electrum: add support for Happy Eyeballs (RFC 8305)

Signed-off-by: Yuki Kishimoto <yukikishimoto@protonmail.com>

Author: yukibtc

Cargo.lock

@@ -20,6 +20,7 @@ bitcoin = "0.32"
 electrum_streaming_client = { git = "https://github.com/yukibtc/electrum_streaming_client", branch = "missing-features-req-patch", features = ["tokio"] }
 futures-util.workspace = true
 tokio = { workspace = true, features = ["macros", "net", "rt-multi-thread", "sync", "time"] }
+tokio-happy-eyeballs = "0.1"
 tokio-rustls = { version = "0.26", default-features = false, features = ["ring", "tls12"] }
 tokio-socks = { version =  "0.5", optional = true }
 tracing.workspace = true

tokio-electrum/Cargo.toml

@@ -1170,7 +1170,7 @@ async fn connect_tcp(
 
 async fn connect_direct_tcp(addr: &HostAndPort) -> Result<(BoxReadStream, BoxWriteStream), Error> {
     // Connect
-    let stream: TcpStream = TcpStream::connect(addr.to_string()).await?;
+    let stream: TcpStream = tokio_happy_eyeballs::connect(addr.to_string()).await?;
 
     // Split stream
     Ok(split_stream(stream))
@@ -1202,7 +1202,7 @@ async fn connect_ssl(
 
 async fn connect_direct_ssl(addr: &HostAndPort) -> Result<(BoxReadStream, BoxWriteStream), Error> {
     // Connect to the server
-    let tcp_stream: TcpStream = TcpStream::connect(addr.to_string()).await?;
+    let tcp_stream: TcpStream = tokio_happy_eyeballs::connect(addr.to_string()).await?;
 
     // Create TLS configuration
     ssl_connector(addr, tcp_stream).await