nginx 设置允许跨越访问，在nginx 配置的server中添加下面内容
add_header 'Access-Control-Allow-Origin' '*' always;
add_header 'Access-Control-Allow-Methods' 'GET, POST, PATCH, DELETE, PUT, OPTIONS';
add_header 'Access-Control-Allow-Credentials' true;
add_header 'Access-Control-Allow-Headers' 'X-Requested-With,Content-Type';