Open Liberty Getting Started sample

Overview

The sample application provides a simple example of how to get started with Open Liberty. It provides a REST API that retrieves the system properties in the JVM and a web based UI for viewing them. It also uses MicroProfile Config, MicroProfile Health and MicroProfile Metrics to demonstrate how to use these specifications in an application that maybe deployed to kubernetes.

Project structure

• src/main/java - the Java code for the Project
  • io/openliberty/sample
    • config
      • ConfigResource.java - A REST Resource that exposes MicroProfile Config via a /rest/config GET request
      • CustomConfigSource.java - A MicroProfile Config ConfigSource that reads a json file.
    • system
      • SystemConfig.java - A CDI bean that will report if the application is in maintenance. This supports the config variable changing dynamically via an update to a json file.
      • SystemHealth.java - A MicroProfile Health check that reports DOWN if the application is in maintenance and UP otherwise.
      • SystemResource.java - A REST Resource that exposes the System properties via a /rest/properties GET request. Calls to this GET method have MicroProfile Timer and Count metrics applied.
      • SystemRuntime.java - A REST Resource that exposes the version of the Open Liberty runtime via a /rest/runtime GET request.
    • SystemApplication.java - The Jakarta RESTful Web Services Application class
  • liberty/config/server.xml - The server configuration for the liberty runtime
  • META-INF - Contains the metadata files for MicroProfile Config including how to load CustomConfigSource.java
  • webapp - Contains the Web UI for the application.
  • test/java/it/io/openliberty/sample/health
    • HealthIT.java - Test cases for a sample application running on localhost
    • HealthUtilIT.java - Utility methods for functional tests
• resources/CustomConfigSource.json - Contains the data that is read by the MicroProfile Config ConfigSource.
• Dockerfile - The Dockerfile for building the sample
• pom.xml - The Maven POM file

Build and Run the Sample locally

Clone the project

git clone https://github.com/OpenLiberty/sample-getting-started.git

then build and run it using Liberty dev mode:

mvnw liberty:dev

if you just want to build it run:

mvnw package

Run the Sample in a container

To run the sample using docker run:

docker run -p 9080:9080 icr.io/appcafe/open-liberty/samples/getting-started

To run the sample using podman run:

podman run -p 9080:9080 icr.io/appcafe/open-liberty/samples/getting-started

Access the application

Open a browser to http://localhost:9080

Run the functional tests

The test cases uses JUnit 5 and Maven Failsafe Plugin defined in pom.xml.

Note: Sample appplication must be running on http://localhost before running the test cases.
See HealthUtilIT.java to change the change the sample application target URL.

To run the test cases against a running sample application, use the following command

mvnw failsafe:integration-test

To view the test results, look at the console output or look under directory target/failsafe-reports