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Contributing to Lance Namespace Implementations

The Lance Namespace Implementations codebase is at lance-format/lance-namespace-impls. This repository contains namespace implementations for various catalog systems that integrate with the Lance format.

For contributing changes to the Lance Namespace specification or generated clients, please go to the lance-namespace repo.

For contributing changes to directory and REST namespaces, please go to the lance repo.

Repository structure

This repository currently contains the following components:

Component Language Path Description
Glue Namespace Java java/lance-namespace-glue AWS Glue catalog implementation
Hive2 Namespace Java java/lance-namespace-hive2 Hive Metastore 2.x implementation
Hive3 Namespace Java java/lance-namespace-hive3 Hive Metastore 3.x implementation
Unity Namespace Java java/lance-namespace-unity Databricks Unity Catalog implementation
Polaris Namespace Java java/lance-namespace-polaris Apache Polaris catalog implementation
Glue Namespace Python python/src/lance_namespace_impls/glue.py AWS Glue catalog implementation
Hive Namespace Python python/src/lance_namespace_impls/hive.py Hive Metastore implementation
Unity Namespace Python python/src/lance_namespace_impls/unity.py Unity Catalog implementation

Development Setup

Install uv

We use uv for Python development. Make sure it is installed.

Java Development

cd java
./mvnw install

Python Development

cd python
uv sync
uv run pytest

Build

Top-level commands available:

  • make clean: Remove all build artifacts
  • make build: Build all modules
  • make test: Run all tests

Language-specific commands:

  • make clean-java: Clean Java modules
  • make build-java: Build Java modules
  • make test-java: Test Java modules
  • make clean-python: Clean Python modules
  • make build-python: Build Python modules
  • make test-python: Test Python modules

Documentation

The documentation is built using mkdocs-material.

cd docs
make serve  # Start local server
make build  # Build static site

Release Process

This section describes the CI/CD workflows for automated version management, releases, and publishing.

Version Scheme

  • Stable releases: X.Y.Z (e.g., 1.2.3)
  • Preview releases: X.Y.Z-beta.N (e.g., 1.2.3-beta.1)

Creating a Release

  1. Create Release Draft
  2. Go to Actions -> "Create Release"
  3. Select parameters:
    • Release type (major/minor/patch)
    • Release channel (stable/preview)
    • Dry run (test without pushing)

  4. Run workflow (creates a draft release)

  5. Review and Publish

  6. Go to the Releases page to review the draft
  7. Edit release notes if needed
  8. Click "Publish release" to:
    • For stable releases: Trigger automatic publishing for Java and Python
    • For preview releases: Create a beta release (not published)