if (userRequest.header("Host") == null) {
      requestBuilder.header("Host", userRequest.url.toHostHeader())
    }

    if (userRequest.header("Connection") == null) {
      requestBuilder.header("Connection", "Keep-Alive")
    }

    // If we add an "Accept-Encoding: gzip" header field we're responsible for also decompressing
    // the transfer stream.
    var transparentGzip = false

type Sub[T Maskable] struct {
	ch     chan T
	types  Mask
	filter func(entry T) bool
}

// PubSub holds publishers and subscribers
type PubSub[T Maskable, M Maskable] struct {
	// atomics, keep at top:
	types          uint64
	numSubscribers int32
	maxSubscribers int32

	// not atomics:
	subs []*Sub[T]
	sync.RWMutex
}

// Publish message to the subscribers.

  rm -f ${tmp_png_prefix}*png
elif [[ x"${cmd_type}" = "xsvg" ]] ; then
  check_command rsvg-convert
  target_file=$(echo "$url" | sed -e "s#^file:/*#/#g")
  rsvg-convert -w 100 -h 100 --keep-aspect-ratio "${target_file}" -o "${output_file}"
elif [[ x"${cmd_type}" = "ximage" ]] ; then
  im_cmd=$(get_imagemagick_cmd)
  if [[ -z "${im_cmd}" ]] ; then
    echo "ImageMagick (convert or magick) does not exist."

 * newHasher().putByte(b1).putBytes(new byte[] { b2, b3 }).hash()
 * newHasher().putBytes(new byte[] { b1, b2, b3 }).hash()
 * }
 *
 * <p>If you wish to avoid this, you should either prepend or append the size of each chunk. Keep in
 * mind that when dealing with char sequences, the encoded form of two concatenated char sequences
 * is not equivalent to the concatenation of their encoded form. Therefore, {@link

## Detalles técnicos { #technical-details }

FastAPI implementa algunas mejores prácticas de SSE desde el primer momento.

{* ../../docs_src/server_sent_events/tutorial005_py310.py hl[14] *}

## Technical Details { #technical-details }

FastAPI implements some SSE best practices out of the box.

        .Builder()
        .add("Connection", "close")
        .add("Transfer-Encoding", "chunked")
        .build()
    val headers2 =
      Headers
        .Builder()
        .add("Connection", "keep-alive")
        .add("Transfer-Encoding", "chunked")
        .build()
    assertThat(headers2).isNotEqualTo(headers1)
    assertThat(headers2.hashCode()).isNotEqualTo(headers1.hashCode().toLong())
  }

	wrappedHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// If server is in shutdown.
		if atomic.LoadUint32(&srv.inShutdown) != 0 {
			// To indicate disable keep-alive, server is shutting down.
			w.Header().Set("Connection", "close")

			// Add 1 minute retry header, incase-client wants to honor it
			w.Header().Set(RetryAfter, "60")

      }
      return false;
    }

    /**
     * Returns a string in the format specified by {@link MoreObjects#toStringHelper(Object)}.
     *
     * <p>After calling this method, you can keep adding more properties to later call toString()
     * again and get a more complete representation of the same object; but properties cannot be
     * removed, so this only allows limited reuse of the helper instance. The helper allows

 * number of streams, dynamically configured with `SETTINGS_MAX_CONCURRENT_STREAMS`. A connection
 * currently carrying zero streams is an idle stream. We keep it alive because reusing an existing
 * connection is typically faster than establishing a new one.
 *
 * When a single logical call requires multiple streams due to redirects or authorization