Based on the answer by @peteb, but using Promises and Async/Await:
const AWS = require('aws-sdk');
const s3 = new AWS.S3();
async function getObject (bucket, objectKey) {
try {
const params = {
Bucket: bucket,
Key: objectKey
}
const data = await s3.getObject(params).promise();
return data.Body.toString('utf-8');
} catch (e) {
throw new Error(`Could not retrieve file from S3: ${e.message}`)
}
}
// To retrieve you need to use `await getObject()` or `getObject().then()`
getObject('my-bucket', 'path/to/the/object.txt').then(...);