Module data_stream 

Draft-14 data streams: subgroup streams, fetch streams, datagrams.

Draft-14 carries object data in three wire shapes:

• Subgroup stream: starts with a Type byte 0x10..=0x1D whose bit-flags determine whether a Subgroup ID field is present, whether the subgroup ID is zero or the first Object ID, whether extension headers are present, and whether the stream ends at a group boundary. Object IDs are delta-encoded relative to the previous Object ID in the same stream.

• Fetch stream: Type 0x05, Request ID, then a sequence of self-describing objects until FIN.

• Datagram: Type byte 0x00..=0x07 or 0x20..=0x21 with bit-flags for End of Group, Extensions Present, Object ID Present, and Status vs Payload.

Re-exports

use bytes::Buf; 🔒

use bytes::BufMut; 🔒

use super::types::ObjectStatus; 🔒

use crate::error::CodecError; 🔒

use crate::object_properties::ObjectProperty; 🔒

use crate::object_properties::PropertyValue; 🔒

use crate::varint::VarInt; 🔒

Structs

DatagramObject

Datagram carrying a single object.

DatagramType

Datagram type byte.

FetchGaps

The Prior Group ID Gap and Prior Object ID Gap conditions of draft-14 Section 11.1 and draft-14 Section 11.3 that one fetch stream shows.

FetchHeader

Fetch stream header: the type byte 0x05 followed by the Request ID.

FetchObject

One object carried on a fetch stream.

FetchObjectMeta

The framing of one fetch object, without its payload.

PriorGaps

The Prior Group ID Gap and Prior Object ID Gap one Object carries.

SubgroupHeader

Subgroup stream header.

SubgroupObject

One object within a subgroup stream, with the Object ID already resolved from its delta encoding.

SubgroupObjectMeta

The framing of one subgroup object, without its payload.

SubgroupObjectReader

Stateful reader for the object fields on a subgroup stream.

SubgroupStreamType

Subgroup stream type byte.

Enums

PayloadPermission

Whether an object carrying a given status may hold a non-empty payload.

Constants

FETCH_STREAM_TYPE

Draft-14 fetch stream type byte.

PRIOR_GROUP_ID_GAP

Prior Group ID Gap, Extension Header Type 0x3C (Section 11.1).

PRIOR_OBJECT_ID_GAP

Prior Object ID Gap, Extension Header Type 0x3E (Section 11.3).

Functions

check_extensions_against_status 🔒

Hold an object to the rule binding extension headers to Object Status.

collect_gaps 🔒

skip 🔒

Advance buf past len bytes without copying them.

stream_type_error 🔒

Which failure a leading unidirectional stream type that is not the one a reader wants is.