Upload an image and save it as base64 - node.js

Question

First in nodejs, I have succeeded to upload an image (using multer) through postman. Now I am trying to save it not as a png/jpg file, but as a base64 encrypted text file on disk. Any suggestions ?
const express=require('express');
const mongoose= require('mongoose');
const bodyparser=require('body-parser');
const cookieParser=require('cookie-parser');
const db=require('./config/config').get(process.env.NODE_ENV);
const multer = require("multer");
const path = require('path');
var fs = require('fs');
const imageStorage = multer.diskStorage({
// Destination to store image
destination: 'images',
filename: (req, file, cb) => {
cb(null, file.fieldname + '_' + Date.now()
+ path.extname(file.originalname))
// file.fieldname is name of the field (image)
// path.extname get the uploaded file extension
}
});
const imageUpload = multer({
storage: imageStorage,
limits: {
fileSize: 1000000 // 1000000 Bytes = 1 MB
},
fileFilter(req, file, cb) {
if (!file.originalname.match(/\.(png|jpg)$/)) {
// upload only png and jpg format
return cb(new Error('Please upload a Image'))
}
cb(undefined, true)
}
})
app.post('/api/uploadPicture', imageUpload.single('picture'), (req, res) => {
const contents = fs.readFileSync(req.file.path, {encoding: 'base64'});
let buff = Buffer.from(contents).toString('base64');
console.log(buff);
res.send(req.file);
}, (error, req, res, next) => {
res.status(400).send({ error: error.message })
})
Thanks ahead !

Answer 1

I've some ready snippets which worked well for me before. But I've commented there the part where you save a file with exact image extension. Instead I've saved the file with "txt" extension as you want (in userController).
routes/main.js
router.post('/image/base64', multerUpload.single('image'), userController.uploadBase64Image);
utils/multer.js
const multer = require('multer');
const path = require('path');
module.exports = multer({
storage: multer.diskStorage({
destination: function (req, file, cb) {
const filePath = path.join(__dirname, './../uploads');
cb(null, filePath);
},
filename: function (req, file, cb) {
const extension = file.mimetype.split('/')[1];
const fileName = (new Date().getTime() / 1000 | 0) + '.' + extension;
cb(null, fileName);
}
}),
limits: {
fileSize: 1024 * 1024 * 2 // MB
},
fileFilter: (req, file, cb) => {
let valid = (file.mimetype === 'image/jpeg' || file.mimetype === 'image/jpg' || file.mimetype === 'image/png');
cb(null, valid);
},
});
controllers/user.js
const fs = require('fs');
const path = require('path');
const port = process.env.APP_PORT; // 3000
const appUrl = process.env.APP_URL; // http://127.0.0.1
const uploadBase64Image = async (req, res, next) => {
try {
const encoded = req.body.image;
const base64ToArray = encoded.split(";base64,");
// const prefix = base64ToArray[0];
// const extension = prefix.replace(/^data:image\//, '');
const extension = 'txt';
// if (extension === 'jpeg' || extension === 'jpg' || extension === 'png')
// {
const imageData = base64ToArray[1];
const fileName = (new Date().getTime() / 1000|0) + '.' + extension;
const imagePath = path.join(__dirname, './../uploads/') + fileName;
fs.writeFileSync(imagePath, imageData, { encoding: 'base64' });
return res.status(201).json({
error: false,
message: "Base64 Image was successfully uploaded.",
url: `${appUrl}:${port}/images/${fileName}`
});
// }
// else {
// return res.status(403).json({
// error: true,
// message: "Base64 data not valid!",
// });
// }
}
catch (e) {
return res.status(403).json({
error: true,
message: e.message,
});
}
}