Rails - Mar 2006 - Generic ''save'' function for multiple objects?

I''ve been working with developing a few rails/mysql applications to 
replace some rather shoddy access databases that are currently in use 
here.

It''s going well but I ran into one area that I''m curious if
there is a
way to improve.  Basically the database has several instances of 
Many-to-Many relationships to handle different things.

At present each of these has a seperate "add" function that looks like
this:

------------
  def add_entry
    @entry = Entry.new(params[:entry])
    @entry.item_id = params[:id]
    if @entry.save
      flash[:notice] = "Record updated."
      redirect_to :action => "show", :id => params[:id]
    else
      flash[:notice] = "Error: failed to add entry!"
      redirect_to :action => "show", :id => params[:id]
    end
  end
end
------------
Each is virtually identical except one is using say an entry object and 
the next is using a post object.  Is there a way to just build a more 
generic function that would take over this process so I could just pass 
it and item and it would take care of saving it properly?  Is it worth 
bothering with?

The Agile web development book stresses not repeating the same code over 
and over and I''m up to 3 instances of this same basic function,
I''m not
sure there is a way to avoid it and it''s not that big of a deal.  I did
a bit of searching and really couldn''t find something that addressed 
this.

Kevin Kolk

-- 
Posted via http://www.ruby-forum.com/.

Kevin Kolk wrote:
> ------------
>   def add_entry
>     @entry = Entry.new(params[:entry])
>     @entry.item_id = params[:id]
>     if @entry.save
>       flash[:notice] = "Record updated."
>       redirect_to :action => "show", :id => params[:id]
>     else
>       flash[:notice] = "Error: failed to add entry!"
>       redirect_to :action => "show", :id => params[:id]
>     end
>   end
> end
> ------------
> Each is virtually identical except one is using say an entry object and 
> the next is using a post object.  Is there a way to just build a more 
> generic function that would take over this process so I could just pass 
> it and item and it would take care of saving it properly?  Is it worth 
> bothering with?
I''ve got a very similar situation where I''ve been just
copy/pasting, as
you have been, but seeing your question laid out so cleanly makes me 
think of a possible solution.  This ought to be handle-able by passing 
in the actual class of which a new instance is needed.  Everything in 
Ruby is an object, right?  So I am going to try something like this:

   def add_item( type, symbol )
     @item = type.new(params[symbol])
     if @item.save
       // do the things
     end
   end

and call it like this:

   add_item( Entry.class, :entry )

and see what happens.  I don''t know if things work this way in Ruby and
I don''t have time to play with this project again until tomorrow, alas,
so I might be completely wrong here.

Rachel