Question

I am trying to parse URLs. For example where I am trying to pull out:

~/locations/1 => [locations,1]
~/locations/1/comments => [locations,1]
~/locations/1/comments/22 => [locations,1]
~/locations/1/buildings/3 => [buildings,3]
~/locations/1/buildings/3/comments => [buildings,3]
~/locations/1/buildings/3/comments/34 => [buildings,3]

The format is pretty consistent. I started with arrays but it seems to still fail:

@request_path = request.path.downcase.split('/')
@comment_index = @request_path.index("comments").to_i
if @comment_index > 0
  @request_path = @request_path.drop_while { |i| i.to_i >= @comment_index }
end
resource, id = @request_path.last(2)

I added the downcase just incase someone manually typed in an uppercase URL. The drop_while seems to not be working.

Answer 1

What kind of output you have after processing your code?

Edited

Your problem is that you convert element to_i and it is 0. But you want to compare index of element, but can normally get index of element in that situation using Array#index method.

Correct approach:

@request_path.drop_while { |i| @request_path.index(i) >= @comment_index }

You can parse path without drop_while.

My solution:

def resource_details(path)
    resource_array = path.downcase.split("/").reject!(&:empty?)
    key = resource_array.index("comments")
    return key.present? ? (resource_array - resource_array[key..key + 1]).last(2) : resource_array.last(2)
 end

It will cut out ["comments"] or ["comments","2"] for your path.

Invoke that method:

1.9.3p0 :051 > resource_details("/locations/1/buildings/3/comments")
 => ["buildings", "3"] 

1.9.3p0 :052 > resource_details("/locations/1/comments/2")
 => ["locations", "1"]