reproduction, and distribution of the Work otherwise complies with
      the conditions stated in this License.

   5. Submission of Contributions. Unless You explicitly state otherwise,
      any Contribution intentionally submitted for inclusion in the Work
      by You to the Licensor shall be under the terms and conditions of
      this License, without any additional terms or conditions.

		var wg sync.WaitGroup
		wg.Add(len(clnts))
		onlineServers = 0
		for _, clnt := range clnts {
			go func(clnt *bootstrapRESTClient) {
				defer wg.Done()

				if clnt.gridConn.State() != grid.StateConnected {
					mu.Lock()
					offlineEndpoints = append(offlineEndpoints, fmt.Errorf("%s is unreachable: %w", clnt, grid.ErrDisconnected))
					mu.Unlock()
					return
				}

	// of splitting error text and always pretty printing the
	// red banner along with the error message. Since the error
	// message itself contains some colored text, we needed
	// to use some ANSI control escapes to cursor color state
	// and freely move in the screen.
	for _, line := range strings.Split(errMsg, "\n") {
		if len(line) == 0 {
			// No more text to print, just quit.
			break
		}

		for {

// GetInternalReplicationState is a wrapper method to fetch internal replication state from the map m
func GetInternalReplicationState(m map[string][]byte) ReplicationState {
	m1 := make(map[string]string, len(m))
	for k, v := range m {
		m1[k] = string(v)
	}
	return getInternalReplicationState(m1)
}

// getInternalReplicationState fetches internal replication state from the map m

		// call will report top level prefixes in deleted state, whereas spark/hadoop interpret this as non-empty
		// and throw a 404 exception. This is especially a problem for spark jobs overwriting the same partition
		// repeatedly. This workaround recursively lists the top 3 entries including delete markers to reflect the
		// correct state of the directory in the list results.

			for _, server := range infoMessage.Servers {
				anonEndpoint := anonAddr(server.Endpoint)
				servers = append(servers, madmin.ServerInfo{
					State:    server.State,
					Endpoint: anonEndpoint,
					Uptime:   server.Uptime,
					Version:  server.Version,
					CommitID: server.CommitID,
					Network:  anonymizeNetwork(server.Network),

            crawlerStatusList.add(Constants.READY);
        }

        // run index update
        final IndexUpdater indexUpdater = ComponentUtil.getIndexUpdater();
        indexUpdater.setName("IndexUpdater");
        indexUpdater.setPriority(indexUpdaterPriority);
        indexUpdater.setSessionIdList(sessionIdList);
        indexUpdater.setDaemon(true);
        indexUpdater.setCrawlerList(crawlerList);

        try (final InputStream is = responseData.getResponseBody()) {
            final byte[] data = InputStreamUtil.getBytes(is);
            resultData.setData(data);
            resultData.setEncoding(responseData.getCharSet());
        } catch (final CrawlerSystemException e) {
            throw e;
        } catch (final Exception e) {

我们将`SessionLocal()`请求的创建和处理放在一个`try`块中。

然后我们在finally块中关闭它。

通过这种方式，我们确保数据库会话在请求后始终关闭，即使在处理请求时出现异常也会关闭。

///

### 关于`request.state`

`request.state`是每个`Request`对象的属性。它用于存储附加到请求本身的任意对象，例如本例中的数据库会话。您可以在[Starlette 的关于`Request`state](https://www.starlette.io/requests/#other-state)的文档中了解更多信息。

对于这种情况下，它帮助我们确保在整个请求中使用单个数据库会话，然后关闭（在中间件中）。

### 使用`yield`依赖项与使用中间件的区别

在此处添加**中间件**与`yield`的依赖项的作用效果类似，但也有一些区别：

     * StackOverflowError: We can't reliably call setException(error).
     *
     * - Any kind of Error from a listener. Even if we could distinguish that case (by exposing some
     * extra state from AbstractFuture), our options are limited: A call to setException() would be
     * a no-op. We could log, but if that's what we really want, we should modify