unggah

This is a convenient wrapper around multer, google cloud storage, and AWS S3 API as a single express middleware to upload file from user to Google Cloud Storage or AWS S3 and S3 compatible providers.

It will change the field for the uploaded file with a url string like

• https://storage.googleapis.com/bucket-name/filename for Google Cloud Storage
• https://bucket-name.s3-ap-southeast-1.amazonaws.com/filename for AWS S3

The url now can be saved to database.

Installation

npm install unggah

Then install either aws-sdk or @google-cloud/storage, depending on what service you're going to use.

npm install aws-sdk
# or 
npm install @google-cloud/storage

Usage

<!-- Don't forget the enctype="multipart/form-data" in your form. -->
<form action="/upload-single" method="post" enctype="multipart/form-data">
  <input type="file" name="file" />
</form>

const express = require('express')
const unggah = require('unggah')
 
const app = express()
 
const upload = unggah({
  limits: {
    fileSize: 1e6 // in bytes
  },
  storage: storage // storage configuration for google cloud storage or S3
})

options:

• limits: limits of uploaded data in object form (similar to limits option in multer)
• storage: setup for cloud storage provider that you want to use (Details in following sections).

It will return an upload object that have 3 methods: (.single(), .array(), and .fields()). You can use all of them just like how you would use multer.

---

Using Google Cloud Storage

Prerequisites

1. Make sure you have a google cloud project with billing enabled.
2. Enable Google Storage API for the project.
3. Create a bucket to store the files.
4. Create a service account and download the credential in JSON format.

storage configurations

• keyFilename: file path for credential that you have downloaded before.
• bucketName: the bucket name that will contain the uploaded file, you can create one through google cloud console.
• rename (optional): it's a string or a function that return a string which will be used as name for files being stored. If omitted it will use the original filename prefixed with the timestamp.

const storage = unggah.gcs({
  keyFilename: '/Users/me/google-credential-keyfile.json',
  bucketName: 'my-bucket',
  rename: (req, file) => {
    return `${Date.now()}-${file.originalname}`  // this is the default
  }
})

note:

To make uploaded files available for public view, add Storage Object Viewer role for allUsers. Step by step instruction can be found here

---

Using AWS S3 or S3 compatible providers

Prerequisites

1. Create a bucket to store the files.
2. Obtain access key id and it's secret for your AWS user account.

storage configurations

• endpoint: url endpoint for your S3 storage (example: s3.ap-southeast-1.amazonaws.com)
• accessKeyId: Access Key ID that you get from prerequisite #2,
• secretAccessKey: Secret Access Key that you get from prerequisite #2,
• bucketName: the bucket name that will contain the uploaded file, you can create one through google cloud console.
• rename (optional): it's a string or a function that return a string which will be used as name for files being stored. If omitted it will use the original filename prefixed with the timestamp.

const storage = unggah.s3({
  endpoint: 's3.ap-southeast-1.amazonaws.com',
  accessKeyId: process.env.AWS_ACCESS_KEY_ID,
  secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY,
  bucketName: 'my-bucket',
  rename: (req, file) => {
    return `${Date.now()}-${file.originalname}`  // this is the default
  }
})

---

// .......
 
const upload = unggah({
  limits: {
    fileSize: 1e6 // in bytes
  },
  storage: storage
})
 
app.post('/upload-single', upload.single('file'), (req, res) => {
  console.log(req.body)
  res.end()
})
 
app.post('/upload-array', upload.array('files'), (req, res) => {
  console.log(req.body)
  res.end()
})
 
app.post('/upload-fields',
  upload.fields([{ name: 'file1' }, { name: 'file2' }]),
  (req, res) => {
    console.log(req.body)
    res.end()
  }
)
 
// .......

Deleting File

The storage object has .delete() method that you can use to delete a file

storage.delete('file.txt')
  .then(() => console.log('deleted'))
  .catch(err => console.log(err.message))