It is designed to be very simple to use, and to make it very easy for any developer to integrate other components with **FastAPI**.

## What is "Dependency Injection" { #what-is-dependency-injection }

        // To keep this helper simple, return base and let the caller append/pad and inject ctx.
        return base;
    }

    /**
     * Build a full SMB2 packet combining header and provided body, optionally injecting context bytes.
     */
    private static byte[] buildPacket(byte[] header, byte[] body, Integer ctxOffsetFromHeader, byte[] ctxBytes) {
        int totalLen;
        if (ctxOffsetFromHeader != null && ctxBytes != null) {

			// Set decoded length to a large value out of int64 range to simulate parse failure.
			req.Header.Set("x-amz-decoded-content-length", "9999999999999999999999")
		}

		if err != nil {
			t.Fatalf("Error injecting faults into the request: <ERROR> %v.", err)
		}

		// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.

Она спроектирована так, чтобы быть очень простой в использовании и облегчать любому разработчику интеграцию других компонентов с **FastAPI**.

## Что такое инъекция зависимостей («Dependency Injection») { #what-is-dependency-injection }

В программировании **«Dependency Injection»** означает, что у вашего кода (в данном случае у ваших *функций обработки пути*) есть способ объявить вещи, которые требуются для его работы и использования: «зависимости».

Es ist so konzipiert, sehr einfach zu verwenden zu sein und es jedem Entwickler sehr leicht zu machen, andere Komponenten mit **FastAPI** zu integrieren.

## Was ist „Dependency Injection“ { #what-is-dependency-injection }

It achieves something somewhat similar to what can be done with Flask-apispec.

It has an integrated dependency injection system, inspired by Angular 2. It requires pre-registering the "injectables" (like all the other dependency injection systems I know), so, it adds to the verbosity and code repetition.

## Code size { #code-size }

This example might seem verbose. Keep in mind that we are mixing security, data models, utility functions and *path operations* in the same file.

But here's the key point.

The security and dependency injection stuff is written once.

## Codegröße { #code-size }

Dieses Beispiel mag ausführlich erscheinen. Bedenken Sie, dass wir Sicherheit, Datenmodelle, Hilfsfunktionen und *Pfadoperationen* in derselben Datei vermischen.

Aber hier ist der entscheidende Punkt.

Der Code für Sicherheit und Dependency Injection wird einmal geschrieben.

    <artifactId>maven-api</artifactId>
    <version>4.1.0-SNAPSHOT</version>
  </parent>

  <artifactId>maven-api-di</artifactId>
  <name>Maven 4 API :: Dependency Injection</name>
  <description>Maven 4 API - Dependency Injection</description>

  <properties>
    <maven.compiler.proc>none</maven.compiler.proc>
  </properties>

import jakarta.annotation.PostConstruct;
import jakarta.annotation.PreDestroy;
import jakarta.annotation.Resource;

/**
 * A container implementation that manages the lifecycle and dependency injection of components
 * in a crawler application. This container supports both singleton and prototype component
 * instantiation patterns.
 *
 * <p>The container provides mechanisms for:
 * <ul>