**FastAPI** 使用依赖项在 OpenAPI 概图（及 API 文档）中定义**安全方案**。

/// info | "技术细节"

**FastAPI** 使用（在依赖项中声明的）类 `OAuth2PasswordBearer` 在 OpenAPI 中定义安全方案，这是因为它继承自 `fastapi.security.oauth2.OAuth2`，而该类又是继承自`fastapi.security.base.SecurityBase`。

所有与 OpenAPI（及 API 文档）集成的安全工具都继承自 `SecurityBase`， 这就是为什么 **FastAPI** 能把它们集成至 OpenAPI 的原因。

///

## 实现的操作

FastAPI 校验请求中的 `Authorization` 请求头，核对请求头的值是不是由 `Bearer ` ＋ 令牌组成， 并返回令牌字符串（`str`）。

import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Base class for tests for emulated {@link AbstractFuture} that allow subclasses to swap in a
 * different "source Future" for {@link AbstractFuture#setFuture} calls.
 */
@GwtCompatible(emulated = true)

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.collect.NullnessCasts.uncheckedCastNullableTToT;
import static com.google.common.collect.NullnessCasts.unsafeNull;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Objects;

  }

  private static <E> ImmutableList<E> copyFromCollection(Collection<? extends E> collection) {
    Object[] elements = collection.toArray();
    switch (elements.length) {
      case 0:
        return of();
      case 1:
        @SuppressWarnings("unchecked") // safe because it came from `collection`
        E element = (E) elements[0];
        return of(element);
      default:

 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Objects;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
import javax.annotation.CheckForNull;

		return 0, err
	}

	// In case we're booting a device or emulator alongside all.bash, wait for
	// it to be ready. adb wait-for-device is not enough, we have to
	// wait for sys.boot_completed.
	if err := adb("wait-for-device", "exec-out", "while [[ -z $(getprop sys.boot_completed) ]]; do sleep 1; done;"); err != nil {
		return 0, err
	}

	// Done once per make.bash.
	if err := adbCopyGoroot(); err != nil {

	SRAW	$1, X6					// 1b531340

	// 4.3: Load and Store Instructions (RV64I)
	LD	(X5), X6				// 03b30200
	LD	4(X5), X6				// 03b34200
	SD	X5, (X6)				// 23305300
	SD	X5, 4(X6)				// 23325300

	// 8.1: Base Counters and Timers (Zicntr)
	RDCYCLE		X5				// f32200c0
	RDTIME		X5				// f32210c0
	RDINSTRET	X5				// f32220c0

	// 13.1: Multiplication Operations
	MUL	X5, X6, X7				// b3035302

With SQLModel, we can use **inheritance** to **avoid duplicating** all the fields in all the cases.

#### `HeroBase` - the base class

Let's start with a `HeroBase` model that has all the **fields that are shared** by all the models:

* `name`
* `age`

{* ../../docs_src/sql_databases/tutorial002_an_py310.py ln[7:9] hl[7:9] *}

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.hash;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;

import com.google.errorprone.annotations.Immutable;
import java.security.Key;
import java.util.ArrayList;
import java.util.Arrays;

{!../../docs_src/sql_databases/sql_app/database.py!}
```

### 创建一个`Base`类

现在我们将使用`declarative_base()`返回一个类。

稍后我们将继承这个类，来创建每个数据库模型或类（ORM 模型）：

```Python hl_lines="13"
{!../../docs_src/sql_databases/sql_app/database.py!}
```

## 创建数据库模型

现在让我们看看文件`sql_app/models.py`。

### 用`Base`类来创建 SQLAlchemy 模型

我们将使用我们之前创建的`Base`类来创建 SQLAlchemy 模型。

/// tip