Enum AnyFetchHeader 

pub enum AnyFetchHeader {
    Draft07(FetchHeader),
    Draft08(FetchHeader),
    Draft09(FetchHeader),
    Draft10(FetchHeader),
    Draft11(FetchHeader),
    Draft12(FetchHeader),
    Draft13(FetchHeader),
    Draft14(FetchHeader),
    Draft15(FetchHeader),
    Draft16(FetchHeader),
    Draft17(FetchHeader),
    Draft18(FetchHeader),
    Draft19(FetchHeader),
}

A fetch header from any enabled draft.

Note: Header structure varies significantly across drafts. Draft-07 has a minimal fetch header, Draft-14 has a full header.

Variants

Draft07(FetchHeader)

Draft-draft07 variant.

Draft08(FetchHeader)

Draft-draft08 variant.

Draft09(FetchHeader)

Draft-draft09 variant.

Draft10(FetchHeader)

Draft-draft10 variant.

Draft11(FetchHeader)

Draft-draft11 variant.

Draft12(FetchHeader)

Draft-draft12 variant.

Draft13(FetchHeader)

Draft-draft13 variant.

Draft14(FetchHeader)

Draft-draft14 variant.

Draft15(FetchHeader)

Draft-draft15 variant.

Draft16(FetchHeader)

Draft-draft16 variant.

Draft17(FetchHeader)

Draft-draft17 variant.

Draft18(FetchHeader)

Draft-draft18 variant.

Draft19(FetchHeader)

Draft-draft19 variant.

Implementations

impl AnyFetchHeader

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

Decode from wire using the specified draft version.

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

Encode to wire using the appropriate draft’s format.

pub fn draft(&self) -> DraftVersion

Returns the draft version this value belongs to.

impl AnyFetchHeader

pub fn request_id(&self) -> u64

The id of the request this fetch stream answers.

Every draft puts it in the header and nothing else: drafts 07-10 call it the Subscribe ID and drafts 11-19 the Request ID, and it names the request the publisher is responding to either way. Draft-19 Section 11.4.4: “When a stream begins with FETCH_HEADER, all objects on the stream belong to the track requested in the Fetch message identified by Request ID.”

It is what ties a fetch data stream back to the control exchange that opened it, which is the only route by which anything the stream does not state — on drafts 18 and 19, the Group Order its Group ID Deltas resolve against — can reach a reader.

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

As AnySubgroupHeader::encode_stream, for fetch streams.

Fetch was the carrier this pair was missing: decode_stream has existed here all along with nothing on the other side of it, so a fetch stream the codec wrote could not be read back by the codec.

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

As AnySubgroupHeader::decode_stream, for fetch streams.

Trait Implementations

impl Clone for AnyFetchHeader

fn clone(&self) -> AnyFetchHeader

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AnyFetchHeader

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

Formats the value using the given formatter.