lambda-s3.js

const AWS = require('aws-sdk');

const BUCKET_NAME = 'your-s3-bucket-name';
const s3 = new AWS.S3();

exports.handler = (event, context, callback) => {
  const { name, body } = event;

  s3.putObject({
    Bucket: BUCKET_NAME,
    Key: `${name}.txt`,
    ContentType: 'text/plain',
    Body: body,
  }, (err, data) => {
    if (err) {
      return callback(err);
    }

    callback(null, data);
  });
};