TIL unzipping a file in node using zlib

POSTED ON: Jan 30, 2022

TAGS: node compression automation

I was working on a automation tool, and the serverless automation tool would grab a piece of content, then upload that content into my AWS S3 bucket as a .gz file.

.gz files are compressed files, zip files.

Since my application needs to read whatever is inside that .gz file, I had to figure out a way to simplify that.

Overall, my application would:

1. fetch the newest files (in .gz format) on AWS S3

2. unzip the file

That was done with the zlib library.

npm i zlib

const zlib = require('zlib');

function decompress(fileIn, fileOut) {
  const unzip = zlib.createUnzip();

  const input = fs.createReadStream(fileIn);
  const output = fs.createWriteStream(fileOut);

  input.pipe(unzip).pipe(output);
}

Then run it like this:

  decompress(item, `filename.json`)

Via:
https://pinoyitsolution.com/2019/05/22/how-to-unzip-multiple-gz-files-using-nodejs-and-zlib-on-windows-10/

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