How to get url parameters from rails

Hi Folks,

I have this path configured in my html.rb file:

<td><%= link_to traces_by_original_exchange.short_exchange_id,
list_trace_by_short_exchange_id_path(traces_by_original_exchange.short_exchange_id)
%></td>

and this in my route.rg file

match 'esb/list_trace_by_short_exchanges' =>
'esb#list_trace_by_short_exchanges', :as =>
:list_trace_by_short_exchange_id

the link above generates a path:

http://localhost:3000/esb/list_trace_by_short_exchanges.ID-swordfish-27243-1327514975752-13-85879

However in my controller:
I need to be able to retrieve
"ID-swordfish-27243-1327514975752-13-85879"

I have the listing below (in my controller):

def list_trace_by_short_exchanges
@traces_by_short_exchanges = TblTrace.find_by_sql("select top (1) * from
tbl_traces
  where short_exchange_id = '" + params[:id] + "' order by created_on
desc")

respond_to do |format|
  format.html # show.html.erb
  format.json { render :json => params[:id] }
end
end

How do I retrieve that value?

Note that I had tried:

<td><%= link_to traces_by_original_exchange.short_exchange_id,
traces_by_original_exchange.short_exchange_id %></td>

but the url turns out to be

http://localhost:3000/esb/ID-swordfish-27243-1327514975752-13-85879

but I need the url to be:

http://localhost:3000/esb/list_trace_by_short_exchanges/ID-swordfish-27243-1327514975752-13-85879

or atleast get that parameter:

ID-swordfish-27243-1327514975752-13-85879

in the function list_trace_by_short_exchanges in ym controller.

What is the best way to do this?

given: @url = "http://localhost:3000/esb/ID-
swordfish-27243-1327514975752-13-85879"
         @searchPattern = /(ID-swordfish-(\d+-)(\d+-)(\d+-)(\d+))/
with: Ruby 1.9.2 or greater
when: @searchPattern =~ @url
then: $1 = "ID-swordfish-27243-1327514975752-13-85879"

Individual results may vary!

Cheers,

SC