context option for simultaneous connect

Author: vyzo

network/context.go

@@ -14,10 +14,12 @@ type noDialCtxKey struct{}
 type dialPeerTimeoutCtxKey struct{}
 type forceDirectDialCtxKey struct{}
 type useTransientCtxKey struct{}
+type simConnectCtxKey struct{}
 
 var noDial = noDialCtxKey{}
 var forceDirectDial = forceDirectDialCtxKey{}
 var useTransient = useTransientCtxKey{}
+var simConnect = simConnectCtxKey{}
 
 // EXPERIMENTAL
 // WithForceDirectDial constructs a new context with an option that instructs the network
@@ -37,6 +39,24 @@ func GetForceDirectDial(ctx context.Context) (forceDirect bool, reason string) {
 	return false, ""
 }
 
+// EXPERIMENTAL
+// WithSimultaneousConnect constructs a new context with an option that instructs the transport
+// to apply hole punching logic where applicable.
+func WithSimultaneousConnect(ctx context.Context, reason string) context.Context {
+	return context.WithValue(ctx, simConnect, reason)
+}
+
+// EXPERIMENTAL
+// GetSimultaneousConnect returns true if the simultaneous connect option is set in the context
+func GetSimultaneousConnect(ctx context.Context) (simconnect bool, reason string) {
+	v := ctx.Value(simConnect)
+	if v != nil {
+		return true, v.(string)
+	}
+
+	return false, ""
+}
+
 // WithNoDial constructs a new context with an option that instructs the network
 // to not attempt a new dial when opening a stream.
 func WithNoDial(ctx context.Context, reason string) context.Context {