init() — fastapi Function Reference

Architecture documentation for the __init__() function in params.py from the fastapi codebase.

Function python FastAPI Routing

Entity Profile

FastAPI→ Routing→ __init__() — fastapi Function Reference

Dependency Diagram

graph TD
  a4d2cfe1_a375_1234_ebb0_dc2d0318e19f["__init__()"]
  a15334a5_304f_0e4c_dce0_12ffde49a6b7["Param"]
  a4d2cfe1_a375_1234_ebb0_dc2d0318e19f -->|defined in| a15334a5_304f_0e4c_dce0_12ffde49a6b7
  style a4d2cfe1_a375_1234_ebb0_dc2d0318e19f fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

fastapi/params.py lines 30–132

    def __init__(
        self,
        default: Any = Undefined,
        *,
        default_factory: Union[Callable[[], Any], None] = _Unset,
        annotation: Optional[Any] = None,
        alias: Optional[str] = None,
        alias_priority: Union[int, None] = _Unset,
        validation_alias: Union[str, AliasPath, AliasChoices, None] = None,
        serialization_alias: Union[str, None] = None,
        title: Optional[str] = None,
        description: Optional[str] = None,
        gt: Optional[float] = None,
        ge: Optional[float] = None,
        lt: Optional[float] = None,
        le: Optional[float] = None,
        min_length: Optional[int] = None,
        max_length: Optional[int] = None,
        pattern: Optional[str] = None,
        regex: Annotated[
            Optional[str],
            deprecated(
                "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
            ),
        ] = None,
        discriminator: Union[str, None] = None,
        strict: Union[bool, None] = _Unset,
        multiple_of: Union[float, None] = _Unset,
        allow_inf_nan: Union[bool, None] = _Unset,
        max_digits: Union[int, None] = _Unset,
        decimal_places: Union[int, None] = _Unset,
        examples: Optional[list[Any]] = 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: Optional[dict[str, Example]] = None,
        deprecated: Union[deprecated, str, bool, None] = None,
        include_in_schema: bool = True,
        json_schema_extra: Union[dict[str, Any], None] = None,
        **extra: Any,
    ):
        if example is not _Unset:
            warnings.warn(
                "`example` has been deprecated, please use `examples` instead",
                category=FastAPIDeprecationWarning,
                stacklevel=4,
            )
        self.example = example
        self.include_in_schema = include_in_schema
        self.openapi_examples = openapi_examples
        kwargs = dict(
            default=default,
            default_factory=default_factory,
            alias=alias,
            title=title,
            description=description,
            gt=gt,
            ge=ge,
            lt=lt,
            le=le,
            min_length=min_length,
            max_length=max_length,
            discriminator=discriminator,
            multiple_of=multiple_of,
            allow_inf_nan=allow_inf_nan,
            max_digits=max_digits,
            decimal_places=decimal_places,
            **extra,
        )
        if examples is not None:
            kwargs["examples"] = examples
        if regex is not None:
            warnings.warn(
                "`regex` has been deprecated, please use `pattern` instead",
                category=FastAPIDeprecationWarning,
                stacklevel=4,
            )