mysql - Nodejs服务器崩溃问题

Question

我有一组api，并且我将数据发布到数据库，作为响应，我从数据库中以json 形式获取所需的响应。我面临的问题是，当我第一次发布数据时，它将被发布，第二次我的服务器将崩溃并给出错误:发送后无法设置 header 。我不知道为什么我会收到此错误。请告诉我哪里出错了

router.post('/addcustomerskills', function(req,res) {
    var skill = req.body.skill;
    var skill_id = req.body.skill_id;
    var skill_name = req.body.skill_name;
    var rating = req.body.rating;
    var response = {};

    if (typeof skill ==='undefined') {
        response.token = '2ewerr4';
        response.success = false,
        response.skill = null;
        response.mssg = 'fields cannot be empty';
        res.json(response);
    } else {
        var j =1;
        for (i in skill) {
            var skillObj=skill[i];  
            db.query('INSERT into skill(skill_id,skill_name,rating) values(?,?,?)', [skillObj.skill_id, skillObj.skill_name, skillObj.rating], function(error, rows) {
                if (error) {
                    res.json(error);
                } else {        
                    db.query('select id,skill_id,skill_name,rating FROM skills WHERE skill_id = ?', [skillObj.skill_id], function(error, rows) {
                        response.success = true,
                        //response.skills = rows;
                        response.skills = skill;
                        response.mssg = 'Successfully Updated';
                        if(j === 1) {
                            j = 0;
                            res.json(response);
                        }           
                    })
                }
            });
        }
    }
});

Answer 1

错误:发送后无法设置 header 。

含义很简单，即您多次发送资源。

@SRK 这里的错误是这样的

您有 for 循环，每次查询数据库时都会在其中发送 res 。

for 循环完成后发送回响应。

router.post('/addcustomerskills', function(req,res) {
    var skill = req.body.skill;
    var skill_id = req.body.skill_id;
    var skill_name = req.body.skill_name;
    var rating = req.body.rating;
    var response = {};

    if (typeof skill ==='undefined') {
        response.token = '2ewerr4';
        response.success = false,
        response.skill = null;
        response.mssg = 'fields cannot be empty';
        res.json(response);
    } else {
        var j =1;
        for (i in skill) {
            var skillObj=skill[i];  
            db.query('INSERT into skill(skill_id,skill_name,rating) values(?,?,?)', [skillObj.skill_id, skillObj.skill_name, skillObj.rating], function(error, rows) {
                if (error) {

                } else {        
                    db.query('select id,skill_id,skill_name,rating FROM skills WHERE skill_id = ?', [skillObj.skill_id], function(error, rows) {
                        response.success = true,
                        //response.skills = rows;
                        response.skills = skill;
                        response.mssg = 'Successfully Updated';
                        if(j === 1) {
                            j = 0;

                        }           
                    })
                }
            });
        }
    res.json({"message":"what you want to send"});
    }
});

如果你想处理crush，请将其添加到你的主node.js 文件中

process.on('uncaughtException', (err) => {
  console.log("error",error);
});