Scala Play Quickstart

1. Provision Your App

Tell the Aptible API that you want to provision an application. Until you push code and trigger a build, Aptible uses this as a placeholder.

Use the apps:create command: aptible apps:create $APP_HANDLE

For example:

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aptible apps:create play-example

2. Add a Git Remote

Add a Git remote named “aptible”:

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git remote add aptible git@beta.aptible.com:$ENVIRONMENT_HANDLE/$APP_HANDLE.git

For example:

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git remote add aptible git@beta.aptible.com:test-env/play-example.git

3. Add a Dockerfile and a Procfile

A Dockerfile is a text file that contains the commands you would otherwise execute manually to build a Docker image. Aptible uses the resulting image to run your containers.

A Procfile explicitly declares what processes we should run for your app.

A few guidelines:

  1. The files should be named “Procfile” and “Dockerfile”: One word, initial capital letter, no extension.
  2. Place both files in the root of your repository.
  3. Be sure to commit them to version control.

Here is a sample Dockerfile for a conventional Play app:

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# Dockerfile
FROM quay.io/aptible/java:oracle-java8

# Install prerequisite tools
RUN apt-get update && apt-get -y install wget unzip

# Install Scala
RUN cd /usr/share && \
    wget http://www.scala-lang.org/files/archive/scala-2.10.4.tgz && \
    tar xzf scala-2.10.4.tgz && \
    ln -s /usr/share/scala-2.10.4 /usr/share/scala && \
    rm -f /tmp/scala-2.10.4.tgz
ENV PATH $PATH:/usr/share/scale/bin

# Install Activator (omit if not needed)
RUN cd /opt && \
    wget http://downloads.typesafe.com/typesafe-activator/1.2.10/typesafe-activator-1.2.10.zip && \
    unzip typesafe-activator-1.2.10.zip && \
    rm -f /opt/typesafe-activator-1.2.10.zip && \
    mv /opt/activator-1.2.10 /opt/activator
ENV PATH $PATH:/opt/activator

ADD . /app
WORKDIR /app

RUN activator -XX:+UseCodeCacheFlushing clean compile dist

# Change the following command to match your actual app name
RUN cd playexample/target/universal && unzip playexample-1.0-SNAPSHOT.zip

EXPOSE 80

Here is a sample Procfile for a Play app. You will need to update this command to match your actual app name, instead of playexample:

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web: playexample/target/universal/*-SNAPSHOT/bin/playexample \
     -Dhttp.port=$PORT \
     -DapplyEvolutions.default=true \
     -Ddb.default.driver=org.postgresql.Driver \
     -Ddb.default.url=$DATABASE_URL

Alternatively, you can omit the runtime database configuration options and instead use your conf/application.conf file.

4. Provision and Connect a Database

By default, aptible db:create $DB_HANDLE will provision a 10GB PostgreSQL database.

aptible db:create will return a connection string on success. The host value is mapped to a private subnet within your stack and cannot be used to connect from the outside Internet. Your containerized app can connect, however.

Add the database connection string to your app as an environment variable:

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aptible config:set DATABASE_URL=$CONNECTION_STRING

To connect locally, see the aptible db:tunnel command.

5. Deploy Your App

Make sure your code is committed, then push to the master branch of the Aptible Git remote:

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git push aptible master

Deploy logs will stream to your terminal.

6. Add an Endpoint

To expose your app to the Internet, you’ll want to add an HTTPS Endpoint. In the Aptible dashboard, select your app, then open the “Endpoints” tab.

  1. Service: Select the app service you want to expose (often a web service).
  2. Endpoint type: The quickest option is request a default *.on-aptible.com endpoint address, which will serve the *.on-aptible.com wildcard certificate. With a custom endpoint, you provide a certificate and key for a domain of your choice.
  3. Type: External endpoints are exposed to the Internet, meaning their endpoint addresses resolve to public IP addresses. Internal endpoints receive private IP addresses and are only routable from within your stack.
  4. Save the endpoint, wait for it to provision (usually 2-15 minutes), then test the endpoint address. To test internal endpoints, you can aptible ssh into your app to spin up an ephemeral container, then curl your internal endpoint.

On each subsequent deploy, the Aptible platform will perform a health check on any service with an endpoint. For HTTPS Endpoints, the health check involves making an HTTP request and listening for any response. The service is considered healthy if it responds, regardless of the response status code. Deploys that fail their health checks will not be released.

This guide requires that you have:

  • An Aptible account
  • An SSH key associated with your Aptible user account
  • The Aptible Toolbelt installed