**FastAPI** provides the same `WebSocket` directly just as a convenience for you, the developer. But it comes directly from Starlette.

///

## Await for messages and send messages { #await-for-messages-and-send-messages }

In your WebSocket route you can `await` for messages and send messages.

{* ../../docs_src/websockets/tutorial001_py39.py hl[48:52] *}

You can receive and send binary, text, and JSON data.

## Try it { #try-it }

delivery_mode  (number)    set to '1' for non-persistent or '2' for persistent queue
queue_dir      (path)      staging dir for undelivered messages e.g. '/home/events'
queue_limit    (number)    maximum limit for undelivered messages, defaults to '100000'
comment        (sentence)  optionally add a comment to this setting
```

Or environment variables

```
KEY:

        </form>
        <ul id='messages'>
        </ul>
        <script>
            var ws = new WebSocket("ws://localhost:8000/ws");
            ws.onmessage = function(event) {
                var messages = document.getElementById('messages')
                var message = document.createElement('li')
                var content = document.createTextNode(event.data)
                message.appendChild(content)

                ws.onmessage = function(event) {
                    var messages = document.getElementById('messages')
                    var message = document.createElement('li')
                    var content = document.createTextNode(event.data)
                    message.appendChild(content)
                    messages.appendChild(message)
                };
                event.preventDefault()
            }

        </form>
        <ul id='messages'>
        </ul>
        <script>
            var client_id = Date.now()
            document.querySelector("#ws-id").textContent = client_id;
            var ws = new WebSocket(`ws://localhost:8000/ws/${client_id}`);
            ws.onmessage = function(event) {
                var messages = document.getElementById('messages')
                var message = document.createElement('li')

)

var (
	auditFailedMessagesMD = NewCounterMD(auditFailedMessages,
		"Total number of messages that failed to send since start",
		targetID)
	auditTargetQueueLengthMD = NewGaugeMD(auditTargetQueueLength,
		"Number of unsent messages in queue for target",
		targetID)
	auditTotalMessagesMD = NewCounterMD(auditTotalMessages,
		"Total number of messages sent since start",
		targetID)
)

// loadAuditMetrics - `MetricsLoaderFn` for audit

  chat.loadMore();
  assertEquals("hello, world!", chat.messages());

  chat.loadMore();
  chat.loadMore();
  assertEquals(""
      + "hello, world!\n"
      + "sup, bra?\n"
      + "yo dog", chat.messages());

  // Optional: confirm that your app made the HTTP requests you were expecting.
  RecordedRequest request1 = server.takeRequest();
  assertEquals("/v1/chat/messages/", request1.getUrl().encodedPath());

      }
    }

    try {
      if (pong != null) {
        writer!!.writePong(pong)
      } else if (messageOrClose is Message) {
        val message = messageOrClose
        writer!!.writeMessageFrame(message.formatOpcode, message.data)
        synchronized(this) {
          queueSize -= message.data.size.toLong()
        }
      } else if (messageOrClose is Close) {
        val close = messageOrClose

	}
	if received != "messages received\n" {
		t.Fatalf(`client: expected: "messages received\n", got: %v`, received)
	}

	wg.Wait()
}

// Test deadlineconn handles read timeout properly by reading two messages beyond deadline.
func TestBuffConnReadCheckTimeout(t *testing.T) {
	l, err := net.Listen("tcp", "localhost:0")
	if err != nil {
		t.Fatalf("unable to create listener. %v", err)
	}
	defer l.Close()

	webhookFailedMessagesMD = NewCounterMD(webhookFailedMessages,
		"Number of messages that failed to send",
		allWebhookLabels...)
	webhookQueueLengthMD = NewGaugeMD(webhookQueueLength,
		"Webhook queue length",
		allWebhookLabels...)
	webhookTotalMessagesMD = NewCounterMD(webhookTotalMessages,
		"Total number of messages sent to this target",
		allWebhookLabels...)
)