Struct RecordHeader 

pub struct RecordHeader {
    pub magic: u32,
    pub format_version: u16,
    pub record_type: u32,
    pub lsn: u64,
    pub tenant_id: u64,
    pub vshard_id: u32,
    pub payload_len: u32,
    pub database_id: u64,
    pub apply_key: u64,
    pub event_source: u8,
    pub commit_hlc: u64,
    pub crc32c: u32,
}

WAL record header (fixed 63 bytes).

Fields

magic: u32

format_version: u16

record_type: u32

lsn: u64

tenant_id: u64

vshard_id: u32

payload_len: u32

database_id: u64

Database scope for this record, as the raw u64 of a DatabaseId. Decoded exactly as written. Covered by CRC32C. Occupies bytes 34–41.

apply_key: u64

The idempotency key of the replicated proposal whose apply appended this record, 0 for a record no proposal apply appended. The record and the key are durable together, so a node recovers which proposals it applied from the records themselves. Covered by CRC32C. Occupies bytes 42–49.

event_source: u8

The event source of the row write this record carries, as the writer’s code. NO_EVENT_SOURCE for a record that carries no row write. Covered by CRC32C. Occupies byte 50.

commit_hlc: u64

HLC wall time, in nanoseconds, at which the write this record belongs to committed, or the proposer’s stamp of the metadata entry whose apply appended it. 0 for a record that belongs to neither: a cluster restore judges such a record by its WAL position, never by a clock. A restore keeps a record with a nonzero value only when it is below the restore point’s watermark. Covered by CRC32C. Occupies bytes 51–58.

crc32c: u32

Implementations

impl RecordHeader

pub fn to_bytes(&self) -> [u8; 63]

pub fn from_bytes(buf: &[u8; 63]) -> Self

pub fn compute_checksum(&self, payload: &[u8]) -> u32

CRC32C over header (excluding the crc32c field) + payload.

The apply key is included in the CRC so it cannot be silently modified without detection.

pub fn logical_record_type(&self) -> u32

Logical record type with the encryption flag stripped.

pub fn validate(&self, offset: u64) -> Result<()>

Trait Implementations

impl Clone for RecordHeader

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RecordHeader

impl Debug for RecordHeader

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

Formats the value using the given formatter.

impl Eq for RecordHeader

impl PartialEq for RecordHeader

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for RecordHeader