// You should not assume that the request is complete until the client receives an End message.
//
// Header specification:
// End messages contain two headers, as follows:
// https://docs.aws.amazon.com/AmazonS3/latest/API/images/s3select-frame-diagram-end.png
//
// Payload specification:
// End messages have no payload.
var endMessage = []byte{
	0, 0, 0, 56, // total byte-length.

            <button onclick="connect(event)">Connect</button>
            <hr>
            <label>Message: <input type="text" id="messageText" autocomplete="off"/></label>
            <button>Send</button>
        </form>
        <ul id='messages'>
        </ul>
        <script>
        var ws = null;
            function connect(event) {
                var itemId = document.getElementById("itemId")

This can be a `Service` or a `Workload`.

The address type has the following goals:
* It should support (but not require) on-demand lookups.
  * Specifically, ztunnel should be able to send a request to the control plane to answer "I got a request to send traffic to 1.1.1.1, what is 1.1.1.1?"

                request.flags2 &= ~ServerMessageBlock.FLAGS2_RESOLVE_PATHS_IN_DFS;
        }
    }
    void send( ServerMessageBlock request,
                    ServerMessageBlock response ) throws SmbException {
        for( ;; ) {
            resolveDfs(request);
            try {
                tree.send( request, response );
                break;
            } catch( DfsReferral dre ) {

}

// Save - Sends event directly without persisting.
func (target ExampleTarget) Save(eventData Event) error {
	return target.send(eventData)
}

// Store - Returns a nil store.
func (target ExampleTarget) Store() TargetStore {
	return nil
}

func (target ExampleTarget) send(eventData Event) error {
	b := make([]byte, 1)
	if _, err := rand.Read(b); err != nil {
		panic(err)
	}

                    Smb2WriteResponse resp = th.send(request, RequestParam.NO_RETRY);
                    cnt = resp.getCount();
                }
                else {
                    SmbComWriteAndX request = new SmbComWriteAndX(th.getConfig(), fh.getFid(), this.fp, len - w - off, b, off, w, null);
                    th.send(request, this.write_andx_resp, RequestParam.NO_RETRY);

    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> tasks: Handle exceptions in the background task code
    end
```

/// info | 说明

只会向客户端发送 **一次响应** ，可能是一个错误响应，也可能是来自 *路由函数* 的响应。

在发送了其中一个响应之后，就无法再发送其他响应了。

///

/// tip | 提示

You will also get autocompletion for the payload to send:

<img src="/img/tutorial/generate-clients/image03.png">

/// tip

Notice the autocompletion for `name` and `price`, that was defined in the FastAPI application, in the `Item` model.

///

You will have inline errors for the data that you send:

<img src="/img/tutorial/generate-clients/image04.png">

        throw complete(e)
      }
    }

    fun <E : IOException?> complete(e: E): E {
      if (completed) return e
      completed = true
      // If the body is closed without reading any bytes send a responseBodyStart() now.
      if (e == null && invokeStartEvent) {
        invokeStartEvent = false
        eventListener.responseBodyStart(call)
      }

///

```Python hl_lines="10"
{!> ../../docs_src/header_param_models/tutorial002.py!}
```

////

If a client tries to send some **extra headers**, they will receive an **error** response.

For example, if the client tries to send a `tool` header with a value of `plumbus`, they will receive an **error** response telling them that the header parameter `tool` is not allowed:

```json
{