///

```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
{

	retryTicker := time.NewTicker(retryInterval)
	defer retryTicker.Stop()

	send := func(key Key) bool {
		for {
			err := target.SendFromStore(key)
			if err == nil {
				break
			}

			logger(
				context.Background(),
				fmt.Errorf("unable to send log entry to '%s' err '%w'", target.Name(), err),
				target.Name(),
			)

			select {

# ----------------------------------------------------------
#                                                      Mail
#                                                     ------
# Does it send mock mail? (true: no send actually, logging only)
mail.send.mock = true

# SMTP server settings for main: host:port
mail.smtp.server.main.host.and.port = localhost:25

# The prefix of subject to show test environment or not

---
name: Feature request
about: Suggest an idea
title: ''
labels: enhancement
assignees: ''

---

Start by telling us what problem you’re trying to solve. Often a solution already exists!

                    req.setCreateDisposition(Smb2CreateRequest.FILE_OPEN);
                    req.chain(new Smb2CloseRequest(th.getConfig(), fileName));
                    th.send(req);
                }
                else {
                    th.send(new SmbComDeleteDirectory(th.getConfig(), fileName), new SmbComBlankResponse(th.getConfig()));
                }
            }
            else {

                    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);

		desc: prometheus.NewDesc("minio_stats", "Statistics exposed by MinIO server", nil, nil),
	}
}

// minioCollector is the Custom Collector
type minioCollector struct {
	desc *prometheus.Desc
}

// Describe sends the super-set of all possible descriptors of metrics
func (c *minioCollector) Describe(ch chan<- *prometheus.Desc) {
	ch <- c.desc
}

// Collect is called by the Prometheus registry when collecting metrics.

def get_query(background_tasks: BackgroundTasks, q: Union[str, None] = None):
    if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(
    email: str, background_tasks: BackgroundTasks, q: str = Depends(get_query)
):
    message = f"message to {email}\n"
    background_tasks.add_task(write_log, message)

            <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")

            <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")