    ],
)
def test_root_model_200(url: str, response_json: Any, request_body: Any):
    response = client.post(url, json=request_body) if request_body else client.get(url)
    assert response.status_code == 200, response.text
    assert response.json() == response_json


def test_root_model_union():
    if PYDANTIC_V2:
        from pydantic import RootModel

        RootModelInt = RootModel[int]
        RootModelStr = RootModel[str]
    else:

        class RootModelInt(BaseModel):
            __root__: int

        class RootModelStr(BaseModel):
            __root__: str

    app2 = FastAPI()

    @app2.post("/union")
    def union_handler(b: Union[RootModelInt, RootModelStr]):
        return {"b": b}

    client2 = TestClient(app2)
    for body in [42, "foo"]:
        response = client2.post("/union", json=body)
        assert response.status_code == 200, response.text
        assert response.json() == {"b": body}

    response = client2.post("/union", json=["bad_list"])
    assert response.status_code == 422, response.text
    if PYDANTIC_V2:
        assert {detail["msg"] for detail in response.json()["detail"]} == {
            "Input should be a valid integer",
            "Input should be a valid string",
        }
    else:
        assert {detail["msg"] for detail in response.json()["detail"]} == {
            "value is not a valid integer",
            "str type expected",
        }


@pytest.mark.parametrize(
    "url, error_path, request_body",
    [
        ("/query/basic?q=my_bad_not_int", ["query", "q"], None),
        ("/path/basic/my_bad_not_int", ["path", "p"], None),
        ("/body/basic", ["body"], "my_bad_not_int"),
        ("/body_default/basic", ["body"], "my_bad_not_int"),
    ],
)
def test_root_model_basic_422(url: str, error_path: List[str], request_body: Any):
    response = client.post(url, json=request_body) if request_body else client.get(url)
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "int_parsing",
                    "loc": error_path,
                    "msg": "Input should be a valid integer, unable to parse string as an integer",
                    "input": "my_bad_not_int",
                }
            ]
        }
    ) | IsDict(
        # TODO: remove when deprecating Pydantic v1
        {
            "detail": [
                {
                    "loc": [*error_path, "__root__"],
                    "msg": "value is not a valid integer",
                    "type": "type_error.integer",
                }
            ]
        }
    )


@pytest.mark.parametrize(
    "url, error_path, request_body",
    [
        ("/query/fieldwrap?q=my_bad_prefix_val", ["query", "q"], None),
        ("/path/fieldwrap/my_bad_prefix_val", ["path", "p"], None),
        ("/body/fieldwrap", ["body"], "my_bad_prefix_val"),
        ("/body_default/fieldwrap", ["body"], "my_bad_prefix_val"),
    ],
)
def test_root_model_fieldwrap_422(url: str, error_path: List[str], request_body: Any):
    response = client.post(url, json=request_body) if request_body else client.get(url)
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "string_pattern_mismatch",
                    "loc": error_path,
                    "msg": "String should match pattern '^bar_.*$'",
                    "input": "my_bad_prefix_val",
                    "ctx": {"pattern": "^bar_.*$"},
                }
            ]
        }
    ) | IsDict(
        # TODO: remove when deprecating Pydantic v1
        {
            "detail": [
                {
                    "loc": [*error_path, "__root__"],
                    "msg": 'string does not match regex "^bar_.*$"',
                    "type": "value_error.str.regex",
                    "ctx": {"pattern": "^bar_.*$"},
                }
            ]
        }
    )


@pytest.mark.parametrize(
    "url, error_path, request_body",
    [
        ("/query/customparsed?q=my_bad_prefix_val", ["query", "q"], None),
        ("/path/customparsed/my_bad_prefix_val", ["path", "p"], None),
        ("/body/customparsed", ["body"], "my_bad_prefix_val"),
        ("/body_default/customparsed", ["body"], "my_bad_prefix_val"),
    ],
)
def test_root_model_customparsed_422(
    url: str, error_path: List[str], request_body: Any
):
    response = client.post(url, json=request_body) if request_body else client.get(url)
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "value_error",
                    "loc": error_path,
                    "msg": "Value error, must start with foo_",
                    "input": "my_bad_prefix_val",
                    "ctx": {"error": {}},
                }
            ]
        }
    ) | IsDict(
        # TODO: remove when deprecating Pydantic v1
        {
            "detail": [
                {
                    "loc": [*error_path, "__root__"],
                    "msg": "must start with foo_",
                    "type": "value_error",
                }
            ]
        }
    )


def test_root_model_dictwrap_422():
    response = client.post("/echo/dictwrap", json={"test": "fail_not_int"})
    assert response.status_code == 422, response.text
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "int_parsing",
                    "loc": ["body", "test"],
                    "msg": "Input should be a valid integer, unable to parse string as an integer",
                    "input": "fail_not_int",
                }
            ]
        }
    ) | IsDict(
        # TODO: remove when deprecating Pydantic v1
        {
            "detail": [
                {
                    "loc": ["body", "__root__", "test"],
                    "msg": "value is not a valid integer",
                    "type": "type_error.integer",
                }
            ]
        }
    )


@pytest.mark.parametrize(
    "model, path_name, expected_model_schema",
    [
        (Basic, "basic", {"type": "integer"}),
        (
            FieldWrap,
            "fieldwrap",
            {
                "type": "string",
                "pattern": "^bar_.*$",
                "description": "parameter starts with bar_",
            },
        ),
        (
            CustomParsed,
            "customparsed",
            {
                "type": "string",
                "description": "parameter starts with foo_",
            },
        ),
    ],
)
def test_openapi_schema(
    model: Type, path_name: str, expected_model_schema: Dict[str, Any]
):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

    paths = response.json()["paths"]
    ref_name = model.__name__.replace("[", "_").replace("]", "_")
    schema_ref = {"schema": {"$ref": f"#/components/schemas/{ref_name}"}}

    assert paths[f"/query/{path_name}"]["get"]["parameters"] == [
        {"in": "query", "name": "q", "required": True, **schema_ref}
    ]
    assert paths[f"/path/{path_name}/{{p}}"]["get"]["parameters"] == [
        {"in": "path", "name": "p", "required": True, **schema_ref}
    ]
    assert paths[f"/body/{path_name}"]["post"]["requestBody"] == {
        "content": {"application/json": schema_ref},
        "required": True,
    }
    assert paths[f"/body_default/{path_name}"]["post"]["requestBody"] == {
        "content": {"application/json": schema_ref},
        "required": True,
    }
    assert paths[f"/echo/{path_name}"]["get"]["responses"]["200"] == {
        "content": {"application/json": schema_ref},
        "description": "Successful Response",
    }

    model_schema = response.json()["components"]["schemas"][ref_name]
    model_schema.pop("title")
    assert model_schema == expected_model_schema


def test_openapi_schema_dictwrap():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

    operation = response.json()["paths"]["/echo/dictwrap"]["post"]
    ref = {"schema": {"$ref": "#/components/schemas/DictWrap"}}
    assert operation["requestBody"] == {
        "content": {"application/json": ref},
        "required": True,
    }
    assert operation["responses"]["200"] == {
        "content": {"application/json": ref},
        "description": "Successful Response",
    }
    assert response.json()["components"]["schemas"]["DictWrap"] == {
        "title": "DictWrap",
        "type": "object",
        "additionalProperties": {"type": "integer"},
    }