core/server_common/src/storage.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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use std::io;

/// Positional byte io over a durable backing store.
pub trait Storage {
    type Buffer;

    fn write_at(&self, offset: usize, buf: Self::Buffer)
    -> impl Future<Output = io::Result<usize>>;

    fn read_at(
        &self,
        offset: usize,
        buffer: Self::Buffer,
    ) -> impl Future<Output = io::Result<Self::Buffer>>;
}