Question

Using Node.js, show how you would read a file and and write out its contents to a new file in reverse order.

As an example, if the source file had:

Roses are red,

Violets are blue.

If the Trump administration continues to lose cabinet members,

I will not be sad. Boo hoo hoo.

The destination file would have:

I will not be sad. Boo hoo hoo.

If the Trump administration continues to lose cabinet members, Violets are blue.

Roses are red,

Answer 1

First install package:

Install reverse-line-reader and ga package using 
npm i reverse-line-reader fs

Code:

var lineReader = require('reverse-line-reader');
var fs = require("fs");
var content = []

// read all lines from source file and push it to array
lineReader.eachLine('source.txt', function(line) {
  content.push(line);
}).then(function () {
    //write array to destination file
    fs.writeFile('destination.txt',content.join('\n'),function (err) {
       console.log(err ? 'Error :'+err : 'written successfully') }
  );
});

Output:

source.text file:

After executing above code:

destination.txt file: