I've been working on a [Play 2 application][1] that I'll be using for the [Grails vs Play Smackdown][2] at ÜberConf next week. The app is running in production on [Heroku][3] but since I don't have an admin UI yet, I needed a quick and easy way to create a new entity. I could have gone straight to the database but thought it would be better to run Play 2's Scala Console on Heroku and then just run some arbitrary Scala code. The Scala Console in Play 2 is really just the Scala REPL in SBT but it allows you to interact with a Play application.

I'll walk you through how to use the Play 2 Scala Console on Heroku. If you'd like to follow along, grab the [play2bars][4] app by running:

```bash
git clone https://github.com/jamesward/play2bars.git
cd play2bars
git checkout java-ebean
```

To run the console locally, run:

```bash
play -DapplyEvolutions.default=true console
```

You will see something like:

```bash
[info] Loading project definition from /home/jamesw/Desktop/play2bars/project
[info] Set current project to play2bars-java (in build file:/home/jamesw/Desktop/play2bars/)
[info] Updating {file:/home/jamesw/Desktop/play2bars/}play2bars-java...
[info] Resolving org.hibernate.javax.persistence#hibernate-jpa-2.0-api;1.0.1.Fin                                                                                [info] Done updating.                                                        
[info] Compiling 4 Scala sources and 3 Java sources to /home/jamesw/Desktop/play2bars/target/scala-2.9.1/classes...
[warn] Note: /home/jamesw/Desktop/play2bars/app/models/Bar.java uses unchecked or unsafe operations.
[warn] Note: Recompile with -Xlint:unchecked for details.
[info] Starting scala interpreter...
[info] 
Welcome to Scala version 2.9.1.final (OpenJDK 64-Bit Server VM, Java 1.7.0_03).
Type in expressions to have them evaluated.
Type :help for more information.

scala> 
```

Start a Play app from the Scala console:

```scala
new play.core.StaticApplication(new java.io.File("."))
```

You will see something like:

```
[info] play - database [default] connected at jdbc:h2:mem:play
[info] play - Application started (Prod)
res0: play.core.StaticApplication = play.core.StaticApplication@2e338c56
```

Now you can interact with the Play application. Lets create a new "Bar" entity:

```scala
var bar = new models.Bar()
bar.name = "foo bar"
bar.save
```

And now you can query the "Bar" entities:

```scala
import scala.collection.JavaConversions._
models.Bar.find.all.foreach(bar => println(bar.name))
```

So that's pretty cool, right?

If you want to run this example on Heroku, then install the [Heroku Toolbelt][5] and run:

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

And push the application to Heroku:

```bash
git push heroku java-ebean:master
```

Once the application is built and deployed on Heroku, check to make sure it works:

```bash
heroku open
```

To run the Scala console on Heroku, run:

```bash
heroku run bash
java -DapplyEvolutions.default=true -Ddb.default.driver=org.postgresql.Driver -Ddb.default.url=$DATABASE_URL -jar ~/.sbt_home/bin/sbt-launch-0.11.3-2.jar
```

SBT will resolve some dependencies and then you will be in the SBT console. From there run:

```scala
set fullClasspath in Compile += Attributed.blank(file("target/staged/*"))
console
```

Now you will be in the Scala REPL for your Play app on Heroku. So you can run things like:

```scala
new play.core.StaticApplication(new java.io.File("."))
var bar = new models.Bar()
bar.name = "foo bar"
bar.save
```

Reload your app on Heroku in the browser and you should now see the new Bar listed on the page!

Let me know if you have any questions.

 [1]: https://github.com/jamesward/happytrails/tree/play2_java
 [2]: http://uberconf.com/conference/denver/2012/06/session?id=25584
 [3]: http://heroku.com
 [4]: https://github.com/jamesward/play2bars
 [5]: http://toolbelt.heroku.com