Function validate_slice_routing

nodedb-cluster/src/distributed_array/handler.rs:199–217

Validate that a SLICE request is routed to the correct shard. Returns `Ok(())` when `prefix_bits == 0` (no validation) or when `local_vshard_id` falls within the Hilbert ranges carried by the request. Returns `Err(ClusterError::WrongOwner)` when this shard no longer covers any of the requested ranges, indicating a stale routing table.

(req: &ArrayShardSliceReq, local_vshard_id: u32)

/// Returns `Err(ClusterError::WrongOwner)` when this shard no longer covers
/// any of the requested ranges, indicating a stale routing table.
fn validate_slice_routing(req: &ArrayShardSliceReq, local_vshard_id: u32) -> Result<()> {
    if req.prefix_bits == 0 || req.slice_hilbert_ranges.is_empty() {
        return Ok(());
    }
    // Compute which vShards overlap the slice ranges. If local_vshard_id is not
    // among them, this node no longer owns the required Hilbert range.
    let covered = array_vshards_for_slice(
        &req.slice_hilbert_ranges,
        req.prefix_bits,
        crate::routing::VSHARD_COUNT,
    )?;
    if covered.binary_search(&local_vshard_id).is_err() {
        return Err(ClusterError::WrongOwner {
            vshard_id: local_vshard_id,
            expected_owner_node: None,
        });
    }
    Ok(())
}

/// Validate that a DELETE request is routed to the correct shard.
///