Java

A Maven or Gradle project deploys from its repository with no Dockerfile. Nimbus Land recognises pom.xml, build.gradle and build.gradle.kts, builds the project and starts it. Spring Boot is recognised too.

Quick start#

In the console, create an app from your repository with the deploy wizard. From the CLI, run this in the project directory:

nimbus deploy

Make your server listen on PORT. See what every app needs.

Spring Boot#

Set the port in application.properties:

server.port=${PORT:8080}

When the plan can't tell what will run#

If the deploy plan can't tell what will run, add a Procfile with a web: line that starts your server on $PORT.

Scala#

Scala projects (build.sbt) are built too. As with Java, make the server listen on PORT, and add a Procfile if the plan can't tell what will run.

Troubleshooting#

For problems that aren't specific to Java, such as an app that never answers, see Apps troubleshooting.

The app builds but never answers#

The server is listening on a fixed port. Read PORT, as shown under Spring Boot, or add a Procfile with a web: line that passes it.

Database certificate errors#

Attaching Postgres sets DATABASE_CA_CERT. JDBC connects in prefer mode by default, which works as is. To verify the certificate, write DATABASE_CA_CERT to a file at start-up and use sslmode=verify-full sslrootcert=<path>.