Struct DatagramObject

Source

pub struct DatagramObject {
    pub datagram_type: DatagramType,
    pub track_alias: VarInt,
    pub group_id: VarInt,
    pub object_id: VarInt,
    pub publisher_priority: u8,
    pub extension_headers: Vec<u8>,
    pub status: Option<ObjectStatus>,
    pub payload: Vec<u8>,
}

Expand description

Datagram carrying a single object.

Fields§

§datagram_type: DatagramType

Datagram type byte.

§track_alias: VarInt

Track alias.

§group_id: VarInt

Group ID.

§object_id: VarInt

Object ID. Defaults to 0 when DatagramType::object_id_present is false.

§publisher_priority: u8

Publisher priority.

§extension_headers: Vec<u8>

Raw extension-header bytes (empty unless DatagramType::extensions_present is true).

§status: Option<ObjectStatus>

Object status (only present for status-type datagrams).

§payload: Vec<u8>

Object payload (empty for status-type datagrams).

Implementations§

Source §

impl DatagramObject

Source

pub fn encode_checked(&self, buf: &mut impl BufMut) -> Result<(), CodecError>

Encode the datagram in full, refusing a field the type byte cannot carry.

Draft-14 Section 10.3.1 states the framing rule outright: “The Object Status field and Object Payload are mutually exclusive.” Types 0x00 through 0x07 carry a payload and omit the status field; types 0x20 and 0x21 carry a status field and have no payload. This value can hold both at once, and Self::encode resolves the disagreement by writing whichever one the type byte announces and discarding the other without a word. An End of Group marker written under a payload type does not arrive late or malformed — it does not arrive at all, and the receiver sees an ordinary object in its place; a payload written under a status type vanishes the same way.

ObjectStatus::Normal under a payload type is not that case and is accepted. Section 10.2.1.1 says “Any object with a status code other than zero MUST have an empty payload”, so Normal is the status a payload-bearing object already has, and stating it asks for exactly the bytes leaving it out asks for.

Errors with CodecError::InvalidField on either lossy combination, before any byte is written, so a refused datagram leaves buf untouched.

Source

pub fn encode(&self, buf: &mut impl BufMut)

Encode the datagram in full.

The type byte is taken as the authority on framing, which is what makes this infallible — and what makes it lossy when the value disagrees with itself. A status set under a payload type, or a payload set under a status type, is discarded here without a word. Prefer Self::encode_checked, which refuses those combinations instead of resolving them.

Source

pub fn decode(buf: &mut impl Buf) -> Result<Self, CodecError>

Decode a datagram. The buffer must contain the full datagram — payload-bearing types extend to the end of the QUIC datagram, which the caller is responsible for delimiting.