请求参数

这里是请求参数的参考信息。

这些是特殊函数，你可以把它们放在 *path 操作函数 * 参数或带有注释的依赖函数中，以便从请求中获取数据。

其中包括：

• Query()
• Path()
• Body()
• Cookie()
• Header()
• Form()
• File()

您可以直接从 fastapi 中导入它们：

from fastapi import Body, Cookie, File, Form, Header, Path, Query

fastapi.Query

Query(
    default=Undefined,
    *,
    default_factory=_Unset,
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Query(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.Query(
        default=default,
        default_factory=default_factory,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.Path

Path(
    default=...,
    *,
    default_factory=_Unset,
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

Declare a path parameter for a path operation.

Read more about it in the FastAPI docs for Path Parameters and Numeric Validations.

from typing import Annotated

from fastapi import FastAPI, Path

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    item_id: Annotated[int, Path(title="The ID of the item to get")],
):
    return {"item_id": item_id}

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Any DEFAULT: ...
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Path(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = ...,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    """
    Declare a path parameter for a *path operation*.

    Read more about it in the
    [FastAPI docs for Path Parameters and Numeric Validations](https://fastapi.tiangolo.com/tutorial/path-params-numeric-validations/).

    ```python
    from typing import Annotated

    from fastapi import FastAPI, Path

    app = FastAPI()


    @app.get("/items/{item_id}")
    async def read_items(
        item_id: Annotated[int, Path(title="The ID of the item to get")],
    ):
        return {"item_id": item_id}
    ```
    """
    return params.Path(
        default=default,
        default_factory=default_factory,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.Body

Body(
    default=Undefined,
    *,
    default_factory=_Unset,
    embed=False,
    media_type="application/json",
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
embed	When embed is True, the parameter will be expected in a JSON body as a key instead of being the JSON body itself. This happens automatically when more than one Body parameter is declared. Read more about it in the FastAPI docs for Body - Multiple Parameters. TYPE: bool DEFAULT: False
media_type	The media type of this parameter field. Changing it would affect the generated OpenAPI, but currently it doesn't affect the parsing of the data. TYPE: str DEFAULT: 'application/json'
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Body(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    embed: Annotated[
        bool,
        Doc(
            """
            When `embed` is `True`, the parameter will be expected in a JSON body as a
            key instead of being the JSON body itself.

            This happens automatically when more than one `Body` parameter is declared.

            Read more about it in the
            [FastAPI docs for Body - Multiple Parameters](https://fastapi.tiangolo.com/tutorial/body-multiple-params/#embed-a-single-body-parameter).
            """
        ),
    ] = False,
    media_type: Annotated[
        str,
        Doc(
            """
            The media type of this parameter field. Changing it would affect the
            generated OpenAPI, but currently it doesn't affect the parsing of the data.
            """
        ),
    ] = "application/json",
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.Body(
        default=default,
        default_factory=default_factory,
        embed=embed,
        media_type=media_type,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.Cookie

Cookie(
    default=Undefined,
    *,
    default_factory=_Unset,
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Cookie(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.Cookie(
        default=default,
        default_factory=default_factory,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.Header

Header(
    default=Undefined,
    *,
    default_factory=_Unset,
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    convert_underscores=True,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
convert_underscores	Automatically convert underscores to hyphens in the parameter field name. Read more about it in the FastAPI docs for Header Parameters TYPE: bool DEFAULT: True
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Header(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    convert_underscores: Annotated[
        bool,
        Doc(
            """
            Automatically convert underscores to hyphens in the parameter field name.

            Read more about it in the
            [FastAPI docs for Header Parameters](https://fastapi.tiangolo.com/tutorial/header-params/#automatic-conversion)
            """
        ),
    ] = True,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.Header(
        default=default,
        default_factory=default_factory,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        convert_underscores=convert_underscores,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.Form

Form(
    default=Undefined,
    *,
    default_factory=_Unset,
    media_type="application/x-www-form-urlencoded",
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
media_type	The media type of this parameter field. Changing it would affect the generated OpenAPI, but currently it doesn't affect the parsing of the data. TYPE: str DEFAULT: 'application/x-www-form-urlencoded'
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def Form(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    media_type: Annotated[
        str,
        Doc(
            """
            The media type of this parameter field. Changing it would affect the
            generated OpenAPI, but currently it doesn't affect the parsing of the data.
            """
        ),
    ] = "application/x-www-form-urlencoded",
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.Form(
        default=default,
        default_factory=default_factory,
        media_type=media_type,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )

fastapi.File

File(
    default=Undefined,
    *,
    default_factory=_Unset,
    media_type="multipart/form-data",
    alias=None,
    alias_priority=_Unset,
    validation_alias=None,
    serialization_alias=None,
    title=None,
    description=None,
    gt=None,
    ge=None,
    lt=None,
    le=None,
    min_length=None,
    max_length=None,
    pattern=None,
    regex=None,
    discriminator=None,
    strict=_Unset,
    multiple_of=_Unset,
    allow_inf_nan=_Unset,
    max_digits=_Unset,
    decimal_places=_Unset,
    examples=None,
    example=_Unset,
    openapi_examples=None,
    deprecated=None,
    include_in_schema=True,
    json_schema_extra=None,
    **extra
)

PARAMETER	DESCRIPTION
default	Default value if the parameter field is not set. TYPE: Any DEFAULT: Undefined
default_factory	A callable to generate the default value. This doesn't affect Path parameters as the value is always required. The parameter is available only for compatibility. TYPE: Union[Callable[[], Any], None] DEFAULT: _Unset
media_type	The media type of this parameter field. Changing it would affect the generated OpenAPI, but currently it doesn't affect the parsing of the data. TYPE: str DEFAULT: 'multipart/form-data'
alias	An alternative name for the parameter field. This will be used to extract the data and for the generated OpenAPI. It is particularly useful when you can't use the name you want because it is a Python reserved keyword or similar. TYPE: Optional[str] DEFAULT: None
alias_priority	Priority of the alias. This affects whether an alias generator is used. TYPE: Union[int, None] DEFAULT: _Unset
validation_alias	'Whitelist' validation step. The parameter field will be the single one allowed by the alias or set of aliases defined. TYPE: Union[str, None] DEFAULT: None
serialization_alias	'Blacklist' validation step. The vanilla parameter field will be the single one of the alias' or set of aliases' fields and all the other fields will be ignored at serialization time. TYPE: Union[str, None] DEFAULT: None
title	Human-readable title. TYPE: Optional[str] DEFAULT: None
description	Human-readable description. TYPE: Optional[str] DEFAULT: None
gt	Greater than. If set, value must be greater than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
ge	Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
lt	Less than. If set, value must be less than this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
le	Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. TYPE: Optional[float] DEFAULT: None
min_length	Minimum length for strings. TYPE: Optional[int] DEFAULT: None
max_length	Maximum length for strings. TYPE: Optional[int] DEFAULT: None
pattern	RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
regex	Deprecated in FastAPI 0.100.0 and Pydantic v2, use pattern instead. RegEx pattern for strings. TYPE: Optional[str] DEFAULT: None
discriminator	Parameter field name for discriminating the type in a tagged union. TYPE: Union[str, None] DEFAULT: None
strict	If True, strict validation is applied to the field. TYPE: Union[bool, None] DEFAULT: _Unset
multiple_of	Value must be a multiple of this. Only applicable to numbers. TYPE: Union[float, None] DEFAULT: _Unset
allow_inf_nan	Allow inf, -inf, nan. Only applicable to numbers. TYPE: Union[bool, None] DEFAULT: _Unset
max_digits	Maximum number of allow digits for strings. TYPE: Union[int, None] DEFAULT: _Unset
decimal_places	Maximum number of decimal places allowed for numbers. TYPE: Union[int, None] DEFAULT: _Unset
examples	Example values for this field. TYPE: Optional[List[Any]] DEFAULT: None
example	Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, although still supported. Use examples instead. TYPE: Optional[Any] DEFAULT: _Unset
openapi_examples	OpenAPI-specific examples. It will be added to the generated OpenAPI (e.g. visible at /docs). Swagger UI (that provides the /docs interface) has better support for the OpenAPI-specific examples than the JSON Schema examples, that's the main use case for this. Read more about it in the FastAPI docs for Declare Request Example Data. TYPE: Optional[Dict[str, Example]] DEFAULT: None
deprecated	Mark this parameter field as deprecated. It will affect the generated OpenAPI (e.g. visible at /docs). TYPE: Union[deprecated, str, bool, None] DEFAULT: None
include_in_schema	To include (or not) this parameter field in the generated OpenAPI. You probably don't need it, but it's available. This affects the generated OpenAPI (e.g. visible at /docs). TYPE: bool DEFAULT: True
json_schema_extra	Any additional JSON schema data. TYPE: Union[Dict[str, Any], None] DEFAULT: None
**extra	The extra kwargs is deprecated. Use json_schema_extra instead. Include extra fields used by the JSON Schema. TYPE: Any DEFAULT: {}

Source code in fastapi/param_functions.py

def File(  # noqa: N802
    default: Annotated[
        Any,
        Doc(
            """
            Default value if the parameter field is not set.
            """
        ),
    ] = Undefined,
    *,
    default_factory: Annotated[
        Union[Callable[[], Any], None],
        Doc(
            """
            A callable to generate the default value.

            This doesn't affect `Path` parameters as the value is always required.
            The parameter is available only for compatibility.
            """
        ),
    ] = _Unset,
    media_type: Annotated[
        str,
        Doc(
            """
            The media type of this parameter field. Changing it would affect the
            generated OpenAPI, but currently it doesn't affect the parsing of the data.
            """
        ),
    ] = "multipart/form-data",
    alias: Annotated[
        Optional[str],
        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """
            Priority of the alias. This affects whether an alias generator is used.
            """
        ),
    ] = _Unset,
    # TODO: update when deprecating Pydantic v1, import these types
    # validation_alias: str | AliasPath | AliasChoices | None
    validation_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the
            single one of the alias' or set of aliases' fields and all the other
            fields will be ignored at serialization time.
            """
        ),
    ] = None,
    title: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable title.
            """
        ),
    ] = None,
    description: Annotated[
        Optional[str],
        Doc(
            """
            Human-readable description.
            """
        ),
    ] = None,
    gt: Annotated[
        Optional[float],
        Doc(
            """
            Greater than. If set, value must be greater than this. Only applicable to
            numbers.
            """
        ),
    ] = None,
    ge: Annotated[
        Optional[float],
        Doc(
            """
            Greater than or equal. If set, value must be greater than or equal to
            this. Only applicable to numbers.
            """
        ),
    ] = None,
    lt: Annotated[
        Optional[float],
        Doc(
            """
            Less than. If set, value must be less than this. Only applicable to numbers.
            """
        ),
    ] = None,
    le: Annotated[
        Optional[float],
        Doc(
            """
            Less than or equal. If set, value must be less than or equal to this.
            Only applicable to numbers.
            """
        ),
    ] = None,
    min_length: Annotated[
        Optional[int],
        Doc(
            """
            Minimum length for strings.
            """
        ),
    ] = None,
    max_length: Annotated[
        Optional[int],
        Doc(
            """
            Maximum length for strings.
            """
        ),
    ] = None,
    pattern: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
    ] = None,
    regex: Annotated[
        Optional[str],
        Doc(
            """
            RegEx pattern for strings.
            """
        ),
        deprecated(
            "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
        ),
    ] = None,
    discriminator: Annotated[
        Union[str, None],
        Doc(
            """
            Parameter field name for discriminating the type in a tagged union.
            """
        ),
    ] = None,
    strict: Annotated[
        Union[bool, None],
        Doc(
            """
            If `True`, strict validation is applied to the field.
            """
        ),
    ] = _Unset,
    multiple_of: Annotated[
        Union[float, None],
        Doc(
            """
            Value must be a multiple of this. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    allow_inf_nan: Annotated[
        Union[bool, None],
        Doc(
            """
            Allow `inf`, `-inf`, `nan`. Only applicable to numbers.
            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of decimal places allowed for numbers.
            """
        ),
    ] = _Unset,
    examples: Annotated[
        Optional[List[Any]],
        Doc(
            """
            Example values for this field.
            """
        ),
    ] = None,
    example: Annotated[
        Optional[Any],
        deprecated(
            "Deprecated in OpenAPI 3.1.0 that now uses JSON Schema 2020-12, "
            "although still supported. Use examples instead."
        ),
    ] = _Unset,
    openapi_examples: Annotated[
        Optional[Dict[str, Example]],
        Doc(
            """
            OpenAPI-specific examples.

            It will be added to the generated OpenAPI (e.g. visible at `/docs`).

            Swagger UI (that provides the `/docs` interface) has better support for the
            OpenAPI-specific examples than the JSON Schema `examples`, that's the main
            use case for this.

            Read more about it in the
            [FastAPI docs for Declare Request Example Data](https://fastapi.tiangolo.com/tutorial/schema-extra-example/#using-the-openapi_examples-parameter).
            """
        ),
    ] = None,
    deprecated: Annotated[
        Union[deprecated, str, bool, None],
        Doc(
            """
            Mark this parameter field as deprecated.

            It will affect the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = None,
    include_in_schema: Annotated[
        bool,
        Doc(
            """
            To include (or not) this parameter field in the generated OpenAPI.
            You probably don't need it, but it's available.

            This affects the generated OpenAPI (e.g. visible at `/docs`).
            """
        ),
    ] = True,
    json_schema_extra: Annotated[
        Union[Dict[str, Any], None],
        Doc(
            """
            Any additional JSON schema data.
            """
        ),
    ] = None,
    **extra: Annotated[
        Any,
        Doc(
            """
            Include extra fields used by the JSON Schema.
            """
        ),
        deprecated(
            """
            The `extra` kwargs is deprecated. Use `json_schema_extra` instead.
            """
        ),
    ],
) -> Any:
    return params.File(
        default=default,
        default_factory=default_factory,
        media_type=media_type,
        alias=alias,
        alias_priority=alias_priority,
        validation_alias=validation_alias,
        serialization_alias=serialization_alias,
        title=title,
        description=description,
        gt=gt,
        ge=ge,
        lt=lt,
        le=le,
        min_length=min_length,
        max_length=max_length,
        pattern=pattern,
        regex=regex,
        discriminator=discriminator,
        strict=strict,
        multiple_of=multiple_of,
        allow_inf_nan=allow_inf_nan,
        max_digits=max_digits,
        decimal_places=decimal_places,
        example=example,
        examples=examples,
        openapi_examples=openapi_examples,
        deprecated=deprecated,
        include_in_schema=include_in_schema,
        json_schema_extra=json_schema_extra,
        **extra,
    )