Building a Custom Server Based on Polaris

This page highlights a few keys points for building custom servers based on Apache Polaris.

Polaris produces several jars. These jars may be used to build custom catalog server according to the terms of the license included in Polaris distributions.

General Principles

• Create a module in your project (Maven, Gradle or any other build tool) for a Quarkus Application.
• Include polaris-runtime-service as a runtime or compile-time dependency.
• Include / exclude other dependencies according to the project’s needs (e.g., an alternative JDBC driver).
• Do not include polaris-runtime-defaults or polaris-server as dependencies.
• Provide your own application.properties file for your Quarkus build.
• Define your own Quarkus Application Name and Version (do not use “Apache Polaris” as the application name).

Background

The polaris-server module is intended to be a particular way to build a Polaris server. It includes dependencies that are considered essential for the Apache Polaris distribution. This is not necessarily the case for downstream builds, which may want to exclude some features and include others (perhaps custom implementations of some Polaris SPI interfaces).

The polaris-runtime-defaults module is intended to hold application.properties configured for the default Apache Polaris distribution. While it may be tempting to reuse it in a downstream build and add overrides for some properties, practice shows that in this case it becomes very hard to predict the effects of property customizations in the downstream build. While it may be relevant to Gradle builds only, it is much more clear to have the full set of properties in a custom application.properties file without any other application.properties files in transitive dependencies.

The polaris-runtime-service module contains standard service endpoint implementations and is intended to be reused. Custom CDI beans may be used in downstream projects to override / enhance beans provided by polaris-runtime-service.