Struct DocumentHeader 

pub struct DocumentHeader {
    pub collection_id: u32,
    pub type_version: u32,
    pub payload_len: u32,
    pub payload_crc32c: u32,
}

In-memory representation of the per-document record header.

Constructed by DocumentHeader::read_from (on decode) or by the codec on encode. All four fields are stored on disk as little-endian u32.

Fields

collection_id: u32

The catalog-assigned id of the collection this record belongs to. Decode rejects mismatches with Error::CollectionIdMismatch.

type_version: u32

Document::VERSION of the type that wrote this record.

payload_len: u32

Number of payload bytes that follow this header.

payload_crc32c: u32

CRC32C of the payload bytes only — the page-trailer CRC32C on the containing leaf covers everything else.

Implementations

impl DocumentHeader

pub fn write_to(&self, dst: &mut Vec<u8>)

Write the header into dst. Appends exactly DOC_HEADER_SIZE bytes.

Used by crate::codec::encode; the format is the canonical disk shape so the buffer can be handed straight to BTree::insert without further wrapping.

pub fn read_from(bytes: &[u8]) -> Result<Self>

Decode a header from bytes. Validates only the layout (length >= DOC_HEADER_SIZE); semantic checks (CRC, collection-id, version range) are the caller’s responsibility.

Errors

Returns Error::Corruption with page_id = 0 if bytes is shorter than DOC_HEADER_SIZE.

Trait Implementations

impl Clone for DocumentHeader

fn clone(&self) -> DocumentHeader

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DocumentHeader

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

Formats the value using the given formatter.

impl PartialEq for DocumentHeader

fn eq(&self, other: &DocumentHeader) -> 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 Copy for DocumentHeader

impl Eq for DocumentHeader

impl StructuralPartialEq for DocumentHeader