dl-gunzip.js

if (process.argv.length != 3) {
	console.error('usage:',
		process.argv[0],
		process.argv[1],
		'<archive url>');
	process.exit(1);
}

var url = process.argv[2];
var http = require(url.split(':')[0]);
var crypto = require('crypto');
var fs = require('fs');
var zlib = require('zlib');
var path = require('path');

http.get(url, function(res) {
	var filename = path.basename(url, '.gz');
	var output = fs.createWriteStream(filename);
	var md5 = crypto.createHash('md5');
	var gunzip = zlib.createGunzip();
	console.log('downloading archive data.', filename);

	res.pipe(gunzip).pipe(output);

	gunzip.on('data', function(data) {
		md5.update(data);
	});
	gunzip.on('end', function() {
		output.close();
		console.log('done.');
		var md5sum = md5.digest('hex');
		console.log('md5=', md5sum);
	});
}).on('error', function(err) {
	console.log('error', err);
});