zenoh-flat

zenoh-flat is a flat, FFI-friendly facade over the zenoh crate. It re-exports the zenoh types it operates on under their own Rust names (Session, KeyExpr, ZBytes, Sample, Config, …) and exposes the entire API as free functions whose names mirror the type they act on:

let config = config_default();
let session = open(config)?;
let ke = keyexpr_try_from("demo/example".to_string())?;
session_put(&session, &ke, bytes_from_slice(b"hello"), /* … */)?;

Every public function is annotated with #[prebindgen], so prebindgen captures this surface and generates idiomatic bindings for other languages (C via lang::Cbindgen, Kotlin/JNI via lang::JniGen, …) — no hand-written FFI layer per target language.

Conventions

• Naming follows zenoh's Rust names, not zenoh-c. Functions are <type>_<verb> (session_declare_publisher, publisher_undeclare, keyexpr_intersects); type aliases keep zenoh's own identifier (ZBytes, ZenohId).
• Callback-based, no channels. Subscribers, queryables, queriers, scouts and liveliness subscribers deliver items through an impl Fn(..) callback plus an on_close hook. This keeps the surface trivially FFI-exportable.
• Errors as Result<T, Error>. Error is zenoh's boxed error; the error_message accessor renders it to a String for callers that cannot carry a Rust error across the boundary.
• Opaque handles vs. value types. Handle types (Session, Publisher, Sample, …) cross as opaque pointers; enums and small structs cross by value.

Layout

All API lives under src/base/, grouped by area (keyexpr, config, bytes, session, publisher, subscriber, query, sample, scouting, liveliness, time, qos) and re-exported flat from zenoh_flat::*.

Features

Feature flags forward to zenoh and mirror zenoh-c's defaults. unstable additionally enables the #[unstable] slices of the API (Reliability, entity-id accessors, key-expression relations, sample source info); it is off by default.