Securing Spring Boot Applications

Why Security Matters in Spring Boot

As a student learning backend development, I quickly learned that building features is only half the job. Securing those features is equally important. In Spring Boot, security is built-in and powerful—but you need to know how to use it correctly.

Getting Started with Spring Security

Spring Security is a framework that handles authentication and authorization. The easiest way to get started is by adding the Spring Security dependency:

  dependencies {
      implementation 'org.springframework.boot:spring-boot-starter-security'
  }
    

Basic Authentication Example

After adding the dependency, Spring Boot automatically secures all endpoints with HTTP Basic Auth. You’ll get a default login page with a generated password printed in the logs.

Custom Security Configuration

  @Configuration
  @EnableWebSecurity
  public class SecurityConfig {
  
    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
      http.csrf().disable()
          .authorizeHttpRequests()
          .requestMatchers("/api/public").permitAll()
          .anyRequest().authenticated()
          .and()
          .httpBasic();
      return http.build();
    }
  }
    

Using UserDetailsService for Custom Users

  @Service
  public class MyUserDetailsService implements UserDetailsService {
  
    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
      return User.withUsername("student")
                 .password(new BCryptPasswordEncoder().encode("password"))
                 .roles("USER")
                 .build();
    }
  }
    

Encrypting Passwords

  @Bean
  public PasswordEncoder passwordEncoder() {
      return new BCryptPasswordEncoder();
  }
    

Conclusion

Security might feel overwhelming at first, but with Spring Boot it becomes much easier. Start small—secure one route, test user roles—and gradually layer on more advanced techniques like JWT and OAuth. As students, we should build secure apps from day one!