listener.start(String.format("class %s", classDoc.getName()));
        try {
            Element chapter = parent.getOwnerDocument().createElement("chapter");
            parent.appendChild(chapter);
            chapter.setAttribute("id", classDoc.getId());
            descriptionRenderer.renderTo(classDoc, chapter);
            merge(classDoc, chapter);
        } finally {
            listener.finish();
        }
    }

/// tip

If you want to **learn FastAPI** in a structured way (recommended), go and read the [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} chapter by chapter instead.

In particular, when running on **Kubernetes** you will probably **not** want to use workers and instead run **a single Uvicorn process per container**, but I'll tell you about it later in that chapter.

///

## Multiple Workers

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// https://www.eclipse.org/jetty/documentation/current/alpn-chapter.html#alpn-versions
private fun alpnBootVersionForPatchVersion(patchVersion: Int): String? {
  return when (patchVersion) {
    in 0..24 -> "8.1.0.v20141016"
    in 25..30 -> "8.1.2.v20141202"

        id = className
        simpleName = className.tokenize('.').last()
        this.classMetaData = classMetaData
        this.extensionMetaData = extensionMetaData

        classSection = targetDocument.createElement('chapter')

        classContent.childNodes.each { Node n ->
            classSection << n
        }

        propertiesTable = getTable('Properties')
        propertiesSection = propertiesTable.parentNode

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded`.

But when the form includes files, it is encoded as `multipart/form-data`. You'll read about handling files in the next chapter.

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

///

## Dependencies errors and return values

You can use the same dependency *functions* you use normally.

### Dependency requirements

 * character encoding. UTF-8 is defined in section D92 of <a
 * href="http://www.unicode.org/versions/Unicode6.2.0/ch03.pdf">The Unicode Standard Core
 * Specification, Chapter 3</a>.
 *
 * <p>The variant of UTF-8 implemented by this class is the restricted definition of UTF-8
 * introduced in Unicode 3.1. One implication of this is that it rejects <a

And that function takes parameters in the same way that *path operation functions* do.

/// tip

You'll see what other "things", apart from functions, can be used as dependencies in the next chapter.

///

Whenever a new request arrives, **FastAPI** will take care of:

* Calling your dependency ("dependable") function with the correct parameters.
* Get the result from your function.

That defines the metadata about the main response of a *path operation*.

You can also declare additional responses with their models, status codes, etc.

There's a whole chapter here in the documentation about it, you can read it at [Additional Responses in OpenAPI](additional-responses.md){.internal-link target=_blank}.

## OpenAPI Extra