return err
	}
	if msg.Flags&FlagCRCxxh3 != 0 {
		h := xxh3.Hash(dst)
		dst = binary.LittleEndian.AppendUint32(dst, uint32(h))
	}
	return c.send(c.ctx, dst)
}

// sendMsg will send
func (c *Connection) sendMsg(conn net.Conn, msg message, payload msgp.MarshalSizer) error {
	if payload != nil {
		if sz := payload.Msgsize(); cap(msg.Payload) < sz {
			PutByteBuffer(msg.Payload)

	entry := errToEntry(ctx, subsystem, err, errKind...)
	sendLog(ctx, entry)
}

func sendLog(ctx context.Context, entry log.Entry) {
	systemTgts := SystemTargets()
	if len(systemTgts) == 0 {
		return
	}

	// Iterate over all logger targets to send the log entry
	for _, t := range systemTgts {
		if err := t.Send(ctx, entry); err != nil {
			if consoleTgt != nil { // Sending to the console never fails

The process that happens when your API app calls the *external API* is named a "callback". Because the software that the external developer wrote sends a request to your API and then your API *calls back*, sending a request to an *external API* (that was probably created by the same developer).

func (m *muxClient) sendLocked(msg message) error {
	dst := GetByteBufferCap(msg.Msgsize())
	msg.Seq = m.SendSeq
	msg.MuxID = m.MuxID
	msg.Flags |= m.BaseFlags
	if debugPrint {
		fmt.Println("Client sending", &msg, "to", m.parent.Remote)
	}
	m.SendSeq++

	dst, err := msg.MarshalMsg(dst)
	if err != nil {
		return err
	}
	if msg.Flags&FlagSubroute != 0 {
		if m.subroute == nil {

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[19:21] *}

...would be run after the the response finishes sending the slow data:

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[30:38] hl[31:33] *}

But as `generate_stream()` doesn't use the database session, it is not really necessary to keep the session open while sending the response.

// any for the associated TargetID
type TargetIDResult struct {
	// ID where the remove or send were initiated.
	ID TargetID
	// Stores any error while removing a target or while sending an event.
	Err error
}

// Remove - closes and removes targets by given target IDs.
func (list *TargetList) Remove(targetIDSet TargetIDSet) {
	list.Lock()
	defer list.Unlock()

	maxWorkers int64

	// workerStartMu sync.Mutex
	lastStarted time.Time

	wg sync.WaitGroup

	// Channel of log entries.
	// Reading logCh must hold read lock on logChMu (to avoid read race)
	// Sending a value on logCh must hold read lock on logChMu (to avoid closing)
	logCh   chan any
	logChMu sync.RWMutex

	// If this webhook is being re-configured we will
	// assign the new webhook target to this field.

type Target struct {
	status int32

	totalMessages  int64
	failedMessages int64

	wg sync.WaitGroup

	// Channel of log entries.
	// Reading logCh must hold read lock on logChMu (to avoid read race)
	// Sending a value on logCh must hold read lock on logChMu (to avoid closing)
	logCh   chan any
	logChMu sync.RWMutex

	// store to persist and replay the logs to the target
	// to avoid missing events when the target is down.

```console
$ pip install python-multipart
```

This is because **OAuth2** uses "form data" for sending the `username` and `password`.

///

Run the example with:

<div class="termy">

```console
$ fastapi dev main.py

    }
    body.awaitSuccess()
    assertThat(log.take()!!)
      .contains("StreamResetException: stream was reset: CANCEL")
  }

  /**
   * We delay sending the last byte of the request body 1500 ms. The 1000 ms read timeout should
   * only elapse 1000 ms after the request body is sent.
   */
  @Test
  fun headersReadTimeoutDoesNotStartUntilLastRequestBodyByteFire() {