To start, you need to install the specific S3 Client package from the modular v3 SDK: npm install @aws-sdk/client-s3 Use code with caution. 2. Standard File Download (Saving to Local Disk)
When handling multi-gigabyte files, load them entirely into memory using transformToString() or transformToByteArray() . nodejs download s3 file
: For extremely large files, you can use the Range header to download different parts of a file simultaneously and combine them later. 5. Secure Downloads with Presigned URLs To start, you need to install the specific
const { S3Client, GetObjectCommand } = require("@aws-sdk/client-s3"); const { createWriteStream } = require("fs"); const s3Client = new S3Client({ region: "us-east-1" }); async function downloadFile(bucketName, key, downloadPath) { try { const command = new GetObjectCommand({ Bucket: bucketName, Key: key, }); const response = await s3Client.send(command); // Body is a stream in Node.js for SDK v3 const writeStream = createWriteStream(downloadPath); response.Body.pipe(writeStream); return new Promise((resolve, reject) => { writeStream.on("finish", resolve); writeStream.on("error", reject); }); } catch (err) { console.error("Download failed:", err); } } Use code with caution. 3. Reading Small Files into Memory : For extremely large files, you can use
: You can increase the internal buffer size (e.g., to 256KB) to improve throughput for large transfers at the cost of higher memory usage.