UploadFile Class — fastapi Architecture

Architecture documentation for the UploadFile class in datastructures.py from the fastapi codebase.

Class python FastAPI

Entity Profile

FastAPI→ UploadFile Class — fastapi Architecture

Dependency Diagram

graph TD
  e7f7f9d0_3e61_b391_e95f_2212c3046b08["UploadFile"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08["UploadFile"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|extends| e7f7f9d0_3e61_b391_e95f_2212c3046b08
  dc4a1804_f7b4_848b_3280_30523680d7b9["datastructures.py"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|defined in| dc4a1804_f7b4_848b_3280_30523680d7b9
  bd22fc1b_4f68_64ff_378d_a081f71b63c3["write()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| bd22fc1b_4f68_64ff_378d_a081f71b63c3
  1d8546f2_90ed_9120_dbc5_d713e7cf8085["read()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| 1d8546f2_90ed_9120_dbc5_d713e7cf8085
  c591c04f_f53b_0c31_4022_096ff9bf737b["seek()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| c591c04f_f53b_0c31_4022_096ff9bf737b
  76af83fd_46f7_5935_efc3_87a0773b471d["close()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| 76af83fd_46f7_5935_efc3_87a0773b471d
  4a2d48d6_8997_af53_93c8_8a157af0c15a["_validate()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| 4a2d48d6_8997_af53_93c8_8a157af0c15a
  9349e819_1a2c_f5b3_a5de_bac4bf977f83["__get_pydantic_json_schema__()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| 9349e819_1a2c_f5b3_a5de_bac4bf977f83
  9be5e1e8_1a6a_82d4_62d1_cb95697c7fef["__get_pydantic_core_schema__()"]
  e7f7f9d0_3e61_b391_e95f_2212c3046b08 -->|method| 9be5e1e8_1a6a_82d4_62d1_cb95697c7fef

Relationship Graph

Source Code

fastapi/datastructures.py lines 23–152

class UploadFile(StarletteUploadFile):
    """
    A file uploaded in a request.

    Define it as a *path operation function* (or dependency) parameter.

    If you are using a regular `def` function, you can use the `upload_file.file`
    attribute to access the raw standard Python file (blocking, not async), useful and
    needed for non-async code.

    Read more about it in the
    [FastAPI docs for Request Files](https://fastapi.tiangolo.com/tutorial/request-files/).

    ## Example

    ```python
    from typing import Annotated

    from fastapi import FastAPI, File, UploadFile

    app = FastAPI()


    @app.post("/files/")
    async def create_file(file: Annotated[bytes, File()]):
        return {"file_size": len(file)}


    @app.post("/uploadfile/")
    async def create_upload_file(file: UploadFile):
        return {"filename": file.filename}
    ```
    """

    file: Annotated[
        BinaryIO,
        Doc("The standard Python file object (non-async)."),
    ]
    filename: Annotated[Optional[str], Doc("The original file name.")]
    size: Annotated[Optional[int], Doc("The size of the file in bytes.")]
    headers: Annotated[Headers, Doc("The headers of the request.")]
    content_type: Annotated[
        Optional[str], Doc("The content type of the request, from the headers.")
    ]

    async def write(
        self,
        data: Annotated[
            bytes,
            Doc(
                """
                The bytes to write to the file.
                """
            ),
        ],
    ) -> None:
        """
        Write some bytes to the file.

        You normally wouldn't use this from a file you read in a request.

        To be awaitable, compatible with async, this is run in threadpool.
        """
        return await super().write(data)

    async def read(
        self,
        size: Annotated[
            int,
            Doc(
                """
                The number of bytes to read from the file.
                """
            ),
        ] = -1,
    ) -> bytes:
        """
        Read some bytes from the file.

        To be awaitable, compatible with async, this is run in threadpool.
        """