1const multer = require('multer')
2const { extname, resolve } = require('path')
3
4const diskStorage = multer.diskStorage({
5	destination: (req, file, done) => {
6		if (!file) return done(new Error('Upload file error'), null)
7		return done(null, resolve(process.cwd(), 'src/images'))
8	},
9	filename: (req, file, done) => {
10		if (file) {
11			const imagePattern = /(jpg|jpeg|png|gif|svg)/gi
12			const mathExt = extname(file.originalname).replace('.', '')
13
14			if (!imagePattern.test(mathExt)) {
15				return new TypeError('File format is not valid')
16			}
17
18			req.file = file.originalname
19			return done(null, file.originalname)
20		}
21	}
22})
23
24const fileUpload = multer({ storage: diskStorage, limits: 1000000 })
25
26module.exports = { fileUpload }

1var multer = require('multer')
2var upload = multer().single('avatar')
3
4app.post('/profile', function (req, res) {
5  upload(req, res, function (err) {
6    if (err instanceof multer.MulterError) {
7      // A Multer error occurred when uploading.
8    } else if (err) {
9      // An unknown error occurred when uploading.
10    }
11
12    // Everything went fine.
13  })
14})
15

1import { Request } from 'express'
2import multer, { StorageEngine, Multer } from 'multer'
3import { resolve } from 'path'
4
5const diskStorage: StorageEngine = multer.diskStorage({
6	destination: (req: Request, file: Express.Multer.File, done): void => {
7		if (!file) {
8			done(new Error('Upload file error'), null)
9		} else {
10			done(null, resolve(process.cwd(), 'src/images'))
11		}
12	},
13	filename: (req: any, file: Express.Multer.File, done): void => {
14		done(null, file.originalname)
15	}
16})
17
18const fileValidator = (req: any, file: Express.Multer.File, done): void => {
19	const extFile = file.originalname.replace('.', '')
20	const extPattern = /(jpg|jpeg|png|gif|svg|doc)/gi.test(extFile)
21
22	if (!extPattern) {
23		done(new TypeError('File format is not valid'), null)
24	} else {
25		done(null, true)
26	}
27}
28
29export const fileUpload = multer({ storage: diskStorage, limits: { fileSize: 1000000 }, fileFilter: fileValidator }) as Multer

1$ npm install --save multer
2
3var express = require("express");
4var multer = require('multer');
5var upload = multer({dest:'uploads/'});

1const multer = require('multer')
2const { resolve } = require('path')
3const { existsSync, unlink } = require('fs')
4
5const diskStorage = multer.diskStorage({
6	destination: (req, file, done) => {
7		if (!file) return done(new Error('Upload file error'), null)
8
9		const fileExits = existsSync(resolve(process.cwd(), `src/images/${file.originalname}`))
10		if (!fileExits) return done(null, resolve(process.cwd(), 'src/images'))
11
12		unlink(resolve(process.cwd(), `src/images/${file.originalname}`), (error) => {
13			if (error) return done(error)
14			return done(null, resolve(process.cwd(), 'src/images'))
15		})
16	},
17	filename: (req, file, done) => {
18		if (file) {
19			const extFile = file.originalname.replace('.', '')
20			const extPattern = /(jpg|jpeg|png|gif|svg)/gi.test(extFile)
21			if (!extPattern) return done(new TypeError('File format is not valid'), null)
22			req.photo = file.originalname
23			return done(null, file.originalname)
24		}
25	}
26})
27
28const fileUpload = multer({ storage: diskStorage, limits: 1000000 })
29
30module.exports = { fileUpload }

1$ npm install --save multer file upload node