s3-readstream-virtuali

s3-readstream

AWS S3 Read Stream made easy

Simple wrapper around AWS S3 getObject's grab-by-range call allowing intuitive and stable smart streaming.

• Simple interface for streaming any size file from AWS S3
• Easily speed-up, and slow down, the streaming at any point
• All of the functionaly you love with NodeJS Readable streams
• Drop in replacement for AWS.S3.getObject().createReadStream()

To install the package:

npm install s3-readstream

You can integrate the S3ReadStream class with the aws-sdk package easily:

import * as AWS from 'aws-sdk';
import {S3ReadStream} from 's3-readstream';
// Pass in your AWS S3 credentials
const s3 = new AWS.S3({
  accessKeyId: s3Env.accessKey,
  secretAccessKey: s3Env.secret
});

const bucketParams = {
  Bucket: s3Env.bucket, // S3 Bucket Path
  Key: s3Env.key // S3 file
};

// Check the headobject like normal to get the length of the file
s3.headObject(bucketParams, (error, data) => {
    const options = {
        parameters: bucketParams,
        s3,
        maxLength: data.ContentLength,
        byteRange: 1024 * 1024 * 5 // 5 MiB
    };
    // Instantiate the S3ReadStream in place of s3.getObject().createReadStream()
    const stream = new S3ReadStream(options);
});

To adjust the speed of the stream:

// You can adjust the speed at any point during the stream
stream.adjustByteRange(1024 * 1024 * 10); // 10 MiB

You can alse use this S3ReadStream like any other NodeJS Readable stream, setting an event listener is exactly the same:

stream.on('data', (chunk) => {
  console.log(`read: ${chunk.toString()}`);
});
stream.on('end', () => {
  console.log('end');
});

To work with zipped files:

import {createGunzip} from 'zlib';

const gzip = createGunzip();
// pipe into gzip to unzip files as you stream!
stream.pipe(gzip)

See s3-readstream in action in an HD video streaming app example and read a blog on its origins.