How to upload to S3 Bucket using express-fileupload in Node.js - Easy Way

Table of Contents

Introduction

Node.js is an open-source, cross-platform, back-end JavaScript runtime environment that runs on the V8 engine and executes Javascript code outside the browser. Node.js helps the developer write code that runs on the server side, making it possible for server-side scripting to be achieved.

Learn how to install Node.js:

Express is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications. Let us look at using express-fileupload middleware to upload files to s3 Bucket.

Express-fileupload

The express-fileupload library is a middleware for the Express framework. It provides an easy way to upload files to a designated location. In this tutorial, we will touch on uploading files to s3 Bucket using express-fileupload and answer the dilemma on how to upload to S3 Bucket using express-fileupload in Node.js.

Initializing the application

## scaffolding a express application
mkdir express-file-upload && cd express-file-upload

## initializing a node application and installing all the required dependencies
npm init -y
npm i express express-fileupload aws-sdk dotenv

## creating a starting point for the application
touch index.js .env

## open the project in your preferred code editor
code .

express-fileupload project initialization. — Scaffolded node application

So, now that we have initialized the application let’s move forward with the actual code part of the application, showing us how to upload to S3 Bucket using express-fileupload in Node.js for the Express framework.

Upload to S3 bucket using express-fileupload

const express = require("express");
const upload = require("express-fileupload");
const AWS = require("aws-sdk");
require("dotenv").config();

const app = express();
const PORT = process.env.PORT || 3000;

// using upload middleware
app.use(upload());
app.use(express.json());

// s3 config
const s3 = new AWS.S3({
  accessKeyId: process.env.AWS_ACCESS_KEY_ID, // your AWS access id
  secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY, // your AWS access key
});

// actual function for uploading file
async function uploadFile(file) {
  const params = {
    Bucket: process.env.AWS_BUCKET, // bucket you want to upload to
    Key: `fileupload/scanskill-${Date.now()}-${file.name}`, // put all image to fileupload folder with name scanskill-${Date.now()}${file.name}`
    Body: file.data,
    ACL: "public-read",
  };
  const data = await s3.upload(params).promise();
  return data.Location; // returns the url location
}

app.post("/upload", async (req, res) => {
  // the file when inserted from form-data comes in req.files.file
  const fileLocation = await uploadFile(req.files.file);

  // returning fileupload location
  return res.status(200).json({ location: fileLocation });
});

// starts the express server in the designated port
app.listen(PORT, () => console.log(`server started at PORT: ${PORT}`));

Now testing the application from the postman.

uploading from postman — uploading the file

We send the request to the POST of /upload from postman.

response when file is uploaded. — response when the file is uploaded

When we click the URL the file opens to download.

when url is hit file is downloaded from the s3. — when the file is downloaded from the link

The new file is present in the s3 bucket.

folder created inside the s3 bucket. — A new folder is created inside the s3 bucket

The file is present inside the folder

image present inside the fileupload of the s3 bucket — file present inside the folder of the s3 bucket

Conclusion

Congratulations! you have successfully learned how to upload files in s3 in Express using express-fileupload the package. Fulfilling the requirement on how to upload to S3 Bucket using express-fileupload in Node.js. Now, that we have looked into uploading to an S3 bucket, importing from an S3 bucket is looked into in the beginning parts of this article.

How to upload to S3 Bucket using express-fileupload in Node.js – Easy Way