0Pricing
Spring Boot 4 Microservices & REST APIs · Lektion

REST-Endpunkte absichern

Implementieren Sie Spring Security, um Ihre REST-API-Endpunkte vor unbefugtem Zugriff zu schützen.

REST-Endpunkte absichern ist eine kostenlose Spring Boot 4 Microservices & REST APIs-Lektion auf CoddyKit. Dies ist Lektion 2 von 3. Du kannst die komplette Lektion unten kostenlos lesen – dann übst du sie direkt im Browser mit einem integrierten Code-Editor und einem KI-Tutor rund um die Uhr. Sie ist Teil des Spring Boot 4 Microservices & REST APIs-Lernpfads, und dein Fortschritt wird über Web und CoddyKit-App synchronisiert. Der Spring Boot 4 Microservices & REST APIs-Kurs umfasst insgesamt 3 Lektionen.

Teile dieser Lektion wurden noch nicht übersetzt und werden auf Englisch angezeigt.

Why Secure Your API Endpoints?

APIs are gateways to your application's data and functionality. Without proper security, anyone could access, modify, or delete sensitive information.

This lesson will show you how Spring Security helps protect your REST APIs from unauthorized access, ensuring only legitimate users can interact with your services.

Spring Security: Your API's Bouncer

Spring Security is a powerful and highly customizable framework for authentication and access control. For REST APIs, it acts like a bouncer, checking credentials before allowing requests to reach your endpoints.

  • It handles user authentication (who you are).
  • It manages authorization (what you can do).
  • It protects against common web vulnerabilities.

Get Started: Add Dependency

To integrate Spring Security into your Spring Boot project, you need to add its starter dependency to your pom.xml file (if using Maven).

This dependency brings in all the necessary Spring Security components and auto-configuration.

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

Default Security Behavior

Once the Spring Security dependency is added, your Spring Boot application automatically secures all HTTP endpoints!

When you run the app, Spring Security generates a random password and logs it to the console. You'll need this password, along with the default username "user", to access any endpoint.

Customizing Security Rules

The default security is a good start, but you'll want to define your own rules. We do this by creating a security configuration class.

This class uses @Configuration and @EnableWebSecurity, and defines a SecurityFilterChain bean to customize HTTP security.

Try running this basic setup. It will still require authentication, but we'll add users next!

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http.httpBasic(); // Enable basic auth
        http.authorizeHttpRequests(authorize -> authorize
            .anyRequest().authenticated() // All requests need auth
        );
        return http.build();
    }
}

@RestController
class HelloController {
    @GetMapping("/hello")
    public String hello() {
        return "Hello, Secured World!";
    }
}

Defining Users in Memory

For simple applications or testing, you can define users directly in your security configuration using an InMemoryUserDetailsManager bean.

We'll add a user named "user" with password "password" and role "USER". Note: withDefaultPasswordEncoder() is for quick demos; in production, use strong password encoders.

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.provisioning.InMemoryUserDetailsManager;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http.httpBasic();
        http.authorizeHttpRequests(authorize -> authorize
            .anyRequest().authenticated()
        );
        return http.build();
    }

    @Bean
    public UserDetailsService userDetailsService() {
        UserDetails user = User.withDefaultPasswordEncoder()
            .username("user")
            .password("password")
            .roles("USER")
            .build();
        return new InMemoryUserDetailsManager(user);
    }
}

@RestController
class HelloController {
    @GetMapping("/hello")
    public String hello() {
        return "Hello, Secured User!";
    }
}

Endpoint-Specific Authorization

You can define different security rules for different URL patterns using requestMatchers(). The anyRequest().authenticated() rule ensures all other requests require authentication.

Here, we'll make our /hello endpoint require authentication, while other paths will be public.

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.provisioning.InMemoryUserDetailsManager;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http.httpBasic();
        http.authorizeHttpRequests(authorize -> authorize
            .requestMatchers("/hello").authenticated() // /hello requires auth
            .anyRequest().permitAll() // All other requests are public
        );
        return http.build();
    }

    @Bean
    public UserDetailsService userDetailsService() {
        UserDetails user = User.withDefaultPasswordEncoder()
            .username("user")
            .password("password")
            .roles("USER")
            .build();
        return new InMemoryUserDetailsManager(user);
    }
}

@RestController
class HelloController {
    @GetMapping("/hello")
    public String hello() {
        return "Hello, Secured User!";
    }

    @GetMapping("/public")
    public String publicEndpoint() {
        return "Hello, Public!";
    }
}

Public Endpoints with permitAll()

Sometimes you need endpoints that don't require any authentication, like a health check or public information. For these, you use .permitAll().

Order matters! More specific rules (like /public/**) should come before more general ones (like anyRequest()).

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.provisioning.InMemoryUserDetailsManager;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http.httpBasic();
        http.authorizeHttpRequests(authorize -> authorize
            .requestMatchers("/public/**").permitAll() // Public access
            .requestMatchers("/secure/**").authenticated() // Requires authentication
            .anyRequest().denyAll() // Deny all other requests by default
        );
        return http.build();
    }

    @Bean
    public UserDetailsService userDetailsService() {
        UserDetails user = User.withDefaultPasswordEncoder()
            .username("user")
            .password("password")
            .roles("USER")
            .build();
        return new InMemoryUserDetailsManager(user);
    }
}

@RestController
class MyController {
    @GetMapping("/public/info")
    public String publicInfo() {
        return "This is public information!";
    }

    @GetMapping("/secure/data")
    public String secureData() {
        return "This is secure data!";
    }
}

CSRF Protection & REST APIs

CSRF (Cross-Site Request Forgery) protection is crucial for browser-based applications. However, for stateless REST APIs typically consumed by non-browser clients (like mobile apps or other services), CSRF protection is generally not needed and can sometimes cause issues.

You can explicitly disable it in your security configuration:

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.provisioning.InMemoryUserDetailsManager;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http
            .csrf().disable() // Disable CSRF for REST APIs
            .httpBasic();
        http.authorizeHttpRequests(authorize -> authorize
            .requestMatchers("/public/**").permitAll()
            .requestMatchers("/secure/**").authenticated()
            .anyRequest().denyAll()
        );
        return http.build();
    }

    @Bean
    public UserDetailsService userDetailsService() {
        UserDetails user = User.withDefaultPasswordEncoder()
            .username("user")
            .password("password")
            .roles("USER")
            .build();
        return new InMemoryUserDetailsManager(user);
    }
}

@RestController
class MyController {
    @GetMapping("/public/info")
    public String publicInfo() {
        return "This is public information!";
    }

    @GetMapping("/secure/data")
    public String secureData() {
        return "This is secure data!";
    }
}

Quick Check: Security Access

Consider the following SecurityConfig. What would happen if you try to access /api/status without providing any credentials?

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.web.SecurityFilterChain;

@Configuration
@EnableWebSecurity
class SecurityConfig {
    @Bean
    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http
            .csrf().disable()
            .httpBasic();
        http.authorizeHttpRequests(authorize -> authorize
            .requestMatchers("/api/public/**").permitAll()
            .requestMatchers("/api/admin/**").hasRole("ADMIN")
            .anyRequest().authenticated()
        );
        return http.build();
    }
}

Lesson Recap: Securing Endpoints

In this lesson, you learned the foundational steps to secure your Spring Boot REST API endpoints:

  • Added the Spring Security dependency.
  • Understood the default security behavior.
  • Configured a SecurityFilterChain to define custom rules.
  • Set up in-memory users for basic authentication.
  • Used requestMatchers() with permitAll() and authenticated() to define access for specific paths.
  • Disabled CSRF protection for stateless REST APIs.

This knowledge is crucial for building robust and secure microservices!

Häufig gestellte Fragen

Ist die Lektion „REST-Endpunkte absichern“ kostenlos?

Ja — der vollständige Text von „REST-Endpunkte absichern“ ist hier im Web kostenlos zu lesen. Um sie interaktiv zu üben (integrierter Code-Editor und 24/7 KI-Tutor) und den Rest des Spring Boot 4 Microservices & REST APIs-Kurses freizuschalten, upgrade auf CoddyKit PRO. Der Spring Boot 4 Microservices & REST APIs-Kurs umfasst insgesamt 3 Lektionen.

Was lerne ich in „REST-Endpunkte absichern“?

Implementieren Sie Spring Security, um Ihre REST-API-Endpunkte vor unbefugtem Zugriff zu schützen. Du übst Spring Boot 4 Microservices & REST APIs mit praktischem Code, den du direkt im Browser ausführst, und ein 24/7 KI-Tutor beantwortet deine Fragen während du die Lektion bearbeitest.

Brauche ich Erfahrung, um Spring Boot 4 Microservices & REST APIs zu starten?

Keine Vorkenntnisse erforderlich. Spring Boot 4 Microservices & REST APIs auf CoddyKit ist für Anfänger bis fortgeschrittene Lernende strukturiert, sodass du hier starten oder von Anfang an beginnen und in deinem eigenen Tempo voranschreiten kannst. Dies ist Lektion 2 von 3.

Wie lange dauert die Lektion „REST-Endpunkte absichern“?

Die meisten CoddyKit-Lektionen dauern etwa 5–10 Minuten. Jede ist kompakt und interaktiv, sodass du stetig Fortschritte machst und genau dort weitermachst, wo du aufgehört hast – im Web und in der App.

Kann ich in dieser Spring Boot 4 Microservices & REST APIs-Lektion Code schreiben und ausführen?

Ja. Jede Spring Boot 4 Microservices & REST APIs-Lektion enthält einen integrierten Code-Editor, sodass du echten Code direkt in deinem Browser schreibst und ausführst und sofort KI-Feedback erhältst — ohne lokale Einrichtung erforderlich.

Alle Lektionen in diesem Kurs

  1. Grundlagen von OAuth2 und JWT
  2. REST-Endpunkte absichern
  3. Rollenbasierte Zugriffskontrolle
← Zurück zu Spring Boot 4 Microservices & REST APIs