Struct ObjectMeta 

pub struct ObjectMeta {
    pub draft: DraftVersion,
    pub stream_kind: DataStreamType,
    pub track_alias: Option<u64>,
    pub group_id: u64,
    pub subgroup_id: Option<u64>,
    pub object_id: u64,
    pub publisher_priority: Option<u8>,
    pub index_in_stream: u64,
    pub payload_len: u64,
    pub status: Option<u64>,
    pub end_of_range: Option<AnyFetchEndOfRange>,
}

A framed object’s identity and framing, without its payload.

Every field is a primitive, so an observer never has to name a per-draft codec type to key on an object. Produced by ObjectFramer.

Fields

draft: DraftVersion

The draft this stream was parsed as.

stream_kind: DataStreamType

Whether this object came from a subgroup or a fetch stream.

track_alias: Option<u64>

Track alias from the stream header. None on fetch streams, whose headers carry a request ID instead.

group_id: u64

Group ID: from the stream header on subgroup streams, from the object itself on fetch streams.

subgroup_id: Option<u64>

Subgroup ID. None when the frame has none to report, which happens two ways. On a subgroup stream, when the stream type encodes an implicit subgroup ID that this draft never resolves — eight drafts (11, 12, 13, 14, 16, 17, 18 and 19) define a subgroup ID is the first object’s ID mode that the codec stores as zero, and reporting that zero would mis-key any matcher.

On a fetch stream, when the frame carried no Subgroup ID at all: from draft-15 a fetch object may be marked as having been forwarded over a datagram, which has no subgroup, and an End of Range indicator names a Location rather than an object. Both cases reach this crate as has_subgroup_id: false on the codec’s meta, behind a subgroup ID field that holds a placeholder — the same zero, and the same mis-keying if it were forwarded.

object_id: u64

Absolute Object ID, resolved from delta encoding on drafts 14-19.

publisher_priority: Option<u8>

Publisher priority. None when the header set a default-priority flag and omitted the field (drafts 15+).

index_in_stream: u64

Zero-based index of this object within its stream.

payload_len: u64

Declared payload length in bytes.

status: Option<u64>

Object Status wire code; None when a non-empty payload followed.

end_of_range: Option<AnyFetchEndOfRange>

Which End of Range indicator this frame is, or None for an object.

Drafts 16-19 let a fetch stream state that a run of Objects was not serialized instead of sending them, and those frames arrive through the same reader call as objects do. They are not objects: they carry no payload and no content, and one of them standing in a count of objects is a count that is wrong. An observer that means “objects” filters on this being None; one that means “frames” does not.

Always None on a subgroup stream, and on every fetch stream of drafts 07-15, which have no such frame.

Trait Implementations

impl Clone for ObjectMeta

fn clone(&self) -> ObjectMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ObjectMeta

impl Debug for ObjectMeta

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

Formats the value using the given formatter.

impl Eq for ObjectMeta

impl PartialEq for ObjectMeta

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ObjectMeta