metrics: add chain error counter

chain/chain.go

@@ -5,9 +5,17 @@ type Chainer interface {
 }
 
 type Chain struct {
+	name   string
 	groups []*NodeGroup
 }
 
+func NewChain(name string, groups ...*NodeGroup) *Chain {
+	return &Chain{
+		name:   name,
+		groups: groups,
+	}
+}
+
 func (c *Chain) AddNodeGroup(group *NodeGroup) {
 	c.groups = append(c.groups, group)
 }
@@ -17,7 +25,9 @@ func (c *Chain) Route(network, address string) (r *Route) {
 		return
 	}
 
-	r = &Route{}
+	r = &Route{
+		chain: c,
+	}
 	for _, group := range c.groups {
 		node := group.Next()
 		if node == nil {

chain/route.go

@@ -11,6 +11,7 @@ import (
 	"github.com/go-gost/core/common/util/udp"
 	"github.com/go-gost/core/connector"
 	"github.com/go-gost/core/logger"
+	"github.com/go-gost/core/metrics"
 )
 
 var (
@@ -18,8 +19,9 @@ var (
 )
 
 type Route struct {
-	nodes    []*Node
+	chain    *Chain
 	ifceName string
+	nodes    []*Node
 	logger   logger.Logger
 }
 
@@ -75,6 +77,12 @@ func (r *Route) connect(ctx context.Context) (conn net.Conn, err error) {
 		return nil, ErrEmptyRoute
 	}
 
+	defer func() {
+		if err != nil && r.chain != nil {
+			metrics.ChainErrors(r.chain.name).Inc()
+		}
+	}()
+
 	network := "ip"
 	node := r.nodes[0]
 

metrics/metrics.go

@@ -39,6 +39,7 @@ type Metrics struct {
 	inputBytes       *prometheus.CounterVec
 	outputBytes      *prometheus.CounterVec
 	handlerErrors    *prometheus.CounterVec
+	chainErrors      *prometheus.CounterVec
 }
 
 func NewMetrics() *Metrics {
@@ -93,6 +94,12 @@ func NewMetrics() *Metrics {
 				Help: "Total service handler errors",
 			},
 			[]string{"host", "service"}),
+		chainErrors: prometheus.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "gost_chain_errors_total",
+				Help: "Total chain errors",
+			},
+			[]string{"host", "chain"}),
 	}
 	prometheus.MustRegister(m.services)
 	prometheus.MustRegister(m.requests)
@@ -101,6 +108,7 @@ func NewMetrics() *Metrics {
 	prometheus.MustRegister(m.inputBytes)
 	prometheus.MustRegister(m.outputBytes)
 	prometheus.MustRegister(m.handlerErrors)
+	prometheus.MustRegister(m.chainErrors)
 	return m
 }
 
@@ -180,3 +188,14 @@ func HandlerErrors(service string) Counter {
 			"service": service,
 		})
 }
+
+func ChainErrors(chain string) Counter {
+	if metrics == nil || metrics.chainErrors == nil {
+		return nilCounter
+	}
+	return metrics.chainErrors.
+		With(prometheus.Labels{
+			"host":  metrics.host,
+			"chain": chain,
+		})
+}