client =
      client.newBuilder()
        .dns(FakeDns())
        .build()
    assertFailsWith<UnknownHostException> {
      getResponse(
        Request.Builder()
          .url("http://1234.1.1.1/index.html".toHttpUrl())
          .build(),
      )
    }
  }

  private fun testServerClosesOutput(socketPolicy: SocketPolicy) {
    server.enqueue(
      MockResponse(

### 당신만의 비동기 코드 작성하기

Starlette(그리고 FastAPI)는 <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a>를 기반으로 하고있고, 따라서 파이썬 표준 라이브러리인 <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a> 및 <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>와 호환됩니다.

它看起来像这样：

<img src="/img/tutorial/sql-databases/image02.png">

您还可以使用[SQLite Viewer](https://inloop.github.io/sqlite-viewer/)或[ExtendsClass](https://extendsclass.com/sqlite-browser.html)等在线 SQLite 浏览器。

## 中间件替代数据库会话

如果你不能使用带有`yield`的依赖项——例如，如果你没有使用**Python 3.7**并且不能安装上面提到的**Python 3.6**的“backports” ——你可以使用类似的方法在“中间件”中设置会话。

“中间件”基本上是一个对每个请求都执行的函数，其中一些代码在端点函数之前执行，另一些代码在端点函数之后执行。

 * assigned characters, including important CJK characters and emoji.
 *
 * <p>Supplementary characters are <a
 * href="https://docs.oracle.com/javase/8/docs/api/java/lang/Character.html#supplementary">encoded
 * into a {@code String} using surrogate pairs</a>, and a {@code CharMatcher} treats these just as
 * two separate characters. {@link #countIn} counts each supplementary character as 2 {@code char}s.
 *

erenter","pointerleave","orig","related","rnoInnerhtml","rchecked","rcleanScript","manipulationTarget","disableScript","restoreScript","cloneCopyEvent","dest","udataOld","udataCur","domManip","collection","hasScripts","iNoClone","valueIsFunction","html","_evalUrl","keepData","cleanData","dataAndEvents","deepDataAndEvents","srcElements","destElements","inPage","detach","append","prepend","insertBefore","before","after","replaceWith","replaceChild","appendTo","prependTo","insertAfter","replaceAll"...

    /** The key of the message: {item} must be between {min} and {max}. */
    public static final String CONSTRAINTS_Range_MESSAGE = "{constraints.Range.message}";

    /** The key of the message: {item} may have unsafe html content. */
    public static final String CONSTRAINTS_SafeHtml_MESSAGE = "{constraints.SafeHtml.message}";

    /** The key of the message: script expression "{script}" didn't evaluate to true. */

    }

    /**
     * This supports painless invocation by the Verifier during embedded execution of the core ITs.
     * See <a href="http://maven.apache.org/shared/maven-verifier/xref/org/apache/maven/it/Embedded3xLauncher.html">
     * <code>Embedded3xLauncher</code> in <code>maven-verifier</code></a>
     *
     * @param args CLI args
     * @param workingDirectory working directory
     * @param stdout stdout
     * @param stderr stderr

		metric.VariableLabels[k] = v
	}
	for k, v := range m.Histogram {
		metric.Histogram[k] = v
	}
	return metric
}

// Get - returns cached value always upton the configured TTL,
// once the TTL expires "read()" registered function is called
// to return the new values and updated.
func (g *MetricsGroupV2) Get() (metrics []MetricV2) {
	m, _ := g.metricsCache.Get()
	if len(m) == 0 {
		return []MetricV2{}

                type: boolean
              minimumTtl:
                description: 'For multi hop sessions only: configure the minimum expected
                  TTL for an incoming BFD control packet.'
                format: int32
                maximum: 254
                minimum: 1
                type: integer
              passiveMode:

**FastAPI**を使用している場合、その「最初の」関数が*path operation 関数*であり、FastAPIが正しく実行する方法を知っているので、心配する必要はありません。

しかし、FastAPI以外で `async` / `await` を使用したい場合は、<a href="https://docs.python.org/3/library/asyncio-task.html#coroutine" class="external-link" target="_blank">公式Pythonドキュメントを参照して下さい</a>。

### 非同期コードの他の形式

`async` と `await` を使用するスタイルは、この言語では比較的新しいものです。

非同期コードの操作がはるかに簡単になります。