DennisBB » Programming

Don’t Use FTP, Use SFTP

Dennis — Mon, 10 May 2010 07:03:39 +0000

Don’t use FTP. This is an old protocol that works badly with firewalls and transfers files over UDP which doesn’t guarantee that they’ll be transfered without errors. Besides that, it sends your password in a clear text over the internet which makes it vulnerable to sniffing.

Use SFTP (SSH File Transfer Protocol) which sends everything over ssh encrypted connection and uses TCP for file transfers that ensures your files will be received the same as they were sent. And you don’t need to have 23 (ftp) port available, since sftp works over 22, which eliminates another security vulnerability.

Ruby-debug and Ruby 1.9

Dennis — Wed, 17 Mar 2010 15:07:38 +0000

Ruby-debug still doesn’t support ruby 1.9 and I doubt it will ever be. Instead we have ruby-debug19 gem now. So if you are using ruby 1.9 and you need to debug your rails apps, install it.

sudo gem install ruby-debug19

Currently Rails 3 beta 1 complains that it can’t find ruby-debug gem when you run the server with debugging enabled. Just add ruby-debug19 gem to your Gemfile and it’ll work.

gem "ruby-debug19"

Web Site Validators

Dennis — Mon, 03 Aug 2009 05:44:06 +0000

Here is a list of web site validators that you can bookmark, so not to search for them every time you need them.

http://validator.w3.org/ The W3C Markup Validation Service

http://jigsaw.w3.org/css-validator/ The W3C CSS Validation Service

http://www.w3.org/2003/12/semantic-extractor.html Semantic data extractor

If you know of any more, add them in comments.

Ajax in real XHTML

Dennis — Mon, 20 Apr 2009 15:37:36 +0000

I’ve been workin today on Live Search for this web site. It uses Ajax and since this site is made in real XHTML, JavaScript works in xml mode.

When you work with JavaScript in real XHTML sites sometimes things are different than what they used to be. For example, you make an Ajax call and got transport.responseXML object. This is what you do to add that xml to your code.

var content = $('content')
var res_xml = document.importNode(transport.responseXML.documentElement, true)
content.parentNode.replaceChild(res_xml, content)

You can’t just take plain transport.responseXML object and use replaceChild or appendChild methods on it. You need to call importNode or adoptNode first, to import it to the current document, only after that you can use replaceChild or appendChild.

It took me 2 hours to figure that out, because Safari doesn’t show any error message when you don’t use importNode, it just doesn’t work. And in Firefox it works, but without any error message or a warning, which makes it very difficult to find the error.

Ruby 1.9.1 and Rails

Dennis — Tue, 14 Apr 2009 23:32:31 +0000

I installed ruby 1.9.1 and was gonna upgrade my rails apps to Rails 2.3. These are the problems I ran into during the upgrade.

MySQL Gem

Automatic installation of mysql 2.8.1 gem for ruby 1.9.1 on Mac OS 10.5 doesn’t work. Here is how to install it manually.

1. First thing, check whether you meet requirements on mysql gem’s page.
Note: mysql 2.8.1 gem doesn’t support MySQL < 5.0.67 and 5.1.x family (according to this post).

2. Download it from their page on RubyForge. Unpack it, cd to its root directory. Run these commands.

ruby extconf.rb --with-mysql-config=/usr/local/mysql/bin/mysql_config --with-mysql-dir=/usr/local/mysql
make
sudo make install

Ruby-Debug Gem

Ruby-debug 0.10.3 gem doesn’t support ruby 1.9.x. If you have some important sites in rails, maybe you shouldn’t switch to ruby 1.9.x yet, as debugging will not be available.

UPDATE: Ruby-debug19 is now available for Ruby 1.9.