### Dependency Injection

FastAPI bao gồm một hệ thống <abbr title='cũng biết đến như là "components", "resources", "services", "providers"'><strong>Dependency Injection</strong></abbr> vô cùng dễ sử dụng nhưng vô cùng mạnh mẽ.

* Thậm chí, các dependency có thể có các dependency khác, tạo thành một phân cấp hoặc **"một đồ thị" của các dependency**.

加上来自 Starlette（包括 **session cookie**）的所有安全特性。

所有的这些都是可复用的工具和组件，可以轻松与你的系统，数据仓库，关系型以及 NoSQL 数据库等等集成。



### 依赖注入

FastAPI 有一个使用非常简单，但是非常强大的<abbr title='也叫做 "components", "resources", "services", "providers"'><strong>依赖注入</strong></abbr>系统。

* 甚至依赖也可以有依赖，创建一个层级或者**“图”依赖**。
* 所有**自动化处理**都由框架完成。
* 所有的依赖关系都可以从请求中获取数据，并且**增加了路径操作**约束和自动文档生成。
* 即使在依赖项中被定义的*路径操作* 也会**自动验证**。
* 支持复杂的用户身份认证系统，**数据库连接**等等。

title: FastAPI — How to add basic and cookie authentication - author: Nils de Bruin author_link: https://medium.com/@nilsdebruin link: https://medium.com/data-rebels/fastapi-google-as-an-external-authentication-provider-3a527672cf33 title: FastAPI — Google as an external authentication provider - author: William Hayes author_link: https://medium.com/@williamhayes link: https://medium.com/@williamhayes/fastapi-starlette-debug-vs-prod-5f7561db3a59 title: FastAPI/Starlette debug vs prod - author: Mukul...

	// more than one disk returned an error.
	// Will not be called if everything operates as expected.
	finished func(errs []error)
}

// listPathRaw will list a path on the provided drives.
// See listPathRawOptions on how results are delivered.
// Directories are always returned.
// Cache will be bypassed.
// Context cancellation will be respected but may take a while to effectuate.

		case f.updates <- flat.clone():
		default:
		}
		f.lastUpdate = time.Now()
	}
}

// scanFolder will scan the provided folder.
// Files found in the folders will be added to f.newCache.
// If final is provided folders will be put into f.newFolders or f.existingFolders.
// If final is not provided the folders found are returned from the function.

   *
   * <p>Note however that if your escaper does not escape characters in the supplementary range, you
   * should either continue to validate the correctness of any surrogate characters encountered or
   * provide a clear warning to users that your escaper does not validate its input.
   *
   * <p>See {@link com.google.common.net.PercentEscaper} for an example.
   *
   * @param csq a sequence of characters

}

// Close - closes underneath connections to NATS server.
func (target *NATSTarget) Close() (err error) {
	close(target.quitCh)
	if target.stanConn != nil {
		// closing the streaming connection does not close the provided NATS connection.
		if target.stanConn.NatsConn() != nil {
			target.stanConn.NatsConn().Close()
		}
		return target.stanConn.Close()
	}

	if target.natsConn != nil {
		target.natsConn.Close()
	}

### Injeção de dependência

FastAPI inclui um sistema de <abbr title='também conhecido como "components", "resources", "services", "providers"'><strong>injeção de dependência</strong></abbr> extremamente fácil de usar, mas extremamente poderoso.

* Mesmo dependências podem ter dependências, criando uma hierarquia ou **"grafo" de dependências**.

   * between pads, hoping that the JVM doesn't reorder them.
   *
   * <p>JVM intrinsics note: It would be possible to use a release-only form of CAS here, if it were
   * provided.
   */
  static final class Cell {
    volatile long p0, p1, p2, p3, p4, p5, p6;
    volatile long value;
    volatile long q0, q1, q2, q3, q4, q5, q6;

    Cell(long x) {
      value = x;
    }

 * plugins should always acquire model builder instances via dependency injection. Developers might want to subclass
 * this factory to provide custom implementations for some of the components used by the model builder, or use the
 * builder API to inject custom instances.
 *
 * @deprecated use {@link org.apache.maven.api.services.ModelBuilder} instead
 */