Blog of Aaron Theodore

Sometimes it is nice to be able to show meaningful text in your URLs

URLs like: http://www.site.com/sports/1/teams/1;results
Although relatively short, don't have a lot of meaning

http://www.site.com/sports/cricket/teams/first-11;results
Has more meaning, but is not ideal from the web applications point of view.

http://www.site.com/sports/1-cricket/teams/1-first-11;results
Is the best of both worlds, and surprisingly easy to achieve in ruby.

In all the models you want a descriptive id, just overwrite the to_params method. By default model.to_params returns the value of the models primary key.

In my case the name field of all my models is the field i want to appear in the URL.

The following will do that. Sets the name to lowercase and replaces spaces with -

 
  def to_param
    "#{id}-#{name.downcase.gsub(/ /, '-'))}"
  end

Unfortunately this is not ideal, what if you had non ascii characters in your name, you would end up with escaped characters and an ugly URL

So i chose to make use of the PermalinkFu plugin from Rick Olson

 
  def to_param
    "#{id}-#{PermalinkFu.escape(name)}"
  end

The PermalinkFu plugin will convert the string so it is suitable to be placed in the url, it uses Iconv to do a unicode translation to ascii. This means strings such as café get translated to cafe

You might think that by overwriting to_params rails would get confused, but it dosn't. Well as long as you observe a simple rule:

• When generating a url pass the model in where it expects an id
  :id => model NOT :id => model.id This works as rails automatically calls to_params to get the id, if you call model.id it will bypass to_params

After writing this i noticed SEO on Rails posted about Even better looking URLs with permalink_fu. I don’t think this is ideal since if you update the name/permalink anyone linking to your URLs will end up with a broken link. Also there is no way to ensure unique permalinks (unless you add extra code into your model which i will cover in a future post).