Struct ShardManifest 

pub struct ShardManifest {
    pub shard_id: Option<Uuid>,
    pub version: u64,
    pub shard_spec_id: u32,
    pub writer_epoch: u64,
    pub replay_after_wal_entry_position: u64,
    pub wal_entry_position_last_seen: u64,
    pub current_generation: u64,
    pub flushed_generations: Vec<FlushedGeneration>,
}

Shard manifest containing epoch-based fencing and WAL state. Each shard has exactly one active writer at any time.

Fields

shard_id: Option<Uuid>

Shard identifier (UUID v4).

version: u64

Manifest version number. Matches the version encoded in the filename.

shard_spec_id: u32

Shard spec ID this shard was created with. Set at shard creation and immutable thereafter. A value of 0 indicates a manually-created shard not governed by any spec.

writer_epoch: u64

Writer fencing token - monotonically increasing. A writer must increment this when claiming the shard.

replay_after_wal_entry_position: u64

The most recent WAL entry position (0-based) that has been flushed to a MemTable. During recovery, replay starts from replay_after_wal_entry_position + 1.

wal_entry_position_last_seen: u64

The most recent WAL entry position (0-based) at the time manifest was updated. This is a hint, not authoritative - recovery must list files to find actual state.

current_generation: u64

Next generation ID to create (incremented after each MemTable flush).

flushed_generations: Vec<FlushedGeneration>

List of flushed MemTable generations and their directory paths.

Trait Implementations

impl Clone for ShardManifest

fn clone(&self) -> ShardManifest

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ShardManifest

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

Formats the value using the given formatter.

impl Default for ShardManifest

fn default() -> Self

Returns the “default value” for a type.

impl Message for ShardManifest

fn encoded_len(&self) -> usize

Returns the encoded length of the message without a length delimiter.

fn clear(&mut self)

Clears the message, resetting all fields to their default.

fn encode(&self, buf: &mut impl BufMut) -> Result<(), EncodeError>

where Self: Sized,

Encodes the message to a buffer.

fn encode_to_vec(&self) -> Vec<u8>

where Self: Sized,

Encodes the message to a newly allocated buffer.

fn encode_length_delimited( &self, buf: &mut impl BufMut, ) -> Result<(), EncodeError>

where Self: Sized,

Encodes the message with a length-delimiter to a buffer.

fn encode_length_delimited_to_vec(&self) -> Vec<u8>

where Self: Sized,

Encodes the message with a length-delimiter to a newly allocated buffer.

fn decode(buf: impl Buf) -> Result<Self, DecodeError>

where Self: Default,

Decodes an instance of the message from a buffer.

fn decode_length_delimited(buf: impl Buf) -> Result<Self, DecodeError>

where Self: Default,

Decodes a length-delimited instance of the message from the buffer.

fn merge(&mut self, buf: impl Buf) -> Result<(), DecodeError>

where Self: Sized,

Decodes an instance of the message from a buffer, and merges it into self.

fn merge_length_delimited(&mut self, buf: impl Buf) -> Result<(), DecodeError>

where Self: Sized,

Decodes a length-delimited instance of the message from buffer, and merges it into self.

impl Name for ShardManifest

const NAME: &'static str = "ShardManifest"

Simple name for this Message. This name is the same as it appears in the source .proto file, e.g. FooBar.

const PACKAGE: &'static str = "lance.table"

Package name this message type is contained in. They are domain-like and delimited by ., e.g. google.protobuf.

fn full_name() -> String

Fully-qualified unique name for this Message. It’s prefixed with the package name and names of any parent messages, e.g. google.rpc.BadRequest.FieldViolation. By default, this is the package name followed by the message name. Fully-qualified names must be unique within a domain of Type URLs.

fn type_url() -> String

Type URL for this Message, which by default is the full name with a leading slash, but may also include a leading domain name, e.g. type.googleapis.com/google.profile.Person. This can be used when serializing into the google.protobuf.Any type.

impl PartialEq for ShardManifest

fn eq(&self, other: &ShardManifest) -> 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 StructuralPartialEq for ShardManifest