add tls and ws listener

client/dialer/dialer.go

@@ -0,0 +1,20 @@
+package dialer
+
+import (
+	"context"
+	"net"
+)
+
+// Dialer dials to target server.
+type Dialer interface {
+	Init(md Metadata) error
+	Dial(ctx context.Context, addr string) (net.Conn, error)
+}
+
+type Handshaker interface {
+	Handshake(ctx context.Context, conn net.Conn) (net.Conn, error)
+}
+
+type Multiplexer interface {
+	Multiplexed() bool
+}