Express multer 文件上傳

npm multer 文件上傳

Express app 範本就不寫了，僅記錄一下上傳部分的代碼。

const fs = require('fs');
const express = require('express');
const multer  = require('multer');

const multer_dest = multer({dest: 'public/uploads/'});


const async_route_wrap = fn => {
    return function wrap(...args) {
        const ret = fn(...args);
        const next = args[args.length - 1];
        return Promise.resolve(ret).catch(next);
    };
};


const index = async(req, res) => {

    res.send(`<form method="post" action="/upload" enctype="multipart/form-data">
            <input type="file" name="file1"/>
            <button type="submit">upload</button>
            </form`);
};


const upload = async(req, res) => {

    if (!req.files) return res.json({status: 'failed.'});

    const count = req.files.length;
    for (let i = 0; i < count; i++) {

        const {originalname, size, path: upload_path} = req.files[i];
        const save_path = `./public/uploads/${originalname}`;


        console.log(`Name: ${originalname}, Size: ${size}`);

        fs.renameSync(upload_path, save_path);

        /*
        fs.readFile(file_path, (err, data) => {
            fs.writeFile(new_path, data, (err) => {
                if (err) {
                    console.error(err);
                    throw err;
                } else {
                    if (i + 1 === count) {
                        res.json({status: 'success'});
                    }
                }                
            });
        });
        */
    }

    res.json({
        status: 'success'
    });
};


module.exports = () => {
    const router = express.Router();

    router.get('/', async_route_wrap(index));
    router.post('/upload', multer_dest.any(), async_route_wrap(upload));

    return router;
};

看到註釋的那段讀寫文件的code了，其實multer已經把文件保存在multer_dest.dest的文件夾下麵了，在同一個文件夾下，只需要rename就行了，不需要再讀寫了。