feat: sprout-pair-relay — ephemeral sidecar for NIP-AB device pairing (#467)

Cargo.lock

@@ -3837,6 +3837,24 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "sprout-pair-relay"
+version = "0.1.0"
+dependencies = [
+ "futures-util",
+ "http-body-util",
+ "hyper",
+ "hyper-util",
+ "parking_lot",
+ "rand 0.8.5",
+ "secp256k1",
+ "serde_json",
+ "sha2 0.10.9",
+ "tokio",
+ "tokio-tungstenite",
+ "tokio-util",
+]
+
 [[package]]
 name = "sprout-pairing-cli"
 version = "0.1.0"

Cargo.toml

@@ -20,6 +20,7 @@ members = [
     "crates/sprout-persona",
     "crates/git-credential-nostr",
     "crates/git-sign-nostr",
+    "crates/sprout-pair-relay",
 ]
 exclude = ["desktop/src-tauri"]
 resolver = "2"

crates/sprout-pair-relay/Cargo.toml

@@ -0,0 +1,36 @@
+[package]
+name        = "sprout-pair-relay"
+description = "Ephemeral sidecar relay for NIP-AB device pairing handshakes"
+version.workspace     = true
+edition.workspace     = true
+rust-version.workspace = true
+license.workspace     = true
+repository.workspace  = true
+
+[lib]
+name = "sprout_pair_relay"
+path = "src/lib.rs"
+
+[[bin]]
+name = "sprout-pair-relay"
+path = "src/main.rs"
+
+[dependencies]
+tokio            = { workspace = true, features = ["rt-multi-thread", "macros", "net", "time", "sync"] }
+tokio-tungstenite = { workspace = true }
+serde_json       = { workspace = true }
+futures-util     = { workspace = true }
+tokio-util       = { workspace = true }
+parking_lot      = "0.12"
+hyper            = { version = "1", features = ["server", "http1"] }
+hyper-util       = { version = "0.1", features = ["tokio"] }
+http-body-util   = "0.1"
+secp256k1        = { version = "0.29", features = ["global-context"] }
+sha2             = "0.10"
+
+[dev-dependencies]
+tokio            = { workspace = true, features = ["test-util"] }
+tokio-tungstenite = { workspace = true }
+secp256k1        = { version = "0.29", features = ["global-context", "rand-std"] }
+sha2             = "0.10"
+rand             = "0.8"

crates/sprout-pair-relay/src/main.rs

@@ -0,0 +1,19 @@
+use std::net::SocketAddr;
+use std::sync::Arc;
+
+use sprout_pair_relay::{run_server, Relay};
+use tokio::net::TcpListener;
+
+#[tokio::main]
+async fn main() {
+    let addr: SocketAddr = ([127, 0, 0, 1], 5000).into();
+    let listener = match TcpListener::bind(addr).await {
+        Ok(l) => l,
+        Err(e) => {
+            eprintln!("fatal: failed to bind {addr}: {e}");
+            std::process::exit(1);
+        }
+    };
+    let relay = Arc::new(Relay::new());
+    run_server(listener, relay).await;
+}