Trait Snapshot

pub trait Snapshot {
    // Provided methods
    fn echo(&self, echo_request: RequestEcho) -> ResponseEcho { ... }
    fn list_snapshots(
        &self,
        _list_snapshots_request: RequestListSnapshots,
    ) -> ResponseListSnapshots { ... }
    fn offer_snapshot(
        &self,
        _offer_snapshot_request: RequestOfferSnapshot,
    ) -> ResponseOfferSnapshot { ... }
    fn load_snapshot_chunk(
        &self,
        _load_snapshot_chunk_request: RequestLoadSnapshotChunk,
    ) -> ResponseLoadSnapshotChunk { ... }
    fn apply_snapshot_chunk(
        &self,
        _apply_snapshot_chunk_request: RequestApplySnapshotChunk,
    ) -> ResponseApplySnapshotChunk { ... }
    fn flush(&self, _flush_request: RequestFlush) -> ResponseFlush { ... }
}

Available on crate feature sync-api only.

Trait for serving and restoring tendermint’s state sync snapshots.

Details

State sync allows new nodes to rapidly bootstrap by discovering, fetching, and applying state machine snapshots instead of replaying historical blocks. For more details, see the state sync section.

When a new node is discovering snapshots in the P2P network, existing nodes will call list_snapshots on the application to retrieve any local state snapshots. The new node will offer these snapshots to its local application via offer_snapshot.

Once the application accepts a snapshot and begins restoring it, Tendermint will fetch snapshot chunks from existing nodes via load_snapshot_chunk and apply them sequentially to the local application with apply_snapshot_chunk. When all chunks have been applied, the application app_hash is retrieved via an info query and compared to the blockchain’s app_hash verified via light client.

Provided Methods

fn echo(&self, echo_request: RequestEcho) -> ResponseEcho

Echo a string to test abci client/server implementation.

fn list_snapshots( &self, _list_snapshots_request: RequestListSnapshots, ) -> ResponseListSnapshots

Used during state sync to discover available snapshots on peers.

fn offer_snapshot( &self, _offer_snapshot_request: RequestOfferSnapshot, ) -> ResponseOfferSnapshot

OfferSnapshot is called when bootstrapping a node using state sync.

fn load_snapshot_chunk( &self, _load_snapshot_chunk_request: RequestLoadSnapshotChunk, ) -> ResponseLoadSnapshotChunk

Used during state sync to retrieve snapshot chunks from peers.

fn apply_snapshot_chunk( &self, _apply_snapshot_chunk_request: RequestApplySnapshotChunk, ) -> ResponseApplySnapshotChunk

Applies the snapshot chunks received from load_snapshot_chunk

fn flush(&self, _flush_request: RequestFlush) -> ResponseFlush

Signals that messages queued on the client should be flushed to the server.

Implementors