Zip Multiple Files from S3 using AWS Lambda Function

index.js

// Lambda S3 Zipper
// http://amiantos.net/zip-multiple-files-on-aws-s3/
//
// Accepts a bundle of data in the format...
// {
//     "bucket": "your-bucket",
//     "destination_key": "zips/test.zip",
//     "files": [
//         {
//             "uri": "...", (options: S3 file key or URL)
//             "filename": "...", (filename of file inside zip)
//             "type": "..." (options: [file, url])
//         }
//     ]
// }
// Saves zip file at "destination_key" location

"use strict";

const AWS = require("aws-sdk");
const awsOptions = {
  region: "us-east-1",
  httpOptions: {
    timeout: 300000 // Matching Lambda function timeout
  }
};
const s3 = new AWS.S3(awsOptions);
const archiver = require("archiver");
const stream = require("stream");
const request = require("request");

const streamTo = (bucket, key, resolve) => {
  var passthrough = new stream.PassThrough();
  s3.upload(
    {
      Bucket: bucket,
      Key: key,
      Body: passthrough,
      ContentType: "application/zip",
      ServerSideEncryption: "AES256"
    },
    (err, data) => {
      if (err) throw err;
      console.log("Zip uploaded");
      resolve();
    }
  ).on("httpUploadProgress", (progress) => {
    console.log(progress);
  });
  return passthrough;
};

// Kudos to this person on GitHub for this getStream solution
// https://github.com/aws/aws-sdk-js/issues/2087#issuecomment-474722151
const getStream = (bucket, key) => {
  let streamCreated = false;
  const passThroughStream = new stream.PassThrough();

  passThroughStream.on("newListener", event => {
    if (!streamCreated && event == "data") {
      const s3Stream = s3
        .getObject({ Bucket: bucket, Key: key })
        .createReadStream();
      s3Stream
        .on("error", err => passThroughStream.emit("error", err))
        .pipe(passThroughStream);

      streamCreated = true;
    }
  });

  return passThroughStream;
};

exports.handler = async (event, context, callback) => {
  var bucket = event["bucket"];
  var destinationKey = event["destination_key"];
  var files = event["files"];

  await new Promise(async (resolve, reject) => {
    var zipStream = streamTo(bucket, destinationKey, resolve);
    zipStream.on("error", reject);

    var archive = archiver("zip");
    archive.on("error", err => {
      throw new Error(err);
    });
    archive.pipe(zipStream);

    for (const file of files) {
      if (file["type"] == "file") {
        archive.append(getStream(bucket, file["uri"]), {
          name: file["filename"]
        });
      } else if (file["type"] == "url") {
        archive.append(request(file["uri"]), { name: file["filename"] });
      }
    }
    archive.finalize();
  }).catch(err => {
    throw new Error(err);
  });

  callback(null, {
    statusCode: 200,
    body: { final_destination: destinationKey }
  });
};

zipkit.io is another way to solve this problem.

Really happy to see how this gist has grown and evolved over the years. Kudos to everyone who has weighed in, offered more code and advice!

I am going to join in and sing praises for @amiantos - you saved my butt today!
I had to write a Lambda to zip thousands of files. The task would just go dark - no zip, no errors. Your V3 script did the trick - well done!

Over 100 folks signed up for zipkit from this gist so we decided to put in the effort in to give it a proper upgrade.

• Rewrote the docs
• Brand new web UI
• New landing page

Feel free to reach out to me directly if anyone needs a hand integrating, cheers!