Flyway Heroku Demo

The Spring Boot model of deploying standalone applications is a great fit for Heroku. You can use either Maven or Gradle to deploy a Spring application on Heroku, but for this guide we’ll assume that you’re using Maven and have Maven 3 installed on your machine.

To begin, create a free Heroku account. Then download and install the Heroku CLI.

DOWNLOAD HEROKU CLI

Once installed, you can use the heroku command from the terminal to log in using the email address and password you used when creating your Heroku account:

heroku login

Preparing a Spring Boot app for Heroku

git clone https://github.com/joaopbini/flyway-heroku-demo.git

cd flyway-heroku-demo

heroku create

This also creates a remote repository called heroku in your local git repo. Heroku generates a random name for your app. You can rename it later with the heroku apps:rename command.

Now deploy your code:

git push heroku master

The application is now deployed. You can visit the app’s URL by running this command:

heroku open

Access your application url heroku /swagger-ui.html (in my case: https://flyway-heroku-demo.herokuapp.com/swagger-ui.html) to see the api documentation and execute the endpoint /person to see:

[
  {
    "firstName": "Dave",
    "lastName": "Syer"
  },
  {
    "firstName": "Joao",
    "lastName": "Bini"
  }
]

You can view the logs for the application by running this command:

heroku logs --tail

Extra: Some Variables

You can see the DATABASE_URL provided to an application by running:

heroku config

The official Heroku buildpacks for Java, Kotlin, Scala, Clojure, and Gradle will attempt to create a JDBC_DATABASE_URL environment variable when a dyno starts up. This variable is dynamic and will not appear in your list of configuration variables when running heroku config. You can view it by running the following command:

heroku run echo $JDBC_DATABASE_URL

The variable will include ?user=<user>&password=<password> parameters, but JDBC_DATABASE_USERNAME and JDBC_DATABASE_PASSWORD environment variables will also be set when possible.

More Information

https://devcenter.heroku.com/articles/deploying-spring-boot-apps-to-heroku

https://devcenter.heroku.com/articles/connecting-to-relational-databases-on-heroku-with-java

https://devcenter.heroku.com/articles/procfile

How to run locally

mvn clean install

mvn spring-boot:run

Access http://localhost:8080/swagger-ui.html