AusNimbus Builder for Java

The AusNimbus builder for Java provides a fast, secure and reliable Java hosting environment.

This document describes the behaviour and environment configuration when running your Java apps on AusNimbus.

• Runtime Environments
• Web Process
• Dependency Management
• Environment Configuration
• Extending
  • Build Stage (assemble)
  • Runtime Stage (run)
  • Persistent Environment Variables
• Debug Mode

Runtime Environments

AusNimbus supports the latest stable Java release.

Maven is used to build your application and OpenJDK is used to run it.

The most recent version of Maven will be used unless a Maven wrapper is found. To use the Maven wrapper you need to include the mvnw file and .mvn directory in your repository.

The currently supported versions are jdk8

Web Process

Your application's web processes must bind to port 8080.

AusNimbus handles SSL termination at the load balancer.

Dependency Management

You are able to pass your own parameters to maven during the build stage by using the following environment variable:

NAME	Description
MAVEN_CUSTOM_OPTS	Parameters passed to the Maven build process. Default: -DskipTests
MAVEN_CUSTOM_GOALS	Parameters passed to the Maven build process. Default: clean dependency:list install

Environment Configuration

The following environment variables are available for you to configure your Java environment:

NAME	Description
MAVEN_JAVA_OPTS	Options passed to Java. (Default: -Xmx$((MEMORY_LIMIT * 90 / 100))m)

By default the builder will look for settings.xml in the root repository. You can use either of the following environment variables to specify alternate file locations

NAME	Description
MAVEN_SETTINGS_PATH	Define the specific file path for the settings.xml
MAVEN_SETTINGS_URL	Define a URL where the settings.xml can be downloaded from

Extending

AusNimbus builders are split into two stages:

• Build
• Runtime

Both stages are completely extensible, allowing you to customize or completely overwrite each stage.

Build Stage (assemble)

If you want to customize the build stage, you need to add the executable .s2i/bin/assemble file in your repository.

This file should contain the logic required to build and install any dependencies your application requires.

If you only want to extend the build stage, you may use this example:

#!/bin/bash

echo "Logic to include before"

# Run the default builder logic
. /usr/libexec/s2i/assemble

echo "Logic to include after"

Runtime Stage (run)

If you only want to change the executed command for the run stage you may the following environment variable.

NAME	Description
APP_RUN	Define a custom command to start your application.

NOTE: APP_RUN will overwrite any builder's runtime configuration (including the Debug Mode section)

Alternatively you may customize or overwrite the entire runtime stage by including the executable file .s2i/bin/run

This file should contain the logic required to execute your application.

If you only want to extend the run stage, you may use this example:

#!/bin/bash

echo "Logic to include before"

# Run the default builder logic
. /usr/libexec/s2i/run

As the run script executes every time your application is deployed, scaled or restarted it's recommended to keep avoid including complex logic which may delay the start-up process of your application.

Persistent Environment Variables

The recommend approach is to set your environment variables in the AusNimbus dashboard.

However it is possible to store environment variables in code using the .s2i/environment file.

The file expects a key=value format eg.

KEY=VALUE
FOO=BAR

Debug Mode

The AusNimbus builder provides a convenient environment variable to help you debug your application.

NAME	Description
DEBUG	Set to "TRUE" to enable Debug Mode

Web processes must bind to port 8080 and only the HTTP protocol is permitted for incoming connections.