executor.shutdown();

            // Some requests should be rejected due to backpressure
            assertTrue(rejectedCount.get() > 0, "Some requests should be rejected by backpressure");
            assertTrue(successCount.get() > 0, "Some requests should succeed");
            assertEquals(5, rejectedCount.get() + successCount.get(), "Total should be 5");

   * documentation for {@link Collection}:
   *
   * <blockquote>
   *
   * "Some collection implementations have restrictions on the elements that they may contain. For
   * example, some implementations prohibit null elements, and some have restrictions on the types
   * of their elements."
   *
   * </blockquote>
   */
  RESTRICTS_ELEMENTS,

  /**

extend-exclude = [".git/", "docs/", "CREDITS", "go.mod", "go.sum"]
ignore-hidden = false

[default]
extend-ignore-re = [
    "Patrick Collison",
    "Copyright 2014 Unknwon",
    "[0-9A-Za-z/+=]{64}",
    "ZXJuZXQxDjAMBgNVBA-some-junk-Q4wDAYDVQQLEwVNaW5pbzEOMAwGA1UEAxMF",
    "eyJmb28iOiJiYXIifQ",
    "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.*",
    "MIIDBTCCAe2gAwIBAgIQWHw7h.*",
    'http\.Header\{"X-Amz-Server-Side-Encryptio":',

{* ../../docs_src/cookie_param_models/tutorial002_an_py39.py hl[10] *}

If a client tries to send some **extra cookies**, they will receive an **error** response.

Poor cookie banners with all their effort to get your consent for the <abbr title="This is another joke. Don't pay attention to me. Have some coffee for your cookie. ☕">API to reject it</abbr>. 🍪

Create file and form parameters the same way you would for `Body` or `Query`:

{* ../../docs_src/request_forms_and_files/tutorial001_an_py39.py hl[10:12] *}

The files and form fields will be uploaded as form data and you will receive the files and form fields.

And you can declare some of the files as `bytes` and some as `UploadFile`.

/// warning

       *
       * TODO(b/112550045): Allocating a single, cheaper listener is (I think) only an optimization.
       * If we make some other optimizations, this one will no longer be necessary. The optimization
       * could actually hurt in some cases, as it forces us to keep all inputs in memory until the
       * final input completes.
       */
      @RetainedLocalRef

You can verify it in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/request-form-models/image01.png">
</div>

## Forbid Extra Form Fields { #forbid-extra-form-fields }

In some special use cases (probably not very common), you might want to **restrict** the form fields to only those declared in the Pydantic model. And **forbid** any **extra** fields.

/// note

## Bodies of arbitrary `dict`s { #bodies-of-arbitrary-dicts }

You can also declare a body as a `dict` with keys of some type and values of some other type.

This way, you don't have to know beforehand what the valid field/attribute names are (as would be the case with Pydantic models).

If for some reason you need to disable automatic conversion of underscores to hyphens, set the parameter `convert_underscores` of `Header` to `False`:

{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning

Before setting `convert_underscores` to `False`, bear in mind that some HTTP proxies and servers disallow the usage of headers with underscores.

///

			// directory" error message. Handle this specifically
			// here.
			return errFileAccessDenied
		}
	}
	return err
}

// Reliably retries os.RemoveAll if for some reason os.RemoveAll returns
// syscall.ENOTEMPTY (children has files).
func reliableRemoveAll(dirPath string) (err error) {
	i := 0
	for {
		// Removes all the directories and files.