Installing Feedzirra RSS Parser on Ubuntu 8

I recently watched a RailsCasts episode (http://railscasts.com/episodes/168-feed-parsing) on parsing and persisting RSS feeds using Feedzirra. It took a little setting up on Ubuntu because it relies on some libraries that aren’t included with Ubuntu > 8.

The gem will fail right off the bat

gem sources -a http://gems.github.com # if you haven't already
gem install pauldix-feedzirra

Here is what I needed before I could install the gem

apt-get install libcurl3
apt-get install libxml2 libxml2-dev
apt-get install libxslt1-dev

Then go ahead and

gem install pauldix-feedzirra

Here are some other useful resources

http://github.com/pauldix/feedzirra/tree/master

http://ruby.zigzo.com/2009/02/15/feedzirra-installation-errors/

Email Obfuscation and Extraction from Text with Rails

There is a helper method for handling the obfuscation of email addresses in Rails.

mail_to "me@domain.com", "My email", :encode => "hex"
 # => <a href="mailto:%6d%65@%64%6f%6d%61%69%6e.%63%6f%6d">My email</a>

If you want to then extract an email address(or all email addresses) from a block of text here is the code. I created a helper function called “emailitize” and put it in the ApplicationHelper module inside helpers/application_helper.rb

module ApplicationHelper
  #takes a string and will return the same string but with email addresses encoded and hyperlinked
  def emailitize(text)
    text.gsub(/([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})/i) {|m|
        mail_to(m, m.gsub("@", "<small>[at]</small>"), :encode=>:hex)
    }
  end
end

It’s important to remember that you’ll need to pass a block to the gsub method. You can’t do something like this instead

text.gsub( /([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})/i, mail_to('\\1@\\2', '\\1@\\2', :encode=>:hex) )

It will work except the encode will fail. It will evaluate the ‘\\1@\\2′ strings rather than as dynamic variables.

You can then use this function in your views

<%= emailitize @job.how_to_apply %>

More information is available in the Rails and Ruby docs:

http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#M001887

http://ruby-doc.org/core/classes/String.html#M000817