add chain

pkg/chain/node.go

@@ -0,0 +1,59 @@
+package chain
+
+type Node struct {
+	name      string
+	addr      string
+	transport *Transport
+}
+
+func NewNode(name, addr string) *Node {
+	return &Node{
+		name: name,
+		addr: addr,
+	}
+}
+
+func (node *Node) Name() string {
+	return node.name
+}
+
+func (node *Node) Addr() string {
+	return node.addr
+}
+
+func (node *Node) Transport() *Transport {
+	return node.transport
+}
+
+func (node *Node) WithTransport(tr *Transport) *Node {
+	node.transport = tr
+	return node
+}
+
+type NodeGroup struct {
+	nodes    []*Node
+	selector Selector
+}
+
+func NewNodeGroup(nodes ...*Node) *NodeGroup {
+	return &NodeGroup{
+		nodes: nodes,
+	}
+}
+
+func (g *NodeGroup) AddNode(node *Node) {
+	g.nodes = append(g.nodes, node)
+}
+
+func (g *NodeGroup) WithSelector(selector Selector) {
+	g.selector = selector
+}
+
+func (g *NodeGroup) Next() *Node {
+	selector := g.selector
+	if selector == nil {
+		// selector = defaultSelector
+		return g.nodes[0]
+	}
+	return selector.Select(g.nodes...)
+}