Crate cesr 

CESR + KERI primitives for Rust as a single feature-gated crate.

Architecture: one wire message, three modules

A KERI key event message is a serialized event body followed by CESR-framed attachments:

{"v":"KERI10JSON000189_","t":"icp","d":"EAgi…",…} -VAt -AAC AADB_mVj…88ch ABAN5tRO…88ch
└──────────────────── body ─────────────────────┘└─────────── attachments ────────────┘
                                                  │    │    └ two indexed Ed25519 sigs
                                                  │    └ `-A` ControllerIdxSigs, count 2
                                                  └ `-V` attachment frame, size in quadlets

Each module owns one verb over that message:

• [stream] finds it — cold-start detection and version-string framing slice the body span; counters delimit the attachment groups.
• [keri] names it — the typed domain: events, identifiers, seals, thresholds. Pure data, no serialization of its own.
• core spells it — the CESR primitive alphabet (Matter, indexers, counters) that every layer above composes; b64 is its Base64 codec, [crypto] its digests, keypairs, and verifiers.

The body codec — the strict canonical JSON parser with in-place SAID verification, the builders that write keripy’s exact bytes back, and the end-to-end read and write spines over them — lives in the keri-codec crate, which composes this crate’s stream framing with keri’s typed domain.

Features

Each former separate crate is now a module gated by a cargo feature: b64, core, crypto, stream, keri, reachable as cesr::core::*, cesr::crypto::*, etc. (The former utils module — the CESR Base64 codec — is now b64.)

The crate is no_std-capable: std (on by default) gives the std-backed surface; build --no-default-features --features alloc,… for embedded/wasm.

Modules

b64b64

CESR Base64 codec.

corecore

CESR (Composable Event Streaming Representation) core primitives and codes.

prelude

The common imports for working with cesr.

Structs

Datercore

ISO-8601 DateTime encoded as CESR Matter. Code is always MatterCode::DateTime (1AAG).

Mattercore

A CESR-encoded primitive with typed code C, a raw payload, and an optional soft field.

Numbercore

An unsigned integer with an automatically selected CESR number code.

Seqnercore

CESR sequence number, wrapping a Number for event ordering.

Sigercore

An indexed signature primitive.

Enums

CesrVersioncore

CESR protocol version for code table selection.

Type Aliases

Cigarcore

Non-indexed signature

Digercore

Digest — holds a hash value

Labelercore

Label primitive — field name or tag

Noncercore

Nonce/UUID primitive — salt, digest, or empty

Prefixercore

AID prefix — a verification key used as an autonomic identifier

Saidercore

Self-addressing identifier (SAID) — a digest used as a content identifier

Signercore

Signing key seed — can produce signatures (actual crypto in cesr-crypto)

Textercore

Text primitive — variable-length byte string

Verfercore

Verification key — can verify signatures

Versercore

Version primitive — encodes protocol/genus version info