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.

Structs

DatagramObject

Datagram carrying a single object.

DatagramType

Datagram type byte.

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.

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.

Functions

check_extensions_against_status 🔒

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

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.