Also fügen wir sie in ihr eigenes `dependencies`-Modul (`app/dependencies.py`) ein.

Wir werden nun eine einfache Abhängigkeit verwenden, um einen benutzerdefinierten `X-Token`-Header zu lesen:

//// tab | Python 3.9+

```Python hl_lines="3  6-8" title="app/dependencies.py"
{!> ../../docs_src/bigger_applications/app_an_py39/dependencies.py!}
```

////

//// tab | Python 3.8+

&.show { opacity: $modal-backdrop-opacity; }\n}\n\n// Modal header\n// Top section of the modal w/ title and dismiss\n.modal-header {\n  display: flex;\n  align-items: flex-start; // so the close btn always stays on the upper right corner\n  justify-content: space-between; // Put modal header elements (title and dismiss) on opposite ends\n  padding: $modal-header-padding;\n  border-bottom: $modal-header-border-width solid $modal-header-border-color;\n  @include border-top-radius($modal-content-i...

It has a `GET` operation that could return an error.

It has a `POST` operation that could return several errors.

Both *path operations* require an `X-Token` header.

//// tab | Python 3.10+

```Python
{!> ../../docs_src/app_testing/app_b_an_py310/main.py!}
```

////

//// tab | Python 3.9+

```Python

		header, zerr := zip.FileInfoHeader(dummyFileInfo{
			name:    filename,
			size:    int64(sz),
			mode:    0o600,
			modTime: time.Now(),
			isDir:   false,
			sys:     nil,
		})
		if zerr != nil {
			adminLogIf(ctx, zerr)
			return nil
		}
		header.Method = zip.Deflate
		zwriter, zerr := zipWriter.CreateHeader(header)
		if zerr != nil {

        @SuppressWarnings("resource")
        final CsvReader csvReader = new CsvReader(reader, cfg);
        try {
            List<String> list;
            csvReader.readValues(); // ignore header
            while ((list = csvReader.readValues()) != null) {
                final String suggestWord = getValue(list, 0);
                if (StringUtil.isBlank(suggestWord)) {
                    // skip

lc(.25rem - 1px);border-bottom-left-radius:calc(.25rem - 1px)}.card>.card-header+.list-group,.card>.list-group+.card-footer{border-top:0}.card-body{-ms-flex:1 1 auto;flex:1 1 auto;min-height:1px;padding:1.25rem}.card-title{margin-bottom:.75rem}.card-subtitle{margin-top:-.375rem;margin-bottom:0}.card-text:last-child{margin-bottom:0}.card-link:hover{text-decoration:none}.card-link+.card-link{margin-left:1.25rem}.card-header{padding:.75rem 1.25rem;margin-bottom:0;background-color:rgba(0,0,0,.03);border-bottom:1px...

    assertTrue(unmod.descendingSet().contains(4));

    ensureNotDirectlyModifiable(unmod);
    ensureNotDirectlyModifiable(unmod.descendingSet());
    ensureNotDirectlyModifiable(unmod.headSet(2));
    ensureNotDirectlyModifiable(unmod.headSet(2, true));
    ensureNotDirectlyModifiable(unmod.tailSet(2));
    ensureNotDirectlyModifiable(unmod.tailSet(2, true));
    ensureNotDirectlyModifiable(unmod.subSet(1, 3));

* HTTP Basic.
* **OAuth2** (aussi avec **JWT tokens**). Jetez un oeil au tutoriel [OAuth2 avec JWT](tutorial/security/oauth2-jwt.md){.internal-link target=_blank}.
* Clés d'API dans:
    * Le header.
    * Les paramètres de requêtes.
    * Les cookies, etc.

Plus toutes les fonctionnalités de sécurités venant de Starlette (incluant les **cookies de sessions**).

<img src="/img/tutorial/websockets/image04.png">

そして、これらの通信はすべて同じWebSocket接続を使用します。

## 依存関係

WebSocketエンドポイントでは、`fastapi` から以下をインポートして使用できます。

* `Depends`
* `Security`
* `Cookie`
* `Header`
* `Path`
* `Query`

これらは、他のFastAPI エンドポイント/*path operation* の場合と同じように機能します。

```Python hl_lines="58-65  68-83"
{!../../docs_src/websockets/tutorial002.py!}
```

/// info | "情報"

	}
	return false
}

// checkPostPolicy - apply policy conditions and validate input values.
// (http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-HTTPPOSTConstructPolicy.html)
func checkPostPolicy(formValues http.Header, postPolicyForm PostPolicyForm) error {
	// Check if policy document expiry date is still not reached
	if !postPolicyForm.Expiration.After(UTCNow()) {
		return fmt.Errorf("Invalid according to Policy: Policy expired")
	}