Access to XMLHttpRequest at 'http://localhost:88/api/sys/login' from origin 'http://localhost:8001' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
xhr.js?ec6c:178 POST http://localhost:88/api/sys/login net::ERR_FAILED

解決辦法:
在網關配置文件中加入跨域配置：

    @Bean
    public CorsWebFilter corsWebFilter(){
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration corsConfiguration = new CorsConfiguration();

        //1.配置跨域
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedMethod("*");
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.setAllowCredentials(true);

        source.registerCorsConfiguration("/**",corsConfiguration);
        return new CorsWebFilter(source);
    }

注意：

corsConfiguration.addAllowedHeader("*");

即可。
如果做到這一步還是有問題，那么就需要將cookie權限設置

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