Trait VortexReadAt

pub trait VortexReadAt:
    Send
    + Sync
    + Clone
    + 'static {
    // Required methods
    fn read_at_into(
        &self,
        pos: u64,
        buffer: BytesMut,
    ) -> impl Future<Output = Result<BytesMut>> + 'static;
    fn size(&self) -> impl Future<Output = u64> + 'static;

    // Provided method
    fn performance_hint(&self) -> usize { ... }
}

A trait for types that support asynchronous reads.

References to the type must be safe to share across threads, but spawned futures may be !Send to support thread-per-core implementations.

Readers must be cheaply cloneable to allow for easy sharing across tasks or threads.

Required Methods

fn read_at_into( &self, pos: u64, buffer: BytesMut, ) -> impl Future<Output = Result<BytesMut>> + 'static

Request an asynchronous positional read to be done, with results written into the provided buffer.

This method will take ownership of the provided buffer, and upon successful completion will return the buffer completely full with data.

If the reader does not have enough data available to fill the buffer, the returned Future will complete with an io::Error.

Thread Safety

The resultant Future need not be Send, allowing implementations that use thread-per-core executors.

fn size(&self) -> impl Future<Output = u64> + 'static

Asynchronously get the number of bytes of data readable.

For a file it will be the size in bytes, for an object in an ObjectStore it will be the ObjectMeta::size.

Provided Methods

fn performance_hint(&self) -> usize

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl VortexReadAt for Buffer

fn read_at_into( &self, pos: u64, buffer: BytesMut, ) -> impl Future<Output = Result<BytesMut>> + 'static

fn size(&self) -> impl Future<Output = u64> + 'static

impl<T: VortexReadAt> VortexReadAt for Arc<T>

fn read_at_into( &self, pos: u64, buffer: BytesMut, ) -> impl Future<Output = Result<BytesMut>> + 'static

fn performance_hint(&self) -> usize

fn size(&self) -> impl Future<Output = u64> + 'static

Implementors

impl<R: VortexReadAt> VortexReadAt for OffsetReadAt<R>