fedtools-utilities/lib/third/targz.js

Set of utilites for fedtools within nodejs

/**
 * Fedtools justification
 *
 * Adding the option to decompress .tar.gz or .tar
 * instead of always assuming a gzip file.
 * Original: https://github.com/miskun/targz
 *
 */

var
  path = require('path'),
  fs = require('fs'),
  tar = require('tar-fs'),
  zlib = require('zlib');

module.exports = {

  compress: function (opts, callback) {

    // utility
    var error = function (error) {
      callback(error);
    };

    // ensure callback
    callback = callback || function () {};

    // ensure opts
    opts = opts || {};
    opts.tar = opts.tar || {};
    opts.gz = opts.gz || {};

    // default gzip config
    opts.gz.level = opts.gz.level || 6;
    opts.gz.memLevel = opts.gz.memLevel || 6;

    // ensure src and dest
    if (!opts.src) {
      return error('No source for compress!');
    }
    if (!opts.dest) {
      return error('No destination for compress!');
    }

    // go
    process.nextTick(function () {
      tar.pack(opts.src, opts.tar)
        .on('error', error)
        .pipe(zlib.createGzip(opts.gz)
          .on('error', error))
        .pipe(fs.createWriteStream(opts.dest)
          .on('error', error)
          .on('finish', callback));
    });
  },

  decompress: function (opts, callback) {

    // utility
    var error = function (error) {
      callback(error);
    };

    // ensure callback
    callback = callback || function () {};

    // ensure opts
    opts = opts || {};
    opts.tar = opts.tar || {};
    opts.gz = opts.gz || {};

    // ensure src and dest
    if (!opts.src) {
      return error('No source for decompress!');
    }
    if (!opts.dest) {
      return error('No destination for decompress!');
    }

    // find out what to do. Tar, tar.gz, tar.gzip?
    switch (path.extname(opts.src)) {
    case '.gz':
    case '.gzip':
      process.nextTick(function () {
        fs.createReadStream(opts.src)
          .on('error', error)
          .pipe(zlib.createGunzip(opts.gz)
            .on('error', error))
          .pipe(tar.extract(opts.dest, opts.tar)
            .on('error', error)
            .on('finish', callback));
      });
      break;
    case '.tar':
      process.nextTick(function () {
        fs.createReadStream(opts.src)
          .on('error', error)
          .pipe(tar.extract(opts.dest, opts.tar)
            .on('error', error)
            .on('finish', callback));
      });
      break;
    default:
      return error('Invalid source for decompress!');
    }
  }

};