How to Overwrite variables to Payara JPA access Upsun.sh SQL services

Matt Sinagra

Updated March 12, 2026 05:26

Goal

In this tutorial, we’ll cover how you can overwrite Payara configurations to access the services in Upsun.

Preparation

This tutorial assumes you have

A working Payara application with Java 8 or higher
A text editor of your choice.

Problems

Upsun has a Java configuration-reader library that provides a streamlined and easy to use way to interact with a Upsun environment and those services. However, you can also use the application regularly and overwrite those configurations when you deploy your application on Upsun. That is useful when you either already have one app and want to move to Upsun or keep the default configuration to run locally.

Steps

First, to use a database as a data source in Payara Micro, you’ll need to have the database already running. Once you have that in place, download the JDBC driver for the database and put it into your WEB-INF/lib directory.

In your web.xml add the following:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="4.0" xmlns="http://xmlns.jcp.org/xml/ns/javaee"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd">
    <data-source>
        <name>java:global/JPAExampleDataSource</name>
        <class-name>org.postgresql.ds.PGSimpleDataSource</class-name>
        <server-name>${server.host}</server-name>
        <port-number>5432</port-number>
        <database-name>${server.database}</database-name>
        <user>${server.user}</user>
        <password>${server.password}</password>
    </data-source>
</web-app>

You can overwrite those configurations on the upsun.app.yaml the application configuration to Upsun. As shown in the configuration below.

name: app
type: "java:8"
disk: 1024
hooks:
    build: mvn clean package payara-micro:bundle
relationships:
    database: "db:postgresql"
web:
    commands:
        start: |
          export HOST=`echo $PLATFORM_RELATIONSHIPS|base64 -d|jq -r ".database[0].host"`
          export PASSWORD=`echo $PLATFORM_RELATIONSHIPS|base64 -d|jq -r ".database[0].password"`
          export USER=`echo $PLATFORM_RELATIONSHIPS|base64 -d|jq -r ".database[0].username"`
          export DATABASE=`echo $PLATFORM_RELATIONSHIPS|base64 -d|jq -r ".database[0].path"`
          java -jar -Xmx$(jq .info.limits.memory /run/config.json)m -XX:+ExitOnOutOfMemoryError  \
          -Dserver.host=$HOST \
          -Dserver.database=$DATABASE \
          -Dserver.user=$USER \
          -Dserver.password=$PASSWORD \
          target/microprofile-microbundle.jar --port $PORT

Therefore, you can have the configuration or just migrate the application that already exists to Upsun.

References

Related to

java
payara