Node.js : Specify files to unzip with zlib + tar

Question

An installation process is downloading a .tar.gz archive, then extract the files to a destination directory. However, not all the files in the archive are requi

Answer 1

It works similar to the unzip module:

var fs = require('fs');
var tar = require('tar');
var zlib = require('zlib');
var path = require('path');
var mkdirp = require('mkdirp'); // used to create directory tree

var log = console.log;

var tarball = 'path/to/downloaded/archive.tar.gz';
var dest    = 'path/to/destination';

fs.createReadStream(tarball)
  .on('error', log)
  .pipe(zlib.Unzip())
  .pipe(tar.Parse())
  .on('entry', function(entry) {
    if (/\.js$/.test(entry.path)) { // only extract JS files, for instance
      var isDir     = 'Directory' === entry.type;
      var fullpath  = path.join(dest, entry.path);
      var directory = isDir ? fullpath : path.dirname(fullpath);

      mkdirp(directory, function(err) {
        if (err) throw err;
        if (! isDir) { // should really make this an `if (isFile)` check...
          entry.pipe(fs.createWriteStream(fullpath));
        }
      });
    }
  });

Answer 2

You can take a look at this post to find a good solution.

By the way, in the zlib-documentation you'll see that you can specify a "buffer" calling .unzip().