lz的环境是本地访问虚拟机 127.0.0.1:80 端口 用nginx代理express的127.0.0.1:3000 第一次nginx配置：

server {
        listen 80;
        server_name 127.0.0.1;

        access_log      /var/log/nginx/survey_access.log;
        error_log       /var/log/nginx/survey_error.log;

        location /public/ {
                root /home/kevin/nodeSrc/expressSrc/surveyProject;
        }
        location / {
                proxy_pass http://127.0.0.1:3000;
        }

}

但是首页加载时有个自动的ajax请求：

$('#tbl_list_index').bootstrapTable({
               url: '/JS_GetPage_Record', 
               method: 'post', 
               contentType: "application/x-www-form-urlencoded",
               striped: true, 
               cache: false, 
               pagination: true, 
               sortable: false, 
               sortOrder: "asc", 
               queryParams: function (params) {
                   return {
                       pageSize: params.limit,
                       pageIndex: params.offset
                   }
               },
               sidePagination: "server", 
               pageNumber: 1, 
               pageSize: 30,
               pageList: [30, 40, 50, 100], 
               strictSearch: true,
               clickToSelect: true, 
               //height: 600, 
               uniqueId: "Id", 
               cardView: false, 
               detailView: false, 
               smartDisplay: false,
               columns: [...] //省略
           });

请求回来一直是502:

这是nginx打的日志:

请各位指教，多谢