add an option for the TCP connection timeout

tcp.go

@@ -21,9 +21,7 @@ import (
 	manet "github.com/multiformats/go-multiaddr/net"
 )
 
-// DefaultConnectTimeout is the (default) maximum amount of time the TCP
-// transport will spend on the initial TCP connect before giving up.
-var DefaultConnectTimeout = 5 * time.Second
+const defaultConnectTimeout = 5 * time.Second
 
 var log = logging.Logger("tcp-tpt")
 
@@ -97,6 +95,12 @@ func DisableReuseport() Option {
 		return nil
 	}
 }
+func WithConnectionTimeout(d time.Duration) Option {
+	return func(tr *TcpTransport) error {
+		tr.connectTimeout = d
+		return nil
+	}
+}
 
 // TcpTransport is the TCP transport.
 type TcpTransport struct {
@@ -108,7 +112,7 @@ type TcpTransport struct {
 	disableReuseport bool
 
 	// TCP connect timeout
-	ConnectTimeout time.Duration
+	connectTimeout time.Duration
 
 	reuse rtpt.Transport
 }
@@ -118,7 +122,10 @@ var _ transport.Transport = &TcpTransport{}
 // NewTCPTransport creates a tcp transport object that tracks dialers and listeners
 // created. It represents an entire TCP stack (though it might not necessarily be).
 func NewTCPTransport(upgrader *tptu.Upgrader, opts ...Option) (*TcpTransport, error) {
-	tr := &TcpTransport{Upgrader: upgrader, ConnectTimeout: DefaultConnectTimeout}
+	tr := &TcpTransport{
+		Upgrader:       upgrader,
+		connectTimeout: defaultConnectTimeout, // can be set by using the WithConnectionTimeout option
+	}
 	for _, o := range opts {
 		if err := o(tr); err != nil {
 			return nil, err
@@ -137,9 +144,9 @@ func (t *TcpTransport) CanDial(addr ma.Multiaddr) bool {
 
 func (t *TcpTransport) maDial(ctx context.Context, raddr ma.Multiaddr) (manet.Conn, error) {
 	// Apply the deadline iff applicable
-	if t.ConnectTimeout > 0 {
+	if t.connectTimeout > 0 {
 		var cancel context.CancelFunc
-		ctx, cancel = context.WithTimeout(ctx, t.ConnectTimeout)
+		ctx, cancel = context.WithTimeout(ctx, t.connectTimeout)
 		defer cancel()
 	}