Struct AssignmentSnapshot 

pub struct AssignmentSnapshot {
    pub version: u64,
    pub vnodes: BTreeMap<u32, NodeId>,
    pub updated_at_ms: i64,
}

Durable vnode-to-instance assignment snapshot.

Fields

version: u64

Monotonic version. Writers bump on each update.

vnodes: BTreeMap<u32, NodeId>

Vnode id → owning instance. BTreeMap (not Vec) so snapshots with different vnode_count are still deserializable — sparse indices surface as missing keys the caller can diagnose.

updated_at_ms: i64

Wall-clock timestamp of the last update, millis since epoch.

Implementations

impl AssignmentSnapshot

pub fn empty() -> Self

Empty snapshot at version 0.

pub fn next(&self, vnodes: BTreeMap<u32, NodeId>) -> Self

Next snapshot with bumped version and current wall-clock time.

pub fn vnodes_from_vec(assignment: &[NodeId]) -> BTreeMap<u32, NodeId>

Convert a Vec<NodeId> (one entry per vnode id, dense) into the BTreeMap shape this snapshot uses. Mirrors the layout returned by round_robin_assignment.

pub fn to_vnode_vec(&self, vnode_count: u32) -> Vec<NodeId>

Dense Vec<NodeId> of length vnode_count. Missing entries (a stale snapshot from a smaller vnode topology) are filled with NodeId::UNASSIGNED so callers can detect the mismatch.

Trait Implementations

impl Clone for AssignmentSnapshot

fn clone(&self) -> AssignmentSnapshot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for AssignmentSnapshot

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AssignmentSnapshot

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for AssignmentSnapshot

fn eq(&self, other: &AssignmentSnapshot) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for AssignmentSnapshot

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for AssignmentSnapshot

impl StructuralPartialEq for AssignmentSnapshot