```

mit einem JSON-Körper:

```JSON
{
    "id": "2expen51ve",
    "customer": "Mr. Richie Rich",
    "total": "9999"
}
```

dann verarbeitet *Ihre API* die Rechnung und sendet irgendwann später einen Callback-Request an die `callback_url` (die *externe API*):

```
https://www.external.org/events/invoices/2expen51ve
```

mit einem JSON-Body, der etwa Folgendes enthält:

```JSON
{

 * instances; usually this is [OkHttpClient].
 *
 * ## Web Socket Lifecycle
 *
 * Upon normal operation each web socket progresses through a sequence of states:
 *
 *  * **Connecting:** the initial state of each web socket. Messages may be enqueued but they won't
 *    be transmitted until the web socket is open.
 *

// ScanWords is a split function for a [Scanner] that returns each
// space-separated word of text, with surrounding spaces deleted. It will
// never return an empty string. The definition of space is set by
// unicode.IsSpace.
func ScanWords(data []byte, atEOF bool) (advance int, token []byte, err error) {
	// Skip leading spaces.
	start := 0
	for width := 0; start < len(data); start += width {
		var r rune

    assertEquals(
        "text/plain; something=\"cr@zy\"; something-else=\"crazy with spaces\";"
            + " and-another-thing=\"\"; normal-thing=foo",
        MediaType.create("text", "plain")
            .withParameter("something", "cr@zy")
            .withParameter("something-else", "crazy with spaces")
            .withParameter("and-another-thing", "")
            .withParameter("normal-thing", "foo")

   * documentation.
   */
  public void add(Runnable runnable, Executor executor) {
    // Fail fast on a null. We throw NPE here because the contract of Executor states that it throws
    // NPE on null listener, so we propagate that contract up into the add method as well.
    checkNotNull(runnable, "Runnable was null.");
    checkNotNull(executor, "Executor was null.");

```

////

## Recap

Use multiple Pydantic models and inherit freely for each case.

echoerr () {
  echo 1>&2 "$@"
}
vlog () {
  [[ $verbose || $debug ]] && echoerr "$@"
}
dlog () {
  [[ $debug ]] && echoerr "$@"
}
execRunner () {
  # print the arguments one to a line, quoting any containing spaces
  [[ $verbose || $debug ]] && echo "# Executing command line:" && {
    for arg; do
      if printf "%s\n" "$arg" | grep -q ' '; then
        printf "\"%s\"\n" "$arg"
      else
        printf "%s\n" "$arg"
      fi

	globalLocalDrivesMu.RLock()
	localDrives := cloneDrives(globalLocalDrivesMap)
	globalLocalDrivesMu.RUnlock()

	// Initialize sync waitgroup.
	g := errgroup.WithNErrs(len(localDrives))

	// Disk states slices
	beforeState := make([]string, len(localDrives))
	afterState := make([]string, len(localDrives))

	// Make a volume entry on all underlying storage disks.
	for index := range localDrives {
		index := index

{!> ../../docs_src/body_multiple_params/tutorial004.py!}
```

////

/// info

`Body` hat die gleichen zusätzlichen Validierungs- und Metadaten-Parameter wie `Query` und `Path` und andere, die Sie später kennenlernen.

///

## Einen einzelnen Body-Parameter einbetten

Nehmen wir an, Sie haben nur einen einzelnen `item`-Body-Parameter, ein Pydantic-Modell `Item`.

     * everywhere.
     */
    static final class Sync<V> extends AbstractQueuedSynchronizer {

      private static final long serialVersionUID = 0L;

      /* Valid states. */
      static final int RUNNING = 0;
      static final int COMPLETING = 1;
      static final int COMPLETED = 2;
      static final int CANCELLED = 4;
      static final int INTERRUPTED = 8;