Deploy Play Framework 2

Overview

Clever Cloud supports Play! 2 applications natively. The following guide explains how to set up your application to run on Clever Cloud.

Play is an open source web application framework, written in Scala and Java, which follows the model–view–controller (MVC) architectural pattern. It aims at optimizing developer productivity by using convention over configuration, hot code reloading and display of errors in the browser.

Create an application on Clever Cloud

via the web console

Refer to our getting started for more details on application creation via the console.

via the Clever Tools CLI

1. Make sure you have clever-tools installed locally or follow our CLI getting started guide.
2. In your code folder, do clever create --type <type> <app-name> --region <zone> --org <org> where :
   1. type is the type of technology you rely on
   2. app-name the name you want for your application,
   3. zone deployment zone (par for Paris and mtl for Montreal)
   4. org the organization ID the application will be created under.

Refer to clever create for more details on application creation with Clever Tools.

Setting up environment variables on Clever Cloud

With the Clever Cloud console

1. Go to the Clever Cloud console, and find the app you want to fine tune under it’s organization.
2. Find the Environment variables menu and select it.
3. In this menu, you will see a form with VARIABLE_NAME and variable value fields.
4. Fill them with the desired values then select Add.
5. Don’t forget to “Update Changes” at the end of the menu.

With the Clever Tools CLI

1. Make sure you have clever-tools installed locally. Refer to our CLI getting started.
2. In your code folder, do clever env set <variable-name> <variable-value>

Refer to environment variables reference for more details on available environment variables on Clever Cloud.

You can of course create custom ones with the interface we just demonstrated, they will be available for your application.

Configure your Java + Playframework 2 application

Mandatory configuration

• The application must be located at the root of the git repository.
• Starting from Play 2.4, your application needs Java 8 to run. Please read Available Java Versions.
• Your Java application needs to listen on 0.0.0.0:8080

Configuration file

You can configure your application start command by adding a ./clevercloud/sbt.json file with the following fields:

{
  "deploy":{
    "goal": "yourgoal"
  }
}

You can use the following properties:

Available Java versions

Simply set the environment variable CC_JAVA_VERSION to the version you want.

Accepted values are 7, 8, 11, 17 or graalvm-ce (for GraalVM 21.0.0.2, based on OpenJDK 11.0).

We follow the official Java roadmap by supporting both LTS and latest non-LTS versions.

We are using OpenJDK distribution for mentionned Java versions.

HTTPS support

HTTPS is handled by Clever Cloud ahead of your application, your application retrieves the traffic in plain http. To be able to use request.secure, you have to add trustxforwarded=true in application.conf.

Known problems with Play! 2

Please read the following if your project fails with this error:

sbt.ResolveException: unresolved dependency: play#sbt-plugin;2.0: not found

Some versions of Play2 try to retrieve a nonexistent version of “sbt-plugin” which is required by the framework to work. You have two options to fix this problem:

You can set the “play.version” environment variable in the clevercloud/sbt.json file. For example, for Play 2.0.4:

{
  "deploy": {
    "goal": "-Dplay.version=2.0.4"
  }
}

Otherwise, you can modify plugins.sbt in the project folder of your app like the following:

// Comment to get more information during initialization
logLevel := Level.Warn

// The Typesafe repository
resolvers += "Typesafe repository" at "https://repo.typesafe.com/typesafe/releases/"

// Use the Play sbt plugin for Play projects
addSbtPlugin("play" % "sbt-plugin" % "2.0.4") // The important part of the configuration

The two solutions do the job, you can pick your favorite.

Environment injection

Clever Cloud injects environment variables from your application settings as mentioned in setting up environment variables and is also injecting in your application production environment, those from your linked add-ons.

To access environment variables from your code, you need to reference them in your application.conf file with my.option=${MY_VARIABLE} and then use the configuration item my.option in your application.

You can also use the System.getenv("MY_VARIABLE") method. Be aware that it can return null.

Monitor your application with New Relic

You can use New Relic to monitor your application on Clever Cloud.

Please refer to our New Relic documentation to configure it for your application.

Git Deployment on Clever Cloud

You need Git on your computer to deploy via this tool. Here is the official website of Git to get more information: git-scm.com

Setting up your remotes

1. The “Information” page of your app gives you your Git deployment URL, it looks like this:

   1. git+ssh://[email protected]/<your_app_id>.git
   2. Copy it in your clipboard

2. Locally, under your code folder, type in git init to set up a new git repository or skip this step if you already have one

3. Add the deploy URL with git remote add <name> <your-git-deployment-url>

4. Add your files via git add <files path> and commit them via git commit -m <your commit message>

5. Now push your application on Clever Cloud with git push <name> master

Refer to git deployments for more details.

Linking a database or any other add-on to your application

By linking an application to an add-on, the application has the add-on environment variables in its own environment by default.

On add-on creation

Many add-ons do exist on Clever Cloud, please refer to the full list and check add-ons dedicated pages for full instructions.

During add-on creation, you will see Applications screen, with a list of your applications. You can toggle the button to Link and click next. If you finish the process of add-on creation, the application will automatically be linked to it.

Add-on already exists

In the Clever Cloud console, under the Service Dependencies menu of your application, you can use the Link addons dropdown menu to select the name of the add-on you want to link and use the add button to finish the process.

You can also link another application from the same page in the Clever Cloud console, using the Link applications dropdown menu.

More configuration

Need more configuration? To run a script at the end of your deployment? To add your private SSH key to access private dependencies?

Go check the Common configuration page.

You may want to have an advanced usage of your application, in which case we recommend you to read the Administrate documentation section.

If you can’t find something or have a specific need like using a non supported version of a particular software, please reach out to the support.