SecurityConfig.java

@Configuration
@EnableWebSecurity
public class SecurityConfig {

    @Value("${jwt.public.key}")
    RSAPublicKey publicKey;

    @Value("${jwt.private.key}")
    RSAPrivateKey privateKey;


    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {

        http.csrf(csrf -> csrf.disable())
            .authorizeHttpRequests(auth -> auth
                .requestMatchers("/authenticate").permitAll()
                .anyRequest().authenticated()
            )
            .httpBasic(Customizer.withDefaults())
            .oauth2ResourceServer(conf -> conf.jwt(Customizer.withDefaults()));

        return http.build();

    }

    @Bean
    public JwtDecoder jwtDecoder(){
       return NimbusJwtDecoder.withPublicKey(publicKey).build();
    }

    @Bean
    public JwtEncoder jwtEncoder(){
        var jwk = new RSAKey.Builder(publicKey).privateKey(privateKey).build();
        var jwks = new ImmutableJWKSet<>(new JWKSet(jwk));
        
        return new NimbusJwtEncoder(jwks);
    }

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