Struct Metadata 

pub struct Metadata { /* private fields */ }

Validated envelope metadata.

Invariants:

• Length is in 1..=MAX_METADATA_LEN. Empty metadata is rejected — use Option::<Metadata>::None to represent “absent.” This avoids the bytes::Bytes::slice(empty) footgun where an empty slice orphans from the parent buffer’s STATIC_VTABLE (the footgun is documented on crate::envelope::PersistedEnvelope::metadata_bytes).
• The non-empty invariant is wire-format-driven: u32::MAX is the absent-metadata sentinel in the wire encoding, so Some(Metadata) on the read path always carries actual bytes.

Backed by Bytes for Arc-shared ownership.

Implementations

impl Metadata

pub fn from_bytes(bytes: Bytes) -> Result<Self, ValueError>

Construct from arbitrary bytes, validating non-empty and size cap.

Errors

• ValueError::MetadataEmpty if bytes.is_empty().
• ValueError::MetadataTooLong if bytes.len() > MAX_METADATA_LEN.

pub fn as_slice(&self) -> &[u8]

Borrow as &[u8]. Zero-cost.

pub fn into_bytes(self) -> Bytes

Take ownership of the inner Bytes (one Arc share, no copy).

Trait Implementations

impl Clone for Metadata

fn clone(&self) -> Metadata

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Metadata

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

Formats the value using the given formatter.

impl Eq for Metadata

impl Hash for Metadata

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Metadata

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Metadata