Aber in realen Fällen würden Sie bei der Implementierung von Sicherheit mehr Vorteile durch die Verwendung der integrierten [Sicherheits-Werkzeuge (siehe nächstes Kapitel)](../security/index.md){.internal-link target=_blank} erzielen.

///

## Abhängigkeitsfehler und -Rückgabewerte

Sie können dieselben Abhängigkeits-*Funktionen* verwenden, die Sie normalerweise verwenden.

### Abhängigkeitsanforderungen

            options.setDocEncoding("utf-8");
            options.setCharSet("utf-8");

            options.addBooleanOption("-allow-script-in-comments", true);
            options.setFooter("<link rel=\"stylesheet\" href=\"https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/styles/default.min.css\">" +
                "<script src=\"https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/highlight.min.js\"></script>" +

So, the line:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

will not be executed.

/// info

For more information, check <a href="https://docs.python.org/3/library/__main__.html" class="external-link" target="_blank">the official Python docs</a>.

///

## Run your code with your debugger

	for p := top; p != nil; p = p.Link {
		if p.As == obj.ATEXT {
			text = p.From.Sym
		}
		hexes := hexByLine[p.Line()]
		if hexes == "" {
			continue
		}
		delete(hexByLine, p.Line())
		if text == nil {
			t.Errorf("%s: instruction outside TEXT", p)
		}
		size := int64(len(text.P)) - p.Pc
		if p.Link != nil {
			size = p.Link.Pc - p.Pc
		} else if p.Isize != 0 {

browsers\n}\n\n//\n// Prevent `sub` and `sup` elements from affecting the line height in\n// all browsers.\n//\n\nsub,\nsup {\n  position: relative;\n  @include font-size(75%);\n  line-height: 0;\n  vertical-align: baseline;\n}\n\nsub { bottom: -.25em; }\nsup { top: -.5em; }\n\n\n//\n// Links\n//\n\na {\n  color: $link-color;\n  text-decoration: $link-decoration;\n  background-color: transparent; // Remove the gray background on active links in IE 10.\n\n  @include hover() {\n    color: $link-hover-color;\n...

## Details zum `Request`-Objekt

Da **FastAPI** unter der Haube eigentlich **Starlette** ist, mit einer Ebene von mehreren Tools darüber, können Sie Starlette's <a href="https://www.starlette.io/requests/" class="external-link" target="_blank">`Request`</a>-Objekt direkt verwenden, wenn Sie es benötigen.

# 事件：启动 - 关闭

**FastAPI** 支持定义在应用启动前，或应用关闭后执行的事件处理器（函数）。

事件函数既可以声明为异步函数（`async def`），也可以声明为普通函数（`def`）。

/// warning | "警告"

**FastAPI** 只执行主应用中的事件处理器，不执行[子应用 - 挂载](sub-applications.md){.internal-link target=_blank}中的事件处理器。

///

## `startup` 事件

使用 `startup` 事件声明 `app` 启动前运行的函数：

```Python hl_lines="8"
{!../../docs_src/events/tutorial001.py!}
```

本例中，`startup` 事件处理器函数为项目数据库（只是**字典**）提供了一些初始值。

package com.google.common.base;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import com.google.common.collect.Iterables;

/**
 * Microbenchmark for {@link Splitter#on} with char vs String with length == 1.
 *
 * @author Paul Lindner
 */
public class SplitterBenchmark {
  // overall size of string
  @Param({"1", "10", "100", "1000"})
  int length;

import com.google.common.testing.SerializableTester;
import java.util.Set;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests multiset-specific serialization. Can't be invoked directly;
 * please see {@link MultisetTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible // but no-op
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

Mas em situações reais, como implementações de segurança, você pode obter mais vantagens em usar as [Ferramentas de segurança integradas (o próximo capítulo)](../security/index.md){.internal-link target=_blank}.

///

## Erros das dependências e valores de retorno

Você pode utilizar as mesmas *funções* de dependências que você usaria normalmente.

### Requisitos de Dependências