How do I read the contents of a Node.js stream into a string variable?

Question

I\'m hacking on a Node program that uses smtp-protocol to capture SMTP emails and act on the mail data. The library provides the mail data as a stream, and I don\'t know how

Answer 1

And yet another one for strings using promises:

function getStream(stream) {
  return new Promise(resolve => {
    const chunks = [];

    # Buffer.from is required if chunk is a String, see comments
    stream.on("data", chunk => chunks.push(Buffer.from(chunk)));
    stream.on("end", () => resolve(Buffer.concat(chunks).toString()));
  });
}

Usage:

const stream = fs.createReadStream(__filename);
getStream(stream).then(r=>console.log(r));

remove the .toString() to use with binary Data if required.

update: @AndreiLED correctly pointed out this has problems with strings. I couldn't get a stream returning strings with the version of node I have, but the api notes this is possible.