Error in Multer image upload: Unexpected token - in JSON at position 0, SyntaxError: Unexpected token # in JSON at position 0

Asi*_*med 5 rest http node.js express multer

Please help me to get out of this. This is my uploadRouter.js in which I am trying to upload image file from POSTMAN using multer module

const express = require('express');
const mongoose = require('mongoose');
const autheticate = require('../authenticate');
const multer = require('multer')
const bodyParser = require('body-parser');
const storage = multer.diskStorage({
    destination: (req, file, cb) => {
        cb(null, 'public/images');
    },
    filename: (req, file, cb) => {
        cb(null, file.originalname);
    }
});
const imageFileFilter = (req, file, cb) => {
    if(!file.originalname.match(/\.(jpg|jpeg|png|gif)$/)) {
        return cb(new Error('You can upload only image files!'), false);
    }
    cb(null, true);
};
const upload = multer({ storage: storage, fileFilter: imageFileFilter});
//const uploadImgFile = multer().single('imageFile');
const uploadRouter=express.Router();
uploadRouter.use(bodyParser.json());
uploadRouter.route('/')
.get(autheticate.verifyUser,autheticate.verifyAdmin,(req,res,next)=>{
    res.statusCode = 403;
    res.end('GET operation not supported on /imageUpload');
})
.post(autheticate.verifyUser,autheticate.verifyAdmin,upload.single('imageFile'),(req,res,next)=>{
   res.statusCode=200;
   res.setHeader('Content-Type','application/json');
   res.end('End');
})
.put(autheticate.verifyUser,autheticate.verifyAdmin,(req,res,next)=>{
    res.statusCode = 403;
    res.end('GET operation not supported on /imageUpload');
})
.delete(autheticate.verifyUser,autheticate.verifyAdmin,(req,res,next)=>{
    res.statusCode = 403;
    res.end('GET operation not supported on /imageUpload');
})
module.exports = uploadRouter;
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I have set the body type of request message to form-data from POSTMAN,
But after changing body-format when I am uploading the image, the following error is given in POSTMAN

    <body>
        <h1>Unexpected token - in JSON at position 0</h1>
        <h2>400</h2>
        <pre>SyntaxError: Unexpected token # in JSON at position 0
    at JSON.parse (&lt;anonymous&gt;)
    at createStrictSyntaxError (F:\Cousera\Node\coursera-node-confusion-server\node_modules\body-parser\lib\types\json.js:157:10)
    at parse (F:\Cousera\Node\coursera-node-confusion-server\node_modules\body-parser\lib\types\json.js:83:15)
    at F:\Cousera\Node\coursera-node-confusion-server\node_modules\body-parser\lib\read.js:121:18
    at invokeCallback (F:\Cousera\Node\coursera-node-confusion-server\node_modules\raw-body\index.js:224:16)
    at done (F:\Cousera\Node\coursera-node-confusion-server\node_modules\raw-body\index.js:213:7)
    at IncomingMessage.onEnd (F:\Cousera\Node\coursera-node-confusion-server\node_modules\raw-body\index.js:273:7)
    at emitNone (events.js:106:13)
    at IncomingMessage.emit (events.js:208:7)
    at endReadableNT (_stream_readable.js:1055:12)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)</pre>
    </body>
</html>
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Two headers are contained in POSTMAN:
1. Content-Type: 'application/json'
2. Authentication: bearer [[TOKEN]]
Please I am unable to understand the error, I am very new to node.js. Please help me through it

小智 11

当您将 Content-Type 作为 application/json 传递并上传内容类型不是 json 的文件时,会发生此问题。删除此标题,因为它不是必需的。


小智 8

我有一个类似的问题,这就是我解决它的方法。

首先来自客户,不指定 content-type

然后,在发送请求时使用此方法

const file = new FormData();
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如果您只发送文件

file.append('file', file, file.name);
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如果您要发送带有标题之类的文件,那么

file.append('file', file, file.name);
file.append('caption', fileCaption);
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然后使用常量文件向服务器发出发布请求

例如(使用角度)

this.httpClient.post<Addpost>('localhost:3000/add/addFile', file)
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在服务器中,您可以通过以下方式捕获请求

router.post('/addFile', upload.single('file')
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