Crate crabka_protocol 

Kafka wire-protocol codec.

crabka-protocol is a pure-Rust library that encodes and decodes every Apache Kafka request and response message, byte-equivalent to the upstream JVM implementation. It performs no I/O and makes no async assumptions; it is intended to be consumed by broker, client, and tooling crates within the Crabka project.

Two flavors

Every message has two generated types:

• owned::FooRequest — owns its data (String, Bytes, Vec<T>). Easy to move across await points.
• borrowed::FooRequest<'a> — references slices of the input buffer (&'a str, &'a [u8]). Zero-copy decoding.

Both implement Encode; the owned flavor implements Decode and the borrowed flavor implements DecodeBorrow.

Versioning

crabka-protocol is pre-1.0. Breaking API changes per minor version are allowed; see CHANGELOG.md. The wire-protocol pin is recorded in crates/protocol/schemas/VERSION.

Encoding a generated request

use bytes::BytesMut;
use crabka_protocol::Encode;
use crabka_protocol::owned::api_versions_request::ApiVersionsRequest;

let req = ApiVersionsRequest::default();
let version = 4;
let mut buf = BytesMut::with_capacity(req.encoded_len(version));
req.encode(&mut buf, version).unwrap();
assert_eq!(buf.len(), req.encoded_len(version));

Re-exports

pub use api_key::ApiKey;

pub use tagged_fields::UnknownTaggedField;

pub use tagged_fields::UnknownTaggedFields;

Modules

api_key

borrowed

Borrowed-flavor generated message types.

kafka_3_6_2

legacy_compat

Adapters between the canonical Produce/Fetch types and the kafka_3_6_2-namespaced flavors emitted from the vendored 3.6.2 schemas. Used by the wire-router branches for Produce v0–2 and Fetch v0–3.

owned

Owned (heap-allocated) message types.

primitives

records

Typed v2 record batch decoder/encoder.

tagged_fields

KIP-482 flexible-version tagged fields.

Enums

ProtocolError

Errors that can occur during wire-protocol encoding or decoding.

Traits

Decode

Decode a Kafka wire-protocol value from a buffer at the given protocol version.

DecodeBorrow

Like Decode, but for borrowed (zero-copy) flavors. Requires a contiguous buffer because borrowed values reference slices of it.

Encode

Encode a Kafka wire-protocol value into a buffer at the given protocol version.

ProtocolRequest

Implemented by every generated Request struct in crabka-protocol.