Struct ObjectStoreChunkReader 

pub struct ObjectStoreChunkReader { /* private fields */ }

Adapter to convert ObjectStore to AsyncChunkReader for orc-rust.

This adapter bridges the gap between DataFusion’s ObjectStore abstraction and orc-rust’s AsyncChunkReader trait, enabling ORC files to be read from any supported object store (local filesystem, S3, GCS, Azure, etc.).

When metrics are provided, it automatically tracks:

• bytes_scanned: Total bytes read from the object store
• io_requests: Number of I/O operations performed

Implementations

impl ObjectStoreChunkReader

pub fn new(store: Arc<dyn ObjectStore>, path: Path) -> Self

Create a new ObjectStoreChunkReader

pub fn with_size(store: Arc<dyn ObjectStore>, path: Path, size: u64) -> Self

Create with known file size (for optimization)

pub fn with_metrics(self, bytes_scanned: Count, io_requests: Count) -> Self

Attach metrics counters to track I/O statistics.

When metrics are attached, every read operation will automatically update the bytes_scanned and io_requests counters.

Example

use datafusion_datasource_orc::metrics::OrcFileMetrics;

let metrics = OrcFileMetrics::new(0, "file.orc", &metrics_set);
let reader = ObjectStoreChunkReader::with_size(store, path, size)
    .with_metrics(metrics.bytes_scanned.clone(), metrics.io_requests.clone());

Trait Implementations

impl AsyncChunkReader for ObjectStoreChunkReader

fn len(&mut self) -> BoxFuture<'_, Result<u64>>

fn get_bytes( &mut self, offset_from_start: u64, length: u64, ) -> BoxFuture<'_, Result<Bytes>>