I try to find example where I can send a zip (like via postman) and get this zip in my handler and unzip it so specified folder I didn't find much examples for zipping using express I want to unzip it in path web/app
I try something like the following which doesn't works for me , the zip file is not unzipped in the specified folder, any idea what im doing wrong ?
https://nodejs.org/api/zlib.html#zlib_zlib
var zlib = require('zlib'); var fs = require('fs'); const dir = path.join(__dirname, 'web/app/'); if (req.file.mimetype === 'application/zip') { var unzip = zlib.createUnzip(); var read = fs.createReadStream(req.file); var write = fs.createWriteStream(dir); //Transform stream which is unzipping the zipped file read.pipe(unzip).pipe(write); console.log("unZipped Successfully"); } Any working example will be very helpful, or reference where can I've problem...
while debug I see the that this is when the code failed
var read = fs.createReadStream(req.file);
any idea why?
I've also tried with
var read = fs.createReadStream(req.file.body);
the issue that I dont see the error, reason etc.
when I change it to
var read = fs.createReadStream(req.file.buffer);
the program doesnt exit and i was able to run it until the logger console.log("unZipped Successfully"); but nothing happen...
if there any example with https://www.npmjs.com/package/yauzl yauzl and multer in my context it will be great
update- this is the postman request
4 Answers
Answers 1
Prerequisites:
npm i express unzipper multiparty bluebird- Create
app/webdirectory in your project root (or you can automate creation if you want). - Place all of these files into one directory.
- Node version that supports
async/await(7.6+ as far as I know)
server.js:
const express = require('express'); const Promise = require('bluebird'); const fs = require('fs'); const writeFile = Promise.promisify(fs.writeFile); const { parseRequest, getFile } = require('./multipart'); const { extractFiles } = require('./zip') const EXTRACT_DIR = 'web/app'; const app = express(); const uploadFile = async (req, res, next) => { try { const body = await parseRequest(req); const bodyFile = getFile(body, 'file'); if (!/\.zip$/.test(bodyFile.originalFilename)) { res.status(200).json({ notice: 'not a zip archive, skipping' }) return; } const archiveFiles = await extractFiles(bodyFile); await Promise.each(archiveFiles, async (file) => { await writeFile(EXTRACT_DIR + '/' + file.path, file.buffer); }) res.status(200).end(); } catch (e) { res.status(500).end(); } }; app.post('/files', uploadFile); app.listen(3000, () => { console.log('App is listening on port 3000'); }); multipart.js
const Promise = require('bluebird'); const { Form } = require('multiparty'); function parseRequest (req, options) { return new Promise((resolve, reject) => { const form = new Form(options) form.parse(req, (err, fields, files) => { if (err) { return reject(err); } return resolve({ fields, files }); }); }); } function getFile (body, field) { const bodyFile = body.files[field]; const value = bodyFile ? bodyFile[0] : null; return value || null; } module.exports = { parseRequest, getFile, }; zip.js
const unzip = require('unzipper'); const fs = require('fs'); async function extractFiles (file) { const files = []; await fs.createReadStream(file.path).pipe(unzip.Parse()).on('entry', async entry => { // Cleanup system hidden files (or drop this code if not needed) if ( entry.type !== 'File' || /^__MACOSX/.test(entry.path) || /.DS_Store/.test(entry.path) ) { entry.autodrain() return } const pathArr = entry.path.split('/'); const path = entry.path; const buffer = await entry.buffer(); files.push({ buffer, path, originalFilename: pathArr[pathArr.length - 1] }); }).promise(); return files; } module.exports = { extractFiles, }; Usage:
- Start a server with
node server - Send your file in
filefield in request (keyfilein postman). Example in curlcurl -XPOST -F 'file=@../ttrra-dsp-agency-api/banner.zip' 'localhost:3000/files')
Downsides:
- Unzipped files are stored in buffer so this method doesn't work great and is not recommended for big archives.
Answers 2
First of all, zlib does not support extracting zip files.
I recommend formidable for handling files because
- its battle tested
- most widely used
- avoids writing boilerplate plate code like reading filestream from request, storing and handling errors
- easily configurable
Bare minimal solution for your problem with formidable and extract-zip
const express = require('express'); const fs = require('fs'); const extract = require('extract-zip') const formidable = require('formidable'); const path = require('path'); const uploadDir = path.join(__dirname, '/uploads/'); const extractDir = path.join(__dirname, '/app/'); if (!fs.existsSync(uploadDir)) { fs.mkdirSync(uploadDir); } if (!fs.existsSync(extractDir)) { fs.mkdirSync(extractDir); } const server = express(); const uploadMedia = (req, res, next) => { const form = new formidable.IncomingForm(); // file size limit 100MB. change according to your needs form.maxFileSize = 100 * 1024 * 1024; form.keepExtensions = true; form.multiples = true; form.uploadDir = uploadDir; // collect all form files and fileds and pass to its callback form.parse(req, (err, fields, files) => { // when form parsing fails throw error if (err) return res.status(500).json({ error: err }); if (Object.keys(files).length === 0) return res.status(400).json({ message: "no files uploaded" }); // Iterate all uploaded files and get their path, extension, final extraction path const filesInfo = Object.keys(files).map((key) => { const file = files[key]; const filePath = file.path; const fileExt = path.extname(file.name); const fileName = path.basename(file.name, fileExt); const destDir = path.join(extractDir, fileName); return { filePath, fileExt, destDir }; }); // Check whether uploaded files are zip files const validFiles = filesInfo.every(({ fileExt }) => fileExt === '.zip'); // if uploaded files are not zip files, return error if (!validFiles) return res.status(400).json({ message: "unsupported file type" }); res.status(200).json({ uploaded: true }); // iterate through each file path and extract them filesInfo.forEach(({filePath, destDir}) => { // create directory with timestamp to prevent overwrite same directory names extract(filePath, { dir: `${destDir}_${new Date().getTime()}` }, (err) => { if (err) console.error('extraction failed.'); }); }); }); // runs when new file detected in upload stream form.on('fileBegin', function (name, file) { // get the file base name `index.css.zip` => `index.html` const fileName = path.basename(file.name, path.extname(file.name)); const fileExt = path.extname(file.name); // create files with timestamp to prevent overwrite same file names file.path = path.join(uploadDir, `${fileName}_${new Date().getTime()}${fileExt}`); }); } server.post('/upload', uploadMedia); server.listen(3000, (err) => { if (err) throw err; }); This solution works for single/multiple file uploads. The one problem with this solution is, wrong file types will get uploaded to uploaded directory though server throw error.
To test with postman: 
Answers 3
Without a full example it's tough to say what the real problem is. But according to Express docs it says:
In Express 4, req.files is no longer available on the req object by default. To access uploaded files on the req.files object, use multipart-handling middleware like busboy, multer, formidable, multiparty, connect-multiparty, or pez.
So if you are not using a middleware library to handle uploading files, it's tough to tell what the value of req.file is.
I am also a bit worried that you are trying to use zlib to decompress a zip file, since the library only supports gzip.
The zlib module provides compression functionality implemented using Gzip and Deflate/Inflate
You would want to check for req.file.mimetype === 'application/gzip'
Here are some posts related to unzipping zip files:
Answers 4
This is my code for uploading a file to express server.
//require express library var express = require('express'); //require the express router var router = express.Router(); //require multer for the file uploads var multer = require('multer'); //File Upload var storage = multer.diskStorage({ // destino del fichero destination: function (req, file, cb) { cb(null, './uploads/logo') }, // renombrar fichero filename: function (req, file, cb) { cb(null, file.originalname); } }); var upload = multer({ storage: storage }); router.post("/", upload.array("uploads[]", 1), function (req, res) { res.json('Uploaded logo successfully'); }); module.exports = router; 
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