```Python hl_lines="21  26"
{!../../docs_src/metadata/tutorial004.py!}
```

/// info

✍ 🌅 🔃 🔖 [➡ 🛠️ 📳](path-operation-configuration.md#_3){.internal-link target=_blank}.

///

### ✅ 🩺

🔜, 🚥 👆 ✅ 🩺, 👫 🔜 🎦 🌐 🌖 🗃:

<img src="/img/tutorial/metadata/image02.png">

### ✔ 🔖

✔ 🔠 🔖 🗃 📖 🔬 ✔ 🎦 🩺 🎚.

		return User{}, ErrAccessTokenExpired
	}
	return User{}, fmt.Errorf("Unable to lookup - keycloak user lookup returned %v", resp.Status)
}

// Option is a function type that accepts a pointer Target
type Option func(*KeycloakProvider)

// WithTransport provide custom transport
func WithTransport(transport http.RoundTripper) Option {
	return func(p *KeycloakProvider) {
		p.client = http.Client{

### Es in der Dokumentation ansehen

Jetzt können Sie Ihre Anwendung mit Uvicorn starten und auf <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a> gehen.

Sie werden sehen, dass Ihre Dokumentation die normalen *Pfadoperationen* und jetzt auch einige **Webhooks** enthält:

## Mehr Details

## Mais detalhes

	testenv.MustHaveSymlink(t)

	tmpdir := t.TempDir()

	link := filepath.Join(tmpdir, "link")
	target := tmpdir
	if err := os.Symlink(target, link); err != nil {
		t.Fatal(err)
	}
	fi, err := os.Lstat(link)
	if err != nil {
		t.Fatal(err)
	}

	h, err := FileInfoHeader(fi, target)
	if err != nil {
		t.Fatal(err)
	}
	if g, e := h.Name, fi.Name(); g != e {

Mas por enquanto, vamos verificar essas importantes **ideias conceituais**. Esses conceitos também se aplicam a qualquer outro tipo de API da web. 💡

## Segurança - HTTPS

No [capítulo anterior sobre HTTPS](https.md){.internal-link target=_blank} aprendemos como o HTTPS fornece criptografia para sua API.

Também vimos que o HTTPS normalmente é fornecido por um componente **externo** ao seu servidor de aplicativos, um **Proxy de terminação TLS**.

                return request.getContentType() != null && request.getContentType().startsWith(MULTIPART_FORMDATA_TYPE);
            }

            @Override
            public void handle(String target, HttpServletRequest request, HttpServletResponse response, int dispatch)
                    throws java.io.IOException, ServletException {

```Python hl_lines="14"
{!../../docs_src/handling_errors/tutorial002.py!}
```

## Install custom exception handlers

You can add custom exception handlers with <a href="https://www.starlette.io/exceptions/" class="external-link" target="_blank">the same exception utilities from Starlette</a>.

Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

And you want to handle this exception globally with FastAPI.

        // WEB-INF/classes
        buf.append("WEB-INF");
        buf.append(File.separator);
        buf.append("classes");
        // target/classes
        final String userDir = System.getProperty("user.dir");
        final File targetDir = new File(userDir, "target");
        final File targetClassesDir = new File(targetDir, "classes");
        if (targetClassesDir.isDirectory()) {
            buf.append(cpSeparator);