https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

avec un corps JSON :

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

alors *votre API* traitera la facture et, à un moment ultérieur, enverra une requête de callback à `callback_url` (l’*API externe*) :

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

```
https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

使用如下 JSON 请求体：

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

然后，您的 API 就会处理发票，并在某个点之后，发送回调请求至 `callback_url`（外部 API）：

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

JSON 请求体包含如下内容：

```JSON
{

import org.apache.logging.log4j.core.impl.Log4jLogEvent;

/**
 * Log4j rewrite policy that converts ERROR level log events to WARN level for specified loggers.
 * This policy is useful for downgrading the severity of log events from certain loggers
 * to prevent them from being treated as critical errors.
 */

        dependencies {
            testImplementation 'junit:junit:4.13.1'
        }
        
        tasks.named("test").configure {
            maxParallelForks = 4
            testLogging {
                events "standard_out", "failed"
                exceptionFormat "short"
            }
        }
        
        """
        createTest("SimpleTest")
        createTest("SimpleTest2")
        createTest("SimpleTest3")

https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

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
```

 * This class provides a framework for executing scripts and managing shutdown operations.
 */
public abstract class JobExecutor {
    /** Listener to handle shutdown events */
    protected ShutdownListener shutdownListener;

    /**
     * Default constructor.
     */
    public JobExecutor() {
        // Default constructor
    }

    /**

        final List<EventInfo> events = helper.fetchNewEvents();

        assertEquals(2, events.size());
        assertEquals("config_updated", events.get(0).name);
        assertEquals("node2@host2", events.get(0).instanceId);
        assertEquals("*", events.get(0).targetInstanceId);
        assertEquals(5000L, events.get(0).createdTime);
        assertEquals("web_config", events.get(0).data);

Der Prozess besteht normalerweise darin, dass **Sie in Ihrem Code definieren**, welche Nachricht Sie senden möchten, den **Requestbody**.

Sie definieren auch auf irgendeine Weise, in welchen **Momenten** Ihre App diese Requests oder Events senden wird.

 */
package okhttp3.sse

import okhttp3.Response

abstract class EventSourceListener {
  /**
   * Invoked when an event source has been accepted by the remote peer and may begin transmitting
   * events.
   */
  open fun onOpen(
    eventSource: EventSource,
    response: Response,
  ) {
  }

  open fun onEvent(
    eventSource: EventSource,
    id: String?,
    type: String?,
    data: String,

	parsedQueue := queue{}
	if err := d.DecodeElement(&parsedQueue, &start); err != nil {
		return err
	}

	if len(parsedQueue.Events) == 0 {
		return errors.New("missing event name(s)")
	}

	eventStringSet := set.NewStringSet()
	for _, eventName := range parsedQueue.Events {
		if eventStringSet.Contains(eventName.String()) {
			return &ErrDuplicateEventName{eventName}
		}