RESTfulLoc.scala

/**
 *  A RESTful-like URL handling Loc
 *
 *  If you have the following templates:
 *
 *    * webapps/item/edit.html
 *    * webapps/item/view.html
 *  
 *  You want the following URL map to corresponding template with 
 *  last path component as a S parameter.
 *
 *    http://localhost/item/edit/1  to  http://localhost/item/edit
 *    http://localhost/item/view/1  to  http://localhost/item/view
 *
 *  You could create a Menu with this Loc class in your Model object.
 *
 *  <code>
 *  object Item extends Item with LongKeyedMetaMapper[Item] 
 *  {
 *      // Other methods here...
 *
 *      def menu () {  
 *
 *          // What methods do we have?
 *          val methods = List ("view", "edit")
 *
 *          val parameterName = "itemID"
 *          val itemLoc = new RESTfulLoc("Item", List("item"), "Item", 
 *                                       methods, parameterName)
 *
 *          Menu (itemLoc)
 *      }
 *  }
 *  </code>
 *
 *  Now add the menu to SiteMap in Boot.boot
 *
 *  <code>
 *  class Boot {
 *      def boot () {
 *          
 *          val entries = Item.menu ::  Nil
 *
 *          LiftRules.setSiteMap(SiteMap(entries:_*))
 *      }
 *  }
 *  </code>
 *
 *
 *  Finally, You could access the parameter in your snippet with 
 *  S.param("itemID")
 *
 */
class RESTfulLoc (val name: String, val path: List[String],
                  val text: LinkText[Unit], val methods: List[String],
                  val parameterName: String,
                  val locParams: LocParam[Unit]*) extends Loc[Unit] 
{
    override val defaultValue = Full(())
    override val params = locParams.toList
    override val link: Link[Unit] = (List(path.first), true)

    def this (name: String, path: List[String], text: LinkText[Unit], 
              methods: List[String], locParams: LocParam[Unit]*) = 
    {
        this (name, path, text, methods, "id", locParams:_*)
    }

    private def isTarget (path: ParsePath) = 
    {
        path.partPath -- this.path match {
            case List (action, id) => {
                (methods contains action) && id != "index"
            }
            case _ => false
        }
    }

    override def rewrite = Full (NamedPF("RESTfulLoc") 
    {
        case RewriteRequest (path, _, _) if isTarget(path) => {
             val parameter = path.partPath.last
             val action    = path.partPath.init
             val data      = Map (parameterName -> parameter)
             
             RewriteResponse(action, data) -> ()
        }
    })
}