网站一直出现502 Bad gateway是怎么回事，是一个公司内部系统。chrome的console报错是Failed to load resource: net::ERR_CONNECTION_RESET，系统是 centos 6.5 阿里云服务器，环境是lnmp，请问这种报错一般该怎么排查呢，已经锁定了是下面这一段代码问题。但是我目前还没找到,php是5.5.36

if ($_REQUEST["field"]) { if (trim($_REQUEST['field']) == "all") { $field = is_numeric(trim($_REQUEST['search'])) ? 'name|origin|type|description|estimate_price|gain_rate|gain_cycle|sales_price|product_amount|total_price|estimate_income' : 'name|origin|type|description'; } else { $field = trim($_REQUEST['field']); } $search = empty($_REQUEST['search']) ? '' : trim($_REQUEST['search']); $condition = empty($_REQUEST['condition']) ? 'is' : trim($_REQUEST['condition']); $field_date = M('Fields')->where('(is_main=1 and model="" and form_type="datetime") or (is_main=1 and model="business" and form_type="datetime")')->select(); foreach($field_date as $v){ if ($field == $v['field']) $search = is_numeric($search)?$search:strtotime($search); } if ($this->_request('state')){ $state = $this->_request('state', 'trim'); $address_where[] = '%'.$state.'%'; if($this->_request('city')){ $city = $this->_request('city', 'trim'); $address_where[] = '%'.$city.'%'; if($this->_request('area')){ $area = $this->_request('area', 'trim'); $address_where[] = '%'.$this->_request('area', 'trim').'%'; } } if($search) $address_where[] = '%'.$search.'%'; $params = array('field='.trim($_REQUEST['field']), 'condition='.$condition, 'state='.$this->_request('state','trim'), 'city='.$this->_request('city','trim'),'area='.$this->_request('area','trim'),'search='.$this->_request('search','trim')); if($condition == 'not_contain'){ $where[$field] = array('notlike', $address_where, 'OR'); }else{ $where[$field] = array('like', $address_where, 'AND'); } }else{ $field_date = M('Fields')->where('is_main=1 and (model="" or model="business") and form_type="datetime"')->select(); foreach($field_date as $v){ if($field == $v['field'] || $field == 'customer.create_time' || $field == 'customer.update_time') $search = is_numeric($search)?$search:strtotime($search); } if($field =="customer_id"){ $c_where['name'] = array('like','%'.$search.'%'); $customer_ids = M('Customer')->where($c_where)->getField('customer_id',true); $where[$field] = array('in',$customer_ids); }else{ switch ($condition) { case "is" : $where[$field] = array('eq',$search);break; case "isnot" : $where[$field] = array('neq',$search);break; case "contains" : $where[$field] = array('like','%'.$search.'%');break; case "not_contain" : $where[$field] = array('notlike','%'.$search.'%');break; case "start_with" : $where[$field] = array('like',$search.'%');break; case "end_with" : $where[$field] = array('like','%'.$search);break; case "is_empty" : $where[$field] = array('eq','');break; case "is_not_empty" : $where[$field] = array('neq','');break; case "gt" : $where[$field] = array('gt',$search);break; case "egt" : $where[$field] = array('egt',$search);break; case "lt" : $where[$field] = array('lt',$search);break; case "elt" : $where[$field] = array('elt',$search);break; case "eq" : $where[$field] = array('eq',$search);break; case "neq" : $where[$field] = array('neq',$search);break; case "between" : $where[$field] = array('between',array($search-1,$search+86400));break; case "nbetween" : $where[$field] = array('not between',array($search,$search+86399));break; case "tgt" : $where[$field] = array('gt',$search+86400);break; default : $where[$field] = array('eq',$search); } } $params = array('field='.trim($_REQUEST['field']), 'condition='.$condition, 'search='.$search ); } } $order = empty($order) ? 'business.update_time desc' : $order; if(trim($_GET['act']) == 'excel'){ if(vali_permission('business', 'export')){ $dc_id = $_GET['daochu']; if($dc_id !=''){ $where['business_id'] = array('in',$dc_id); } $current_page = intval($_GET['current_page']); $export_limit = intval($_GET['export_limit']); $limit = ($export_limit*($current_page-1)).','.$export_limit; $businessList = $d_v_business->where($where)->order($order)->limit($limit)->select();println($businessList); session('export_status', 1); $this->excelExport($businessList); }else{ alert('error', L('HAVE NOT PRIVILEGES'), $_SERVER['HTTP_REFERER']); } } if($_GET['listrows']){ $listrows = intval($_GET['listrows']); $params[] = "listrows=" . intval($_GET['listrows']); }else{ $listrows = 15; $params[] = "listrows=15"; } $list = $d_v_business->where($where)->order($order)->page($p.','.$listrows)->select(); $count = $d_v_business->where($where)->count(); import("@.ORG.Page"); $Page = new Page($count,$listrows); if (!empty($_GET['by'])) { $params[] = "by=".trim($_GET['by']); } $this->parameter = implode('&', $params); if ($_GET['desc_order']) { $params[] = "desc_order=" . trim($_GET['desc_order']); } elseif($_GET['asc_order']){ $params[] = "asc_order=" . trim($_GET['asc_order']); } $Page->parameter = implode('&', $params); $this->assign('page', $Page->show()); foreach($list as $key => $value){ $list[$key]['owner'] = D('RoleView')->where('role.role_id = %d', $value['owner_role_id'])->find(); $list[$key]['creator'] = D('RoleView')->where('role.role_id = %d', $value['creator_role_id'])->find(); $list[$key]['customer_name'] = M('customer')->where('customer_id = %s',$value['customer_id'])->getField('name'); $list[$key]['status_name'] = M('BusinessStatus')->where('status_id = %d', $value['status_id'])->getField('name'); if($by == 'deleted') { $list[$key]["delete_role"] = D('RoleView')->where('role.role_id = %d', $value['delete_role_id'])->find(); } } $d_role_view = D('RoleView'); $this->listrows = $listrows; $this->role_list = $d_role_view->where('role.role_id in (%s)', implode(',', $below_ids))->select(); $this->customer_list = M('customer')->where('owner_role_id in (%s)', implode(',', getSubRoleId()))->select(); $this->assign('list',$list); $this->assign('count',$count); $this->search_field_array = getMainFields('business'); $this->field_array = getIndexFields('business'); $this->alert = parseAlert(); $this->display(); }