feat: deprecate webrtc and quic features in libp2p crate

We currently expose `libp2p-quic` and `libp2p-webrtc` as submodules from the `libp2p` crate despite those only being "alpha" status. This causes problems because we need to pin those dependencies due to `cargo` automatically upgrading alphas (which are allowed to incur breaking changes as per semver spec). Additionally, exposing these modules practically hides the "alpha" state of those modules, rendering it kind of obsolete.

The "alpha" state is still true for those modules, thus to properly communicate this to users, we deprecate the modules and require users to spell out the dependency and the alpha version in their manifest.

Pull-Request: libp2p#3580.

interop-tests/Cargo.toml

@@ -10,7 +10,9 @@ anyhow = "1"
 either = "1.8.0"
 env_logger = "0.10.0"
 futures = "0.3.27"
-libp2p = { path = "../libp2p", features = ["websocket", "quic",  "mplex", "yamux", "tcp", "tokio", "ping", "noise", "tls", "dns", "rsa", "macros", "webrtc"] }
+libp2p = { path = "../libp2p", features = ["websocket", "mplex", "yamux", "tcp", "tokio", "ping", "noise", "tls", "dns", "rsa", "macros"] }
+libp2p-quic = { path = "../transports/quic", features = ["tokio"] }
+libp2p-webrtc = { path = "../transports/webrtc", features = ["tokio"] }
 log = "0.4"
 rand = "0.8.5"
 redis = { version = "0.22.1", default-features = false, features = ["tokio-comp"] }

interop-tests/src/bin/ping.rs

@@ -13,9 +13,11 @@ use libp2p::swarm::{keep_alive, NetworkBehaviour, SwarmEvent};
 use libp2p::tls::TlsStream;
 use libp2p::websocket::WsConfig;
 use libp2p::{
-    identity, mplex, noise, ping, quic, swarm::SwarmBuilder, tcp, tls, webrtc, yamux,
-    InboundUpgradeExt, Multiaddr, OutboundUpgradeExt, PeerId, Transport as _,
+    identity, mplex, noise, ping, swarm::SwarmBuilder, tcp, tls, yamux, InboundUpgradeExt,
+    Multiaddr, OutboundUpgradeExt, PeerId, Transport as _,
 };
+use libp2p_quic as quic;
+use libp2p_webrtc as webrtc;
 use redis::AsyncCommands;
 
 #[tokio::main]

libp2p/CHANGELOG.md

@@ -3,7 +3,13 @@
 - Introduce `libp2p::connection_limits` module.
   See [PR 3386].
 
+- Deprecate the `quic` and `webrtc` feature.
+  These two crates are only in alpha state.
+  To properly communicate this to users, we want them to add the dependency directly which makes the `alpha` version visible.
+  See [PR 3580].
+
 [PR 3386]: https://github.com/libp2p/rust-libp2p/pull/3386
+[PR 3580]: https://github.com/libp2p/rust-libp2p/pull/3580
 
 # 0.51.1
 

libp2p/src/lib.rs

@@ -97,8 +97,12 @@ pub use libp2p_plaintext as plaintext;
 pub use libp2p_pnet as pnet;
 #[cfg(feature = "quic")]
 #[cfg(not(target_arch = "wasm32"))]
-#[doc(inline)]
-pub use libp2p_quic as quic;
+#[deprecated(
+    note = "`quic` is only in alpha status. Please depend on `libp2p-quic` directly and don't ues the `quic` feature of `libp2p`."
+)]
+pub mod quic {
+    pub use libp2p_quic::*;
+}
 #[cfg(feature = "relay")]
 #[doc(inline)]
 pub use libp2p_relay as relay;
@@ -131,8 +135,12 @@ pub use libp2p_wasm_ext as wasm_ext;
 #[cfg(feature = "webrtc")]
 #[cfg_attr(docsrs, doc(cfg(feature = "webrtc")))]
 #[cfg(not(target_arch = "wasm32"))]
-#[doc(inline)]
-pub use libp2p_webrtc as webrtc;
+#[deprecated(
+    note = "`webrtc` is only in alpha status. Please depend on `libp2p-webrtc` directly and don't ues the `webrtc` feature of `libp2p`."
+)]
+pub mod webrtc {
+    pub use libp2p_webrtc::*;
+}
 #[cfg(feature = "websocket")]
 #[cfg(not(target_arch = "wasm32"))]
 #[doc(inline)]