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))