How to upload a file to GCP bucket in NodeJs

We have recently posted a guide on how we can download files from a GCP bucket and provide it from a REST API. In this article, we will show how we can upload a file to the bucket.

Prerequisites

• Authentication to GCP (gcloud auth login from terminal) or use service account and set env variable like: export GOOGLE_APPLICATION_CREDENTIALS="/path/to/my-service-account-key.json".
• Bucket enabled in GCP
• Type npm install @google-cloud/storage in your terminal

Let's write our bucketHandler.js class

const { Storage } = require("@google-cloud/storage");
const fs = require("fs");

const storage = new Storage();

const bucketName = "algobook";

class BucketHandler {
  async uploadFile(file, fileName, bucketFolder) {
    return new Promise((resolve, reject) => {
      const stream = storage
        .bucket(bucketName)
        .file(`${bucketFolder}/${fileName}`)
        .createWriteStream();

      stream.on("error", (err) => {
        reject(err);
      });

      stream.on("finish", () => {
        resolve("Done");
      });

      stream.end(file);
    });
  }
}

(async () => {
  const file = fs.readFileSync("cat.png");
  const bucketHandler = new BucketHandler();
  await bucketHandler.uploadFile(file, "myCat.png", "example-folder");
})();

module.exports = BucketHandler;

Run the code using this command:

node bucketHandler.js

In this example, we are reading in a local file in the project cat.png and uploading it to the algobook bucket in the example-folder and giving it a new name myCat.png. By running the code, we will now have a file in our bucket called myCat.png.

Navigating to our GCP bucket, we can now see that our file is successfully uploaded.

Summary

All right. So this was a super short guide on how to upload files to our GCP bucket. We used a local file located in our project. If you want to tie this together with perhaps a client application where you upload a file and sending it to an API, we have excellent guides for that as well. I will link to them below.

Upload files in React and send to a REST API

Reading and writing files in NodeJs using express