CRUD operations using Scalatra and Casbah

Question

I'm learning Scala and MongoDB and such am using Scalatra and Casbah as the framework for a simple web app.

It is a simple message board, the intention to learn CRUD operations in Casbah. Problems is I'm finding that when I list the messages I have no way to uniquely reference a record in MongoDB on the site.

My current code is below.

The issue I'm having is that a ObjectID cannot be cast into a string. But without a unique id for each row I cannot provide a delete function from the web page.

Is there a standard way of handling these things using Casbah? All the tutorials I've seen have ignored uniquely accessing records from a webpage or completely ignored scalatra and focused only on handling records from scala code.

indexController.scala

get("/msgs") 
{
    contentType = "text/html";
    var list = new ListBuffer[Message]()

    for (i <- coll.find())
    {
        var message = new Message();
        message.author = i.getOrElse("author", "???").toString();
        message.message = i.getOrElse("msg", "???").toString();
        message.id = i.getOrElse("_id", "???").asInstanceOf[String];

        list += message;
    }

    layoutTemplate("/Views/index.scaml",("list" -> list.toList));
}

index.scaml

%body
    %h2
    Messages
    %br
        %ul
            -@ val list: List[domain.Message]
            - for (l:domain.Message <- list)
                %li
                    From: #{l.author}
                    \- #{l.message}
                    %form{:method => "DELETE", :action => "msg/#{l.id}"}
                        %input{:type => "submit", :value => "Delete"}

Answer 1

You cannot cast but you can render it as a String easilly after:

i.getAs[ObjectId]("_id") map (_.toString) getOrElse "???"

And in the template you could do this

#{l.id.toString}