Routing with an optional parameter

ruby-on-rails routing rails-routing ruby-on-rails-2
Alessandro De Simone picture Alessandro De Simone · Sep 2, 2011 · Viewed 31.8k times · Source

I added in the route file:

map.show_book "/show_book/:name/year/:year", :controller => "book", :action => "show_version"

I also added:

map.show_book "/show_book/:name", :controller => "book", :action => "show_version"

to show the latest book without specifying the year.

But it doesn't work, it cannot find the route in "show_book/NAME" if I don't pass the year.

Do you have some ideas why it doesn't work ?

THANKS !

PS. I know that I can use year as parameter with "?year=XXXX", but I want to use the year as a part of the URL

Answer

Benoit Garret picture Benoit Garret · Sep 2, 2011

Put the optional parts between parenthesis:

map.show_book "/show_book/:name(/year/:year)", :controller => "book", :action => "show_version"

and remove the second route.

Update

The above answer is only for rails 3 and above. Inverting the two routes definitions fixed the problem (see Alessandro's comment below).

Related questions

Rails 3 link_to (:method => :delete) not working

I'm having trouble with my verbs in Rails... viewing a page for a resource (Dog) which has_many (Fleas). Embedded in dog's show.html.haml is a call to render @dog.fleas which automatically(?) finds & uses the template in "…

Read More
Routes with Dash `-` Instead of Underscore `_` in Ruby on Rails

I want my urls to use dash - instead of underscore _ as word separators. For example controller/my-action instead of controller/my_action. I'm surprised about two things: Google et al. continue to distinguish them. That Ruby on Rails doesn't …

Read More
How can I use Rails routes to redirect from one domain to another?

My app used to run on foo.tld but now it runs on bar.tld. Requests will still come in for foo.tld, I want to redirect them to bar.tld. How can I do this in rails routes?

Read More