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Snapshotable

lora_database

Trait Snapshotable 

Source 
pub trait Snapshotable {
    // Required methods
    fn save_snapshot<W>(&self, writer: W) -> Result<SnapshotMeta, SnapshotError>
       where W: Write;
    fn load_snapshot<R>(
        &mut self,
        reader: R,
    ) -> Result<SnapshotMeta, SnapshotError>
       where R: Read;
    fn save_checkpoint<W>(
        &self,
        writer: W,
        wal_lsn: u64,
    ) -> Result<SnapshotMeta, SnapshotError>
       where W: Write;
}
Expand description

A backend that can serialize its state to a byte stream and restore from one.

The trait is deliberately orthogonal to [GraphStorage] / [GraphStorageMut]: a backend opts into durability independently of the core read/write contract. Future hooks (WAL, incremental checkpoints) will land alongside this trait, not inside it — keeping Snapshotable narrow makes it easy to compose (e.g. SnapshotOverS3, or a wrapper that also appends to a WAL on every mutation).

Required Methods§

Source

fn save_snapshot<W>(&self, writer: W) -> Result<SnapshotMeta, SnapshotError>
where W: Write,

Source

fn load_snapshot<R>(&mut self, reader: R) -> Result<SnapshotMeta, SnapshotError>
where R: Read,

Source

fn save_checkpoint<W>( &self, writer: W, wal_lsn: u64, ) -> Result<SnapshotMeta, SnapshotError>
where W: Write,

Save a snapshot stamped with a WAL log position, suitable as a checkpoint fence. The fence is the LSN past which the WAL is the source of truth on recovery; replay skips records at or below it.

Required (no default) because a fence-less default would silently break recovery for any backend that opted into a WAL — every backend that implements Snapshotable must be able to produce a checkpoint. The only in-tree impl (InMemoryGraph) just calls write_snapshot with Some(wal_lsn).

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.

Implementors§