## Server-Sent Events (SSE) { #server-sent-events-sse }

{* ../../docs_src/custom_request_and_route/tutorial003_py310.py hl[26] *}

Nesse exemplo, as *operações de rota* sob o `router` irão usar a classe `TimedRoute` personalizada, e terão um cabeçalho extra `X-Response-Time` na resposta com o tempo que levou para gerar a resposta:

      // We're looking for the smallest charsPerChunk such that bitsPerChar * charsPerChunk is a
      // multiple of 8. A multiple of 8 has 3 low zero bits, so we just need to figure out how many
      // extra zero bits we need to add to the end of bitsPerChar to get 3 in total.
      // The logic here would be wrong for bitsPerChar > 8, but since we require distinct ASCII
      // characters that can't happen.

      //
      // We use two volatile reads. We could reduce this to one by
      // putting our fields into a holder class, but (at least on x86)
      // the extra memory consumption and indirection are more
      // expensive than the extra volatile reads.
      long nanos = expirationNanos;
      long now = System.nanoTime();
      if (nanos == 0 || now - nanos >= 0) {
        synchronized (lock) {

   * Collections#reverseOrder(Comparator)}.
   *
   * <p><b>Java 8+ users:</b> Use {@code thisComparator.reversed()} instead.
   */
  // type parameter <S> lets us avoid the extra <String> in statements like:
  // Ordering<String> o = Ordering.<String>natural().reverse();
  public <S extends T> Ordering<S> reverse() {
    return new ReverseOrdering<>(this);
  }

  /**

    }

    /**
     * Gets a typed value from a document map with a default value.
     *
     * @param <T> the type to convert the value to
     * @param doc the document map to extract the value from
     * @param key the key to look up in the document map
     * @param clazz the class type to convert the value to
     * @param defaultValue the default value to return if the key is not found or conversion fails

/// note

Keep in mind that different tools might have different levels of OpenAPI support.

Some of them might not show all the extra information declared yet, although in most of the cases, the missing feature is already planned for development.

///

You can add a `title`:

其實你也可以在 HTTP `PUT` 操作中使用同一套技巧。

但此處示例使用 `PATCH`，因為它正是為這類情境設計的。

///

/// note | 注意

請注意，輸入的模型依然會被驗證。

因此，如果你希望接收可以省略所有屬性的部分更新，你需要一個所有屬性皆為可選（具預設值或為 `None`）的模型。

為了區分用於更新（全部可選）與用於建立（欄位為必填）的模型，你可以參考 [額外模型](extra-models.md) 中的做法。

				"Signature":      "zOM2YrY/yAQe15VWmT78OlBrK6g=",
				"AWSAccessKeyId": accessKey,
			},
			expected: ErrSignatureDoesNotMatch,
		},
		// (6) Should not error signature matches with extra query params.
		{
			queryParams: map[string]string{
				"response-content-disposition": "attachment; filename=\"4K%2d4M.txt\"",
			},
			expected: ErrNone,
		},

 * certificate.
 *
 * Use of the chain cleaner is necessary to omit unexpected certificates that aren't relevant to
 * the TLS handshake and to extract the trusted CA certificate for the benefit of certificate
 * pinning.
 */
abstract class CertificateChainCleaner {
  @Throws(SSLPeerUnverifiedException::class)
  abstract fun clean(
    chain: List<Certificate>,