lance-namespace-impls

Lance Namespace implementation backends.

Overview

This crate provides concrete implementations of the Lance namespace trait:

• Unified connection interface for all implementations
• REST Namespace - REST API client for remote Lance namespace servers (feature: rest)
• Directory Namespace - File system-based namespace that stores tables as Lance datasets (always available)

Features

REST Namespace (feature: rest)

The REST namespace implementation provides a client for connecting to remote Lance namespace servers via REST API.

Directory Namespace (always available)

The directory namespace implementation stores tables as Lance datasets in a directory structure on local or cloud storage.

Supported storage backends:

• Local filesystem (always available)
• AWS S3 (feature: dir-aws)
• Google Cloud Storage (feature: dir-gcp)
• Azure Blob Storage (feature: dir-azure)
• Alibaba Cloud OSS (feature: dir-oss)

Usage

Connecting to a Namespace

use lance_namespace_impls::connect;
use std::collections::HashMap;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connect to REST implementation
    let mut props = HashMap::new();
    props.insert("uri".to_string(), "http://localhost:8080".to_string());
    let namespace = connect("rest", props).await?;

    Ok(())
}

Using Directory Namespace

use lance_namespace_impls::connect;
use std::collections::HashMap;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connect to local directory
    let mut props = HashMap::new();
    props.insert("root".to_string(), "/path/to/data".to_string());
    let namespace = connect("dir", props).await?;

    // Connect to S3
    let mut props = HashMap::new();
    props.insert("root".to_string(), "s3://my-bucket/path".to_string());
    props.insert("storage.region".to_string(), "us-west-2".to_string());
    let namespace = connect("dir", props).await?;

    Ok(())
}

Configuration

Directory Namespace Properties

• root - Root path for the namespace (local path or cloud storage URI)
• storage.* - Storage-specific options (e.g., storage.region, storage.access_key_id)

Documentation

For more information about Lance and its namespace system, see the Lance Namespace documentation.