오류 : 헤더를 보낸 후 설정할 수 없습니다.

Question

오류 : 헤더를 보낸 후 설정할 수 없습니다. 나는이 문제를 싫어한다. 왜냐하면 여러 번 해보고 실수를 한 적은 있지만 잘못된 것이기 때문이다. 이 코드는 알았습니다.

const mongoose = require ("mongoose"); 
const Spec = require("./specialist"); 
const Person = require("./person"); 
const Company = require("./company"); 
const bcrypt = require("bcryptjs"); 

module.exports.findUser=function(username,callback){ 
    let query = {email_num:username}; 
    Spec.findOne(query,(err_spec,spec_user)=>{ 
     if(err_spec) throw err_spec; 
     if(!spec_user){ 
      Person.findOne(query,(err_person,person_user)=>{ 
       if(err_person) throw err_person; 
       if(!person_user){ 
        Company.findOne(query,(err_company,company_user)=>{ 
         if(err_company) throw err_company; 
         if(!company_user){ 
          return console.log("Error User Not Found"); 
         } 
         return callback(null,company_user); 
        }); 
       } 
       return callback(null,person_user); 
      }); 
     } 
     return callback(null,spec_user); 
    }); 
}; 
module.exports.comparePassword = function(candidatePassword, hash, callback){ 
    bcrypt.compare(candidatePassword, hash, (err, isMatch) => { 
    if(err) throw err; 
    callback(null, isMatch); 
    }); 
}; 
module.exports.saveToken = function(username,role,token,callback){ 
    let query = {email_num:username}; 
    let updateToken={updatedToken:token}; 
    if(role==="Person-User"){ 
     Person.findOneAndUpdate(query,updateToken,callback); 
    }else if(role==="Specialist-User"){ 
     Spec.findOneAndUpdate(query,updateToken,callback); 
    }else if(role==="Company-User"){ 
     Company.findOneAndUpdate(query,updateToken,callback); 
    }else{ 
     console.log("Something went goes wrong"); 
    } 

} 

3 개의 모음과이 파일을 모두 처리했습니다. 이것이 내 메인 서버 코드입니다.

const express = require("express"); 
const mongoose = require("mongoose"); 
const bodyParser = require("body-parser"); 
const cors = require("cors"); 
const handlebars = require("express-handlebars"); 
const app = express(); 
const passport = require('passport'); 
const cookieParser = require("cookie-parser"); 

const config = require("./config/data"); 
const routes = require("./routes/users"); 
const company = require("./routes/company"); 
const person = require("./routes/person"); 
mongoose.Promise = global.Promise; 

let options = { 
    useMongoClient: true, 
    reconnectTries: Number.MAX_VALUE, 
    reconnectInterval: 500, 
    poolSize: 10, 
    bufferMaxEntries: 0 
    }; 

mongoose.connect(config.database,options); 

let db = mongoose.connection; 
db.on('error', console.error.bind(console, 'connection error:')); 
db.once('open', function() { 
console.log(`DB connected ${new Date()}...`); 
}); 


//app.set('views',__dirname+'views'); 
app.engine('handlebars', handlebars({defaultLayout:false})); 
app.set('view engine', 'handlebars'); 
app.use(bodyParser.json()); 
app.use(bodyParser.urlencoded({ extended: false })); 

app.use(express.static(__dirname + '/public')); 

// app.use(cors()); 
app.use(cookieParser()); 

// Passport Middleware 
// require('./config/passport')(passport); 
app.use(passport.initialize()); 

app.use(passport.session()); 


app.get("/",(req,res)=>{ 
    res.render("index"); 
}); 

// app.get("/forgotPass",(req,res)=>{ 
//  res.render("forgotPass"); 
// }); 
app.get("/user", (req,res)=>{ 
    res.render("user"); 
}); 

app.get("/login",(req,res)=>{ 
    res.render("login"); 
}); 
app.get("/signup",(req,res)=>{ 
    res.render("signup"); 
}); 
app.get("/we",(req,res)=>{ 
    res.render("we"); 
}); 
app.get("/blog",(req,res)=>{ 
    res.render("blog"); 
}); 
app.get("/contactUs",(req,res)=>{ 
    res.render("contactUs"); 
}); 
app.get("/userAsApplicant",(req,res)=>{ 
    res.render("userAsApplicant"); 
}); 
app.use("/users",routes); 
app.use("/company",company); 
app.use("/person",person); 
app.get("/faq",(req,res)=>{ 
    res.render("faq"); 
}); 
app.listen(config.port,()=>{ 
    console.log(`Server running on port ${config.port}....`); 
}); 

또한 많은 양식 핸들러에서 모든 요청에 ​​대해 Ajax를 사용하고 있습니다.

$(function() { 
    $('.subForm').on('submit', function (e) { 
     $.ajax({ 
      type: 'post', 
      url: 'http://localhost:3000/users/spec/register', 
      data: $(this).serialize(), 
      success:function(data){ 
       if(data.success){ 
        location.href="http://localhost:3000/login" 
       }else{ 
        location.href="http://localhost:3000/signup" 
       } 
      } 
     }); 
     e.preventDefault(); 
    }); 

     $('.personAuth').on('submit', function (e) { 
      $.ajax({ 
       type: 'post', 
       url: 'http://localhost:3000/person/register', 
       data: $(this).serialize(), 
       success:function(data){ 
        if(data.success){ 
         location.href="http://localhost:3000/login" 
        }else{ 
         console.log("Chexav"); 
         location.href="http://localhost:3000/signup"; 

        } 
       } 
      }); 
      e.preventDefault(); 
     }); 
     $('.companyAuth').on('submit', function (e) { 
      $.ajax({ 
       type: 'post', 
       url: 'http://localhost:3000/company/register', 
       data: $(this).serialize(), 
       success:function(data){ 
        if(data.success){ 
         location.href="http://localhost:3000/login" 
        }else{ 
         location.href="http://localhost:3000/signup" 
        } 
       } 
      }); 
      e.preventDefault(); 
     }); 
     $('.logInForm').on('submit', function (e) { 
      $.ajax({ 
       type: 'post', 
       url: 'http://localhost:3000/users/authenticate', 
       data: $(this).serialize(), 
       success:function(data){ 
        console.log(data); 
        if(data.token){ 
         localStorage.setItem("Authorization",data.token); 
         $.ajax({ 
          type:'get', 
          url:'http://localhost:3000/users/user', 
          beforeSend: function(xhr){xhr.setRequestHeader('auth', localStorage.getItem("Authorization"));}, 
          success:location.href="http://localhost:3000/users/user" 
         }) 
        } 
       }  
      }); 
      e.preventDefault(); 
     }); 

    }); 

그리고 인증을위한이 경로. 내가 서버를 인증하기 위해 노력하고있어 때 템플릿 엔진으로

const express = require("express"); 
const router = express.Router(); 
const Spec = require("../models/specialist"); 
const jwt = require("jsonwebtoken"); 
const config = require("../config/data"); 
const Model = require("../models/model"); 

    //Registration route 
    router.post("/spec/register",(req,res)=>{ 
     let date=new Date(); 
     let newUser = new Spec({ 
      name:req.body.spec_name, 
      email_num:req.body.spec_email, 
      password:req.body.spec_password, 
      role:"Specialist-User", 
      isActive:true, 
      created:date, 
      updatedToken:"JWT" 

     }); 
     if(newUser.password===req.body.spec_confirmPass){ 
      Spec.getUser(newUser.email_num,(error,user)=>{ 
       if(error) throw error; 
       if(!user){ 
        Spec.addUser(newUser,(err,user)=>{ 
         if(err){ 
          console.log("err"); 
          res.json({success:false,msg:"Somethings Went Wrong"}); 
         } else { 
          res.header("Content-Type","application/json"); 
          res.json({success:true,msg:"User Registered"}); 
         // res.redirect("/login"); 
         } 
        }); 
       }else{ 
        res.json({success:false,msg:"User Already Exists"}); 
       } 
      }); 
     }else{ 
      res.json({success:false,msg:"Password Not Confirmed"}); 
     } 
    }); 


    //Authentication route 
router.post('/authenticate', (req, res,next) => { 
     const email = req.body.email; 
     const password = req.body.password; 
     console.log("UserData"); 
     Model.findUser(email, (err, user) => { 
      console.log("UserData1"); 
      if(err) throw err; 
      if(!user){ 
      return res.json({success: false, msg: 'User not found'}); 
      } 
      Model.comparePassword(password, user.password, (err, isMatch) => { 
      console.log("UserData2"); 
      if(err) throw err; 
      if(isMatch){ 
       let payload={ 
       name:user.name, 
       email:user.email_num, 
       role:user.role, 
       deleted:user.deleted, 
       isActive:user.isActive, 
       created:user.created, 
       }; 
       let token = jwt.sign(payload,config.JWT_SECRET,{ 
        expiresIn:1440 
       }); 

       Model.saveToken(email,user.role,token,(err,success)=>{ 
        if(err) return err; 
        console.log("Success"); 
        // res.setHeader('Authorization',token); 
        // res.cookie('Authorization',token); 
        res.json ({ success: true, token: token }); 
        // res.redirect("https://stackoverflow.com/users/user"); 
       }); 


      } else { 
       return res.json({success: false, msg: 'Wrong password'}); 
      } 
     }); 
    }); 
// res.redirect("/user"); 
}); 

router.use(function(req, res, next) { 
    console.log(req.headers); 
    let token = req.body.token || req.headers['auth'] || req.query.token || req.cookies.Authorization; 
    // console.log(token); 
     if (token) { 
     jwt.verify(token, config.JWT_SECRET, function(err, decoded) {  
      if (err) { 
       console.log(err); 
      return res.json({ success: false, message: 'Failed to authenticate token.' });  
      } else { 
      req.decoded = decoded;  
      next(); 
      res.render("user"); 
      } 
     }); 

     } else { 
     return res.status(403).json({ 
      success: false, 
      message: 'No token provided.' 
     }); 

     } 
    }); 

router.get("/user", (req,res)=>{ 
    res.render("user"); 
}); 




module.exports = router; 

내가 등록 모든 괜찮와 Handlebars.So 사용하지만거야 내가 쿠키를 사용할 수 있다는 것을 알고

Error: Can't set headers after they are sent.

제공합니다,하지만 난 원하는 그걸 막아라. 언어 실수로 불편을 끼쳐 드려 죄송합니다.

Answer 1

Error: Can't set headers after they are sent.

이는 클라이언트 측에 여러 응답을 보내는 것을 의미합니다.

나는 그냥 이런 식으로 마지막 미들웨어에 res.render("user");을 삭제할 필요가 있다고 생각 :

router.use(function(req, res, next) { 
    console.log(req.headers); 
    let token = req.body.token || req.headers['auth'] || req.query.token || req.cookies.Authorization; 
    // console.log(token); 
     if (token) { 
     jwt.verify(token, config.JWT_SECRET, function(err, decoded) {  
      if (err) { 
       console.log(err); 
      return res.json({ success: false, message: 'Failed to authenticate token.' });  
      } else { 
      req.decoded = decoded; 
      // Go next and delete res 
      next(); 
      // res.render("user"); 
      } 
     }); 

     } else { 
     return res.status(403).json({ 
      success: false, 
      message: 'No token provided.' 
     }); 

     } 
    }); 

는 도움이되기를 바랍니다.