Fastest way to copy a file in Node.js

The project that I am working on (Node.js) implies lots of operations with the file system (copying, reading, writing, etc.).

Which methods are the fastest?

Solution 1:

Use the standard built-in way fs.copyFile:

const fs = require('fs');

// File destination.txt will be created or overwritten by default.
fs.copyFile('source.txt', 'destination.txt', (err) => {
  if (err) throw err;
  console.log('source.txt was copied to destination.txt');
});

If you have to support old end-of-life versions of Node.js - here is how you do it in versions that do not support fs.copyFile:

const fs = require('fs');
fs.createReadStream('test.log').pipe(fs.createWriteStream('newLog.log'));

Solution 2:

Same mechanism, but this adds error handling:

function copyFile(source, target, cb) {
  var cbCalled = false;

  var rd = fs.createReadStream(source);
  rd.on("error", function(err) {
    done(err);
  });
  var wr = fs.createWriteStream(target);
  wr.on("error", function(err) {
    done(err);
  });
  wr.on("close", function(ex) {
    done();
  });
  rd.pipe(wr);

  function done(err) {
    if (!cbCalled) {
      cb(err);
      cbCalled = true;
    }
  }
}

Solution 3:

I was not able to get the createReadStream/createWriteStream method working for some reason, but using the fs-extra npm module it worked right away. I am not sure of the performance difference though.

npm install --save fs-extra

var fs = require('fs-extra');

fs.copySync(path.resolve(__dirname, './init/xxx.json'), 'xxx.json');