Enable set_ws_client and set_http_client injectable interfaces

Author: jhugman

.github/workflows/tests.yml

@@ -170,4 +170,10 @@ jobs:
         shell: bash
         run: |
           cargo test --verbose --target ${{ matrix.target }} -p livekit-net --features native-tokio
-          cargo test --verbose --target ${{ matrix.target }} -p livekit-api --features signal-client-tokio
+          cargo test --verbose --target ${{ matrix.target }} -p livekit-api --features signal-client-tokio
+
+      - name: Build livekit-net uniffi feature (foreign transport bindings)
+        shell: bash
+        run: |
+          cargo build --verbose --target ${{ matrix.target }} -p livekit-net --features uniffi
+          cargo build --verbose --target ${{ matrix.target }} -p livekit-net --features uniffi,native-tokio

Cargo.lock

@@ -9,6 +9,12 @@ repository.workspace = true
 [features]
 default = []
 
+# UniFFI bindings: exposes the transport seam across the FFI so a host can
+# implement WsClient/HttpClient and register it. Orthogonal to the native
+# backends — enable alongside a native-* backend for a host-overridable
+# transport that falls back to native.
+uniffi = ["dep:uniffi"]
+
 # Native backend bundles — each pairs the net libraries with a runtime.
 native-tokio      = ["__native", "__native-tokio", "tokio"]
 native-async      = ["__native", "__native-async", "async"]
@@ -50,6 +56,13 @@ __native-async = ["dep:async-tungstenite", "dep:isahc", "dep:tokio", "dep:future
 [dependencies]
 async-trait = "0.1"
 
+# Optional: scaffolding for the `uniffi` feature. `scaffolding-ffi-buffer-fns`
+# matches livekit-datatrack/livekit-uniffi so the ABI is consistent when these
+# crates are combined into one cdylib. No runtime feature: the exported traits
+# are `with_foreign` (host-driven futures) and the exported setters are sync, so
+# the crate stays runtime-agnostic.
+uniffi = { workspace = true, features = ["scaffolding-ffi-buffer-fns"], optional = true }
+
 # Direct path dep (not workspace inheritance) so default-features = false is
 # honored: cargo ignores a member's default-features override on an inherited dep,
 # which would drag in livekit-runtime's default `tokio` and trip its one-runtime

livekit-net/Cargo.toml

@@ -25,6 +25,9 @@ pub use types::{Header, HttpResponse, TransportError};
 
 use std::sync::{Arc, OnceLock};
 
+#[cfg(feature = "uniffi")]
+uniffi::setup_scaffolding!();
+
 /// Render a URL for logging with secrets stripped: userinfo (`user:password@`)
 /// and the query string (which can carry an access token). Keeps scheme, host,
 /// port, and path.
@@ -45,12 +48,14 @@ static HTTP: OnceLock<Arc<dyn HttpClient>> = OnceLock::new();
 ///
 /// Independent of [`set_http_client`]: a consumer that only needs HTTP (e.g. a
 /// token source) can register that alone, and vice versa.
+#[cfg_attr(feature = "uniffi", uniffi::export)]
 pub fn set_ws_client(c: Arc<dyn WsClient>) {
     let _ = WS.set(c);
 }
 
 /// Register the process-wide HTTP client. Call once at startup, before the first
 /// request. A later call is ignored (first registration wins).
+#[cfg_attr(feature = "uniffi", uniffi::export)]
 pub fn set_http_client(c: Arc<dyn HttpClient>) {
     let _ = HTTP.set(c);
 }

livekit-net/src/lib.rs

@@ -17,6 +17,7 @@ use std::sync::Arc;
 
 /// A single open WebSocket connection. Control frames (ping/pong, close handshake)
 /// are the implementation's own responsibility; only binary application frames cross here.
+#[cfg_attr(feature = "uniffi", uniffi::export(with_foreign))]
 #[async_trait::async_trait]
 pub trait WsConnection: Send + Sync + 'static {
     /// Send one binary application frame.
@@ -31,12 +32,14 @@ pub trait WsConnection: Send + Sync + 'static {
 ///
 /// A record wrapper, not a bare `Arc<dyn WsConnection>`: uniffi 0.31 cannot
 /// lift a trait object returned from an async `with_foreign` method.
+#[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
 pub struct WsConnectResult {
     pub connection: Arc<dyn WsConnection>,
 }
 
 /// A host- or Rust-provided WebSocket transport. Opens the LiveKit signalling
 /// WebSocket; knows nothing about LiveKit/protobuf.
+#[cfg_attr(feature = "uniffi", uniffi::export(with_foreign))]
 #[async_trait::async_trait]
 pub trait WsClient: Send + Sync {
     /// Open a WebSocket. `url` is the full ws(s):// URL including query string.
@@ -51,6 +54,7 @@ pub trait WsClient: Send + Sync {
 }
 
 /// The HTTP method for an [`HttpClient::request`].
+#[cfg_attr(feature = "uniffi", derive(uniffi::Enum))]
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum HttpMethod {
     Get,
@@ -64,6 +68,7 @@ pub enum HttpMethod {
 /// Implementors provide the single [`request`](HttpClient::request) primitive;
 /// [`HttpClientExt`] layers `get`/`post` on top, so adding verbs never widens the
 /// implementation (or, for foreign impls, the FFI) surface.
+#[cfg_attr(feature = "uniffi", uniffi::export(with_foreign))]
 #[async_trait::async_trait]
 pub trait HttpClient: Send + Sync {
     /// Perform one HTTP request, sending `body` if present.

livekit-net/src/transport.rs

@@ -15,13 +15,15 @@
 use std::fmt;
 
 /// A single HTTP/WebSocket request header.
+#[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
 #[derive(Debug, Clone)]
 pub struct Header {
     pub name: String,
     pub value: String,
 }
 
 /// The result of an HTTP request performed by the transport.
+#[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
 #[derive(Debug, Clone)]
 pub struct HttpResponse {
     pub status: u16,
@@ -31,6 +33,7 @@ pub struct HttpResponse {
 }
 
 /// Errors a transport implementation may return. Mapped onto `SignalError` by the caller.
+#[cfg_attr(feature = "uniffi", derive(uniffi::Error))]
 #[derive(Debug, Clone)]
 pub enum TransportError {
     Timeout,

livekit-net/src/types.rs

@@ -15,6 +15,7 @@ publish = false
 livekit-protocol = { workspace = true }
 livekit-api = { workspace = true, default-features = false, features = ["access-token"] }
 livekit-datatrack = { workspace = true, features = ["uniffi"] }
+livekit-net = { workspace = true, features = ["uniffi"] }
 uniffi = { workspace = true, features = ["scaffolding-ffi-buffer-fns", "tokio"] }
 log = { workspace = true }
 tokio = { workspace = true, features = ["sync", "rt-multi-thread"] }

livekit-uniffi/Cargo.toml

@@ -30,4 +30,6 @@ pub mod common;
 /// Global async runtime.
 pub mod runtime;
 
+extern crate livekit_net;
+
 uniffi::setup_scaffolding!();