// 在方法級別允許跨域
@RestController
@RequestMapping("/api")
public class UserController {
    
    @CrossOrigin(origins = "http://example.com")
    @GetMapping("/users")
    public List<User> getUsers() {
        // 方法實現(xiàn)
        return userService.findAll();
    }
    
    @GetMapping("/roles")
    public List<Role> getRoles() {
        // 此方法不允許跨域
        return roleService.findAll();
    }
}

// 在類級別允許跨域
@CrossOrigin(origins = {"http://example.com", "http://localhost:3000"})
@RestController
@RequestMapping("/api/products")
public class ProductController {
    
    @GetMapping
    public List<Product> getAllProducts() {
        // 方法實現(xiàn)
        return productService.findAll();
    }
    
    @GetMapping("/{id}")
    public Product getProduct(@PathVariable Long id) {
        // 方法實現(xiàn)
        return productService.findById(id);
    }
}

@Configuration
public class WebConfig implements WebMvcConfigurer {
    
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/api/**")
                .allowedOrigins("http://example.com", "http://localhost:3000")
                .allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
                .allowedHeaders("*")
                .allowCredentials(true)
                .maxAge(3600); // 1小時內(nèi)不需要再預檢（發(fā)OPTIONS請求）
    }
}

@Configuration
public class CorsConfig {
    
    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration config = new CorsConfiguration();
        
        // 允許的源
        config.addAllowedOrigin("http://example.com");
        config.addAllowedOrigin("http://localhost:3000");
        
        // 允許的HTTP方法
        config.addAllowedMethod("*");
        
        // 允許的頭信息
        config.addAllowedHeader("*");
        
        // 允許攜帶認證信息（Cookie等）
        config.setAllowCredentials(true);
        
        // 預檢請求的有效期，單位為秒
        config.setMaxAge(3600L);
        
        // 對所有URL應用這些配置
        source.registerCorsConfiguration("/**", config);
        
        return new CorsFilter(source);
    }
}

@Configuration
@EnableWebSecurity
public class SecurityConfig {
    
    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
        http
            .cors(Customizer.withDefaults()) // 使用CorsConfigurationSource的默認配置
            .csrf().disable()
            .authorizeHttpRequests(authorize -> authorize
                .requestMatchers("/api/**").authenticated()
                .anyRequest().permitAll()
            )
            .httpBasic(Customizer.withDefaults());
        
        return http.build();
    }
    
    @Bean
    public CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(Arrays.asList("http://example.com", "http://localhost:3000"));
        configuration.setAllowedMethods(Arrays.asList("GET", "POST", "PUT", "DELETE", "OPTIONS"));
        configuration.setAllowedHeaders(Arrays.asList("Authorization", "Content-Type"));
        configuration.setAllowCredentials(true);
        configuration.setMaxAge(3600L);
        
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}

// Spring Cloud Gateway配置
@Configuration
public class GatewayConfig {
    
    @Bean
    public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
        return builder.routes()
                .route("user_service_route", r -> r.path("/api/users/**")
                        .uri("lb://user-service"))
                .route("product_service_route", r -> r.path("/api/products/**")
                        .uri("lb://product-service"))
                .build();
    }
    
    @Bean
    public WebFilter corsFilter() {
        return (ServerWebExchange ctx, WebFilterChain chain) -> {
            ServerHttpRequest request = ctx.getRequest();
            if (CorsUtils.isCorsRequest(request)) {
                ServerHttpResponse response = ctx.getResponse();
                HttpHeaders headers = response.getHeaders();
                headers.add("Access-Control-Allow-Origin", "*");
                headers.add("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
                headers.add("Access-Control-Allow-Headers", "Authorization, Content-Type");
                headers.add("Access-Control-Allow-Credentials", "true");
                headers.add("Access-Control-Max-Age", "3600");
                if (request.getMethod() == HttpMethod.OPTIONS) {
                    response.setStatusCode(HttpStatus.OK);
                    return Mono.empty();
                }
            }
            return chain.filter(ctx);
        };
    }
}

// vue.config.js
module.exports = {
  devServer: {
    proxy: {
      '/api': {
        target: 'http://localhost:8080',
        changeOrigin: true,
        pathRewrite: {
          '^/api': '/api'
        }
      }
    }
  }
}

server {
    listen 80;
    server_name frontend.example.com;
    
    location / {
        root /usr/share/nginx/html;
        index index.html;
        try_files $uri $uri/ /index.html;
    }
    
    location /api/ {
        proxy_pass http://backend.example.com:8080/api/;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}