feat(libp2p): deprecate mplex

`mplex` module (no flow control and no streams limit) is deprecated to encourage `yamux` usage.

Resolves libp2p#3677.

Pull-Request: libp2p#3689.

examples/chat-example/Cargo.toml

@@ -10,5 +10,5 @@ async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 env_logger = "0.10.0"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "gossipsub", "mdns", "mplex", "noise", "macros", "tcp", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "gossipsub", "mdns", "noise", "macros", "tcp", "yamux"] }
 libp2p-quic = { path = "../../transports/quic", features = ["async-std"] }

examples/dcutr/Cargo.toml

@@ -10,5 +10,5 @@ clap = { version = "4.2.1", features = ["derive"] }
 env_logger = "0.10.0"
 futures = "0.3.28"
 futures-timer = "3.0"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "dcutr", "identify", "macros", "mplex", "noise", "ping", "relay", "rendezvous", "tcp", "tokio", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "dcutr", "identify", "macros", "noise", "ping", "relay", "rendezvous", "tcp", "tokio", "yamux"] }
 log = "0.4"

examples/distributed-key-value-store/Cargo.toml

@@ -10,5 +10,5 @@ async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 env_logger = "0.10"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad", "mdns", "mplex", "noise", "macros", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad", "mdns", "noise", "macros", "tcp", "websocket", "yamux"] }
 multiaddr = { version = "0.17.0" }

examples/file-sharing/Cargo.toml

@@ -12,5 +12,5 @@ clap = { version = "4.2.1", features = ["derive"] }
 either = "1.8"
 env_logger = "0.10"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad",  "mplex", "noise", "macros", "request-response", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad", "noise", "macros", "request-response", "tcp", "websocket", "yamux"] }
 multiaddr = { version = "0.17.0" }

examples/identify/Cargo.toml

@@ -9,4 +9,4 @@ license = "MIT"
 async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "dcutr", "identify", "macros", "mplex", "noise", "ping", "relay", "rendezvous", "tcp", "tokio", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "dcutr", "identify", "macros", "noise", "ping", "relay", "rendezvous", "tcp", "tokio", "yamux"] }

examples/ipfs-kad/Cargo.toml

@@ -10,4 +10,4 @@ async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 env_logger = "0.10"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad",  "mplex", "noise", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "kad", "mplex", "noise", "tcp", "websocket", "yamux"] }

examples/ipfs-private/Cargo.toml

@@ -11,5 +11,5 @@ async-trait = "0.1"
 either = "1.8"
 env_logger = "0.10"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "gossipsub", "dns", "identify", "kad", "macros", "mplex", "noise", "ping", "pnet", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "gossipsub", "dns", "identify", "kad", "macros", "noise", "ping", "pnet", "tcp", "websocket", "yamux"] }
 multiaddr = { version = "0.17.0" }

examples/ping-example/Cargo.toml

@@ -9,5 +9,5 @@ license = "MIT"
 async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "dns", "macros", "mplex", "noise", "ping", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "dns", "macros", "noise", "ping", "tcp", "websocket", "yamux"] }
 multiaddr = { version = "0.17.0" }

examples/rendezvous/Cargo.toml

@@ -10,6 +10,6 @@ async-std = { version = "1.12", features = ["attributes"] }
 async-trait = "0.1"
 env_logger = "0.10.0"
 futures = "0.3.28"
-libp2p = { path = "../../libp2p", features = ["async-std", "identify", "macros", "mplex", "noise", "ping", "rendezvous", "tcp", "tokio", "yamux"] }
+libp2p = { path = "../../libp2p", features = ["async-std", "identify", "macros", "noise", "ping", "rendezvous", "tcp", "tokio", "yamux"] }
 log = "0.4"
 tokio = { version = "1.25", features = [ "rt-multi-thread", "macros", "time" ] }

interop-tests/Cargo.toml

@@ -10,9 +10,10 @@ anyhow = "1"
 either = "1.8.0"
 env_logger = "0.10.0"
 futures = "0.3.28"
-libp2p = { path = "../libp2p", features = ["websocket", "mplex", "yamux", "tcp", "tokio", "ping", "noise", "tls", "dns", "rsa", "macros"] }
+libp2p = { path = "../libp2p", features = ["websocket", "yamux", "tcp", "tokio", "ping", "noise", "tls", "dns", "rsa", "macros"] }
 libp2p-quic = { path = "../transports/quic", features = ["tokio"] }
 libp2p-webrtc = { path = "../transports/webrtc", features = ["tokio"] }
+libp2p-mplex = { path = "../muxers/mplex" }
 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 +13,10 @@ use libp2p::swarm::{keep_alive, NetworkBehaviour, SwarmEvent};
 use libp2p::tls::TlsStream;
 use libp2p::websocket::WsConfig;
 use libp2p::{
-    identity, mplex, noise, ping, swarm::SwarmBuilder, tcp, tls, yamux, InboundUpgradeExt,
-    Multiaddr, OutboundUpgradeExt, PeerId, Transport as _,
+    identity, noise, ping, swarm::SwarmBuilder, tcp, tls, yamux, InboundUpgradeExt, Multiaddr,
+    OutboundUpgradeExt, PeerId, Transport as _,
 };
+use libp2p_mplex as mplex;
 use libp2p_quic as quic;
 use libp2p_webrtc as webrtc;
 use redis::AsyncCommands;

libp2p/CHANGELOG.md

@@ -1,3 +1,11 @@
+## 0.51.3 - unreleased
+
+- Deprecate the `mplex` feature.
+The recommended baseline stream multiplexer is `yamux`.
+See [PR 3689].
+
+[PR 3689]: https://github.com/libp2p/rust-libp2p/pull/3689
+
 ## 0.51.2
 
 - Introduce `libp2p::connection_limits` module.

libp2p/Cargo.toml

@@ -3,7 +3,7 @@ name = "libp2p"
 edition = "2021"
 rust-version = "1.65.0"
 description = "Peer-to-peer networking library"
-version = "0.51.2"
+version = "0.51.3"
 authors = ["Parity Technologies <admin@parity.io>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"

libp2p/src/lib.rs

@@ -83,8 +83,12 @@ pub use libp2p_mdns as mdns;
 #[doc(inline)]
 pub use libp2p_metrics as metrics;
 #[cfg(feature = "mplex")]
-#[doc(inline)]
-pub use libp2p_mplex as mplex;
+#[deprecated(
+    note = "`mplex` is not recommended anymore. Please use `yamux` instead or depend on `libp2p-mplex` directly if you need it for legacy use cases."
+)]
+pub mod mplex {
+    pub use libp2p_mplex::*;
+}
 #[cfg(feature = "noise")]
 #[doc(inline)]
 pub use libp2p_noise as noise;
@@ -228,6 +232,7 @@ pub async fn development_transport(
         .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
         .multiplex(core::upgrade::SelectUpgrade::new(
             yamux::YamuxConfig::default(),
+            #[allow(deprecated)]
             mplex::MplexConfig::default(),
         ))
         .timeout(std::time::Duration::from_secs(20))
@@ -284,6 +289,7 @@ pub fn tokio_development_transport(
         .authenticate(noise::NoiseAuthenticated::xx(&keypair).unwrap())
         .multiplex(core::upgrade::SelectUpgrade::new(
             yamux::YamuxConfig::default(),
+            #[allow(deprecated)]
             mplex::MplexConfig::default(),
         ))
         .timeout(std::time::Duration::from_secs(20))