// it's all encapsulated here so it appears normalized to the POM builder.

    // We are going to take the project packaging and find all plugin in the default lifecycle and create
    // fully populated Plugin objects, including executions with goals and default configuration taken
    // from the plugin.xml inside a plugin.
    //

{* ../../docs_src/background_tasks/tutorial001_py39.py hl[1,13] *}

**FastAPI** создаст объект типа `BackgroundTasks` для вас и передаст его через этот параметр.

## Создание функции для фоновой задачи { #create-a-task-function }

Создайте функцию, которую нужно запустить как фоновую задачу.

Это обычная функция, которая может принимать параметры.

///

## Criar um middleware { #create-a-middleware }

Para criar um middleware, use o decorador `@app.middleware("http")` logo acima de uma função.

A função middleware recebe:

* A `request`.

Переменные окружения могут быть полезны для работы с **настройками** приложений, как часть **установки** Python и т.д.

## Создание и использование переменных окружения { #create-and-use-env-vars }

Можно **создавать** и использовать переменные окружения в **оболочке (терминале)**, не прибегая к помощи Python:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console

var ErrNoEntriesFound = errors.New("No entries found for this key")

// ErrDomainMissing - Indicates domain is missing
var ErrDomainMissing = errors.New("domain is missing")

const etcdPathSeparator = "/"

// create a new coredns service record for the bucket.
func newCoreDNSMsg(ip string, port string, ttl uint32, t time.Time) ([]byte, error) {
	return json.Marshal(&SrvRecord{
		Host:         ip,
		Port:         json.Number(port),

            parentFile.mkdirs()
            createNewFile()
            text = "Generated javadoc HTML goes here"
        }
    }

    private GradleRunner run(String... args) {
        return GradleRunner.create()
            .withProjectDir(projectDir)
            .withPluginClasspath()
            .withArguments(args)
            .forwardOutput()
    }

    private void assertNoDeadLinks() {

	if err != nil {
		if errors.Is(err, errConfigNotFound) || isErrObjectNotFound(err) {
			return nil
		}
		return err
	}
	if len(data) == 0 {
		// Seems to be empty create a new poolMeta object.
		return nil
	}
	if len(data) <= 4 {
		return fmt.Errorf("poolMeta: no data")
	}
	// Read header
	switch binary.LittleEndian.Uint16(data[0:2]) {
	case poolMetaFormat:
	default:

    // it's all encapsulated here so it appears normalized to the POM builder.

    // We are going to take the project packaging and find all plugins in the default lifecycle and create
    // fully populated Plugin objects, including executions with goals and default configuration taken
    // from the plugin.xml inside a plugin.

    @Override

Mas é a maneira mais simples de focar no lado do servidor de WebSockets e ter um exemplo funcional:

{* ../../docs_src/websockets/tutorial001_py39.py hl[2,6:38,41:43] *}

## Crie um `websocket` { #create-a-websocket }

Em sua aplicação **FastAPI**, crie um `websocket`:

{* ../../docs_src/websockets/tutorial001_py39.py hl[1,46:47] *}

/// note | Detalhes Técnicos

        this.lineData = this.lineDataToElements(options.lineData || []);
        this.loadLines()
        if (!options.noInit) this.init()
    }

    loadLines() {
        // Load all the lines and create the container so that the size is fixed
        // Otherwise it would be changing and the user viewport would be constantly
        // moving as she/he scrolls
        const finish = this.generateFinish()