Working with the Node.js File System

Firstly, we'll import the file system core module const fs = require('fs');

Next, Let's read data from a file

fs.readFile('./notes.md', (err, data) => {
  if (err) {
    console.log(err);
  }
  console.log(data.toString());
});

Great, we'll see how to write to files next, this code will create a new file if the referenced one does not exist

fs.writeFile('./note.md', 'I am a new file', () => {
    console.log('created a new file succesfully')
})

Awesome, now let's delete the file if it already exists, or create it if it does not

if (fs.existsSync('./note.md')) {
  fs.unlink('./note.md', (err) => {
    if (err) {
      console.log(err);
    } else {
      console.log('file deleted');
    }
  });
} else {
  fs.writeFile('./note.md', 'I am a new file', () => {
    console.log('file created');
  });
}

Next, let's work with directories. We'll see how to create a new directory or delete it if it already exists.

if (fs.existsSync('./new-folder')) {
  fs.rmdir('./new-folder', (err) => {
    if (err) {
      console.log(err);
    } else {
      console.log('folder deleted');
    }
  });
} else {
  fs.mkdir('./new-folder', (err) => {
    if (err) {
      console.log(err);
    } else {
      console.log('folder deleted');
    }
  });
}

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