Cors on EnableWebFluxSecurity

SecurityConfig.java

import org.springframework.context.annotation.Bean;
import org.springframework.http.HttpHeaders;
import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
import org.springframework.security.config.web.server.ServerHttpSecurity;
import org.springframework.security.web.server.SecurityWebFilterChain;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.reactive.CorsConfigurationSource;
import org.springframework.web.cors.reactive.UrlBasedCorsConfigurationSource;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

@EnableWebFluxSecurity
public class SecurityConfig {

    @Bean
    public SecurityWebFilterChain securityWebFilterChain(ServerHttpSecurity http) {
        return http.cors(corsSpec -> corsSpec.configurationSource(corsConfigurationSource())).build();
    }

    CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(Collections.singletonList("http://localhost:3000"));
        configuration.setAllowedMethods(Arrays.asList("GET", "PUT", "DELETE", "POST", "OPTIONS", "HEAD"));
        List<String> allowedHeaders = new ArrayList<>();
        allowedHeaders.add(HttpHeaders.ORIGIN);
        allowedHeaders.add(HttpHeaders.ACCESS_CONTROL_REQUEST_METHOD);
        allowedHeaders.add(HttpHeaders.AUTHORIZATION);
        configuration.setAllowedHeaders(allowedHeaders);
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}