# `UploadFile` class

You can define *path operation function* parameters to be of the type `UploadFile` to receive files from the request.

You can import it directly from `fastapi`:

```python
from fastapi import UploadFile
```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type
            - read

          <description>
            Toolchain identification information, which will be matched against project requirements.
            &lt;p>Actual content structure is completely open: each toolchain type will define its own format and
            semantics.
            &lt;p>This is generally a properties format: {@code &lt;name&gt;value&lt;/name&gt;} with predefined
            properties names.
          </description>

from typing import Any, Dict, List, Optional, Sequence, Set, Tuple, Type, Union, cast

from fastapi import routing
from fastapi._compat import (
    GenerateJsonSchema,
    JsonSchemaValue,
    ModelField,
    Undefined,
    get_compat_model_name_map,
    get_definitions,
    get_schema_from_model_field,
    lenient_issubclass,
)
from fastapi.datastructures import DefaultPlaceholder
from fastapi.dependencies.models import Dependant

      max*)
        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
        # shellcheck disable=SC2039,SC3045
        MAX_FD=$( ulimit -H -n ) ||
            warn "Could not query maximum file descriptor limit"
    esac
    case $MAX_FD in  #(
      '' | soft) :;; #(
      *)
        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.

# Define this here and not in the main mkdocs.yml file because that one is auto
# updated and written, and the script would remove the env var
INHERIT: !ENV [INSIDERS_FILE, '../en/mkdocs.no-insiders.yml']
markdown_extensions:
  pymdownx.highlight:

Se você não se importa com qualquer um desses termos e só precisa adicionar segurança com autenticação baseada em usuário e senha _agora_, pule para os próximos capítulos.

## OAuth2

OAuth2 é uma especificação que define várias formas para lidar com autenticação e autorização.

Ela é bastante extensiva na especificação e cobre casos de uso muito complexos.

Ela inclui uma forma para autenticação usando “third party”/aplicações de terceiros.

# Request Files

You can define files to be uploaded by the client using `File`.

/// info

To receive uploaded files, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

      max*)
        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
        # shellcheck disable=SC2039,SC3045
        MAX_FD=$( ulimit -H -n ) ||
            warn "Could not query maximum file descriptor limit"
    esac
    case $MAX_FD in  #(
      '' | soft) :;; #(
      *)
        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.

# Background Tasks

You can define background tasks to be run *after* returning a response.

This is useful for operations that need to happen after a request, but that the client doesn't really have to be waiting for the operation to complete before receiving the response.

This includes, for example:

* Email notifications sent after performing an action:

func TestOpenNetns(t *testing.T) {
	ns, err := OpenNetns("/proc/self/ns/net")
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	// the inode for netns is proc dynamic, so it needs to be higher than
	// #define PROC_DYNAMIC_FIRST 0xF0000000U

	if ns.Inode() < 0xF0000000 {
		t.Fatalf("unexpected inode: %v", ns.Inode())
	}
	defer ns.Close()