crates/iceberg/README.md

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# Apache Iceberg Official Native Rust Implementation

[![crates.io](https://img.shields.io/crates/v/iceberg.svg)](https://crates.io/crates/iceberg)
[![docs.rs](https://img.shields.io/docsrs/iceberg.svg)](https://docs.rs/iceberg/latest/iceberg/)

This crate contains the official Native Rust implementation of [Apache Iceberg](https://rust.iceberg.apache.org/).

See the [API documentation](https://docs.rs/iceberg/latest) for examples and the full API.

## Usage

```rust
use futures::TryStreamExt;
use iceberg::io::{FileIO, FileIOBuilder};
use iceberg::{Catalog, Result, TableIdent};
use iceberg_catalog_memory::MemoryCatalog;

#[tokio::main]
async fn main() -> Result<()> {
    // Build your file IO.
    let file_io = FileIOBuilder::new("memory").build()?;
    // Connect to a catalog.
    let catalog = MemoryCatalog::new(file_io, None);
    // Load table from catalog.
    let table = catalog
        .load_table(&TableIdent::from_strs(["hello", "world"])?)
        .await?;
    // Build table scan.
    let stream = table
        .scan()
        .select(["name", "id"])
        .build()?
        .to_arrow()
        .await?;

    // Consume this stream like arrow record batch stream.
    let _data: Vec<_> = stream.try_collect().await?;
    Ok(())
}
```

## IO Support

Iceberg Rust provides various storage backends through feature flags. Here are the currently supported storage backends:

| Storage Backend      | Feature Flag     | Status         | Description                                   |
| -------------------- | ---------------- | -------------- | --------------------------------------------- |
| Memory               | `storage-memory` | ✅ Stable       | In-memory storage for testing and development |
| Local Filesystem     | `storage-fs`     | ✅ Stable       | Local filesystem storage                      |
| Amazon S3            | `storage-s3`     | ✅ Stable       | Amazon S3 storage                             |
| Google Cloud Storage | `storage-gcs`    | ✅ Stable       | Google Cloud Storage                          |
| Alibaba Cloud OSS    | `storage-oss`    | 🧪 Experimental | Alibaba Cloud Object Storage Service          |
| Azure Datalake       | `storage-azdls`  | 🧪 Experimental | Azure Datalake Storage v2                     |

You can enable all stable storage backends at once using the `storage-all` feature flag. 

> Note that `storage-oss` and `storage-azdls` are currently experimental and not included in `storage-all`.

Example usage in `Cargo.toml`:

```toml
[dependencies]
iceberg = { version = "x.y.z", features = ["storage-s3", "storage-fs"] }
```