gzip compression in node.js

var zlib = require('zlib');
var gzip = zlib.createGzip();
var input = 'file not found';
var compressed = '';

zlib.deflate(input, function(err, buffer){
    console.log(buffer);
    console.log(buffer.toString());
    console.log(buffer.toString('base64'));
    compressed = buffer.toString('base64');
    var buffer = new Buffer('eJxLy8xJVcjLL1FIyy/NSwEAJzkFTg==', 'base64');

    zlib.unzip(buffer, function(err, buffer){
        console.log(buffer.toString())
    })
});

console.log(compressed);