improve chain node bypass

chain/chain.go

@@ -29,14 +29,15 @@ func (c *Chain) Route(network, address string) (r *Route) {
 		chain: c,
 	}
 	for _, group := range c.groups {
-		node := group.Next()
-		if node == nil {
-			return
-		}
-		if node.Bypass != nil && node.Bypass.Contains(address) {
+		// hop level bypass test
+		if group.bypass != nil && group.bypass.Contains(address) {
 			break
 		}
 
+		node := group.filter(address).Next()
+		if node == nil {
+			return
+		}
 		if node.Transport.Multiplex() {
 			tr := node.Transport.Copy().
 				WithRoute(r)

chain/node.go

@@ -28,6 +28,7 @@ func (node *Node) Copy() *Node {
 type NodeGroup struct {
 	nodes    []*Node
 	selector Selector
+	bypass   bypass.Bypass
 }
 
 func NewNodeGroup(nodes ...*Node) *NodeGroup {
@@ -45,6 +46,25 @@ func (g *NodeGroup) WithSelector(selector Selector) *NodeGroup {
 	return g
 }
 
+func (g *NodeGroup) WithBypass(bypass bypass.Bypass) *NodeGroup {
+	g.bypass = bypass
+	return g
+}
+
+func (g *NodeGroup) filter(addr string) *NodeGroup {
+	var nodes []*Node
+	for _, node := range g.nodes {
+		if node.Bypass == nil || !node.Bypass.Contains(addr) {
+			nodes = append(nodes, node)
+		}
+	}
+	return &NodeGroup{
+		nodes:    nodes,
+		selector: g.selector,
+		bypass:   g.bypass,
+	}
+}
+
 func (g *NodeGroup) Next() *Node {
 	if g == nil || len(g.nodes) == 0 {
 		return nil