Building [Play Framework apps with Scala][1] is all the rage right now. And for good reason... It's never been easier to build and deploy JVM-based web apps! Lets walk through how to build a Play app with Scala and then deploy it on the cloud with Heroku.

Step 1) [Install the Play Framework][2] (make sure you have at least version 1.2.3)

Step 2) Install the Play Scala module:

```bash
play install scala
```

Step 3) Create a new Play app with Scala support:

```bash
play new playwithscala --with scala
```

Step 4) Start the app:

```bash
cd playwithscala
play run
```

Step 5) Open the app in your browser:
  
<http://localhost:9000>

That was easy! Lets spice this up a bit before we deploy it on Heroku by adding a custom model, view, and controller.

Step 1) Create a new _app/models/Widget.scala_ file containing:

```scala
package models

case class Widget(id: Int, name: String)
```

Step 2) Create a new _app/views/Widget/list.scala.html_ file containing:

```scala
@(widgets: Vector[models.Widget])



    
        @widgets.map { widget => 
            Widget @widget.id = @widget.name</br>
        }
    

```

Step 3) Create a new _app/controllers/WidgetController.scala_ file containing:

```scala
package controllers

import play._
import play.mvc._

object WidgetController extends Controller {

    import views.Widget._
    import models.Widget

    def list = {
        val widget1 = Widget(1, "The first Widget")
        val widget2 = Widget(2, "A really special Widget")
        val widget3 = Widget(3, "Just another Widget")
        html.list(Vector(widget1, widget2, widget3))
    }

}
```

Step 4) Test out the new code by going to:
  
<http://localhost:9000/WidgetController/list>

It works! And we didn't even need to reload the server! But lets clean up that URL a bit. Edit the _conf/routes_ file and change "Application.index" to "WidgetController.list":

```
GET     /                                       WidgetController.list
```

Now load the new URL:
  
[http://localhost:9000/][3]

That was easy but now we want to show our friends. So lets deploy it on Heroku.

Step 1) Install the Heroku command line client on [Linux][4], [Mac][5], or [Windows][6]

Step 2) Login to Heroku from the command line:

```bash
heroku auth:login
```

Step 3) Heroku uses git for application upload, so create a .gitignore file containing:

```
/modules
/tmp
```

Step 4) Create a git repo, add the files to it, and commit them:

```bash
git init
git add .
git commit -m init
```

Step 5) Create the new application on Heroku:

```bash
heroku create -s cedar
```

This provisions a new application on Heroku and assigns a random name / URL to the app.

Step 6) Deploy the application:

```bash
git push heroku master
```

The application will now be assembled and deployed on Heroku.

Step 7) Open the application in the browser:

```bash
heroku open
```

Tada! Your Play + Scala app is now running on the cloud!

At JavaOne I showed this to Bill Venners (creator of [ScalaTest][7]). He then moved the scalatest.org website (a Play + Scala app) to Heroku! Cool stuff!

Let me know if you have any questions.

 [1]: http://scala.playframework.org/
 [2]: http://www.playframework.org/download
 [3]: http://localhost:9000/widgets/list
 [4]: http://toolbelt.herokuapp.com/linux/readme
 [5]: http://toolbelt.herokuapp.com/osx/download
 [6]: http://toolbelt.herokuapp.com/windows/download
 [7]: http://www.scalatest.org/