bee_storage/
backend.rs

1// Copyright 2020-2021 IOTA Stiftung
2// SPDX-License-Identifier: Apache-2.0
3
4//! This module forms the backend layer which holds the contracts of starting and shutting down the backend, as well as
5//! accessing backend properties.
6
7use serde::de::DeserializeOwned;
8
9use crate::system::StorageHealth;
10
11/// Trait to be implemented on a storage backend.
12/// Determines how to start and shutdown the backend.
13pub trait StorageBackend: Send + Sized + Sync + 'static {
14    /// Helps build the associated `Config`.
15    type ConfigBuilder: Default + DeserializeOwned + Into<Self::Config>;
16    /// Holds the backend options.
17    type Config: Clone + Send + Sync;
18    /// Returned on failed operations.
19    type Error: std::error::Error + Send;
20
21    /// Initializes and starts the backend.
22    fn start(config: Self::Config) -> Result<Self, Self::Error>;
23
24    /// Shutdowns the backend.
25    fn shutdown(self) -> Result<(), Self::Error>;
26
27    /// Returns the size of the database in bytes.
28    /// Not all backends may be able to provide this operation.
29    fn size(&self) -> Result<Option<usize>, Self::Error>;
30
31    /// Returns the health status of the database.
32    /// Not all backends may be able to provide this operation.
33    fn get_health(&self) -> Result<Option<StorageHealth>, Self::Error>;
34
35    /// Sets the health status of the database.
36    /// Not all backends may be able to provide this operation.
37    fn set_health(&self, health: StorageHealth) -> Result<(), Self::Error>;
38}
bee_storage/backend.rs

bee_storage/
backend.rs
