[#179] Expose pool metrics

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

app.go

@@ -165,7 +165,7 @@ func newApp(ctx context.Context, opt ...Option) App {
 	}
 
 	if a.cfg.GetBool(cfgPrometheusEnabled) {
-		a.metrics = metrics.NewGateMetrics()
+		a.metrics = metrics.NewGateMetrics(a.pool)
 	}
 
 	return a

metrics/metrics.go

@@ -3,6 +3,7 @@ package metrics
 import (
 	"net/http"
 
+	"github.com/nspcc-dev/neofs-sdk-go/pool"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.uber.org/zap"
@@ -11,23 +12,54 @@ import (
 const (
 	namespace      = "neofs_http_gw"
 	stateSubsystem = "state"
+	poolSubsystem  = "pool"
+
+	methodGetBalance       = "get_balance"
+	methodPutContainer     = "put_container"
+	methodGetContainer     = "get_container"
+	methodListContainer    = "list_container"
+	methodDeleteContainer  = "delete_container"
+	methodGetContainerEacl = "get_container_eacl"
+	methodSetContainerEacl = "set_container_eacl"
+	methodEndpointInfo     = "endpoint_info"
+	methodNetworkInfo      = "network_info"
+	methodPutObject        = "put_object"
+	methodDeleteObject     = "delete_object"
+	methodGetObject        = "get_object"
+	methodHeadObject       = "head_object"
+	methodRangeObject      = "range_object"
+	methodCreateSession    = "create_session"
 )
 
 type GateMetrics struct {
 	stateMetrics
+	poolMetricsCollector
 }
 
 type stateMetrics struct {
 	healthCheck prometheus.Gauge
 }
 
+type poolMetricsCollector struct {
+	pool                *pool.Pool
+	overallErrors       prometheus.Counter
+	overallNodeErrors   *prometheus.CounterVec
+	overallNodeRequests *prometheus.CounterVec
+	currentErrors       *prometheus.GaugeVec
+	requestDuration     *prometheus.GaugeVec
+}
+
 // NewGateMetrics creates new metrics for http gate.
-func NewGateMetrics() *GateMetrics {
+func NewGateMetrics(p *pool.Pool) *GateMetrics {
 	stateMetric := newStateMetrics()
 	stateMetric.register()
 
+	poolMetric := newPoolMetricsCollector(p)
+	poolMetric.register()
+
 	return &GateMetrics{
-		stateMetrics: *stateMetric,
+		stateMetrics:         *stateMetric,
+		poolMetricsCollector: *poolMetric,
 	}
 }
 
@@ -50,6 +82,131 @@ func (m stateMetrics) SetHealth(s int32) {
 	m.healthCheck.Set(float64(s))
 }
 
+func newPoolMetricsCollector(p *pool.Pool) *poolMetricsCollector {
+	overallErrors := prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: poolSubsystem,
+			Name:      "overall_errors",
+			Help:      "Total number of errors in pool",
+		},
+	)
+
+	overallNodeErrors := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: poolSubsystem,
+			Name:      "overall_node_errors",
+			Help:      "Total number of errors for connection in pool",
+		},
+		[]string{
+			"node",
+		},
+	)
+
+	overallNodeRequests := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: poolSubsystem,
+			Name:      "overall_node_requests",
+			Help:      "Total number of requests to specific node in pool",
+		},
+		[]string{
+			"node",
+		},
+	)
+
+	currentErrors := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: namespace,
+			Subsystem: poolSubsystem,
+			Name:      "current_errors",
+			Help:      "Number of errors on current connections that will be reset after the threshold",
+		},
+		[]string{
+			"node",
+		},
+	)
+
+	requestsDuration := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: namespace,
+			Subsystem: poolSubsystem,
+			Name:      "avg_request_duration",
+			Help:      "Average request duration (in milliseconds) for specific method on node in pool",
+		},
+		[]string{
+			"node",
+			"method",
+		},
+	)
+
+	return &poolMetricsCollector{
+		pool:                p,
+		overallErrors:       overallErrors,
+		overallNodeErrors:   overallNodeErrors,
+		overallNodeRequests: overallNodeRequests,
+		currentErrors:       currentErrors,
+		requestDuration:     requestsDuration,
+	}
+}
+
+func (m *poolMetricsCollector) Collect(ch chan<- prometheus.Metric) {
+	m.updateStatistic()
+	m.overallErrors.Collect(ch)
+	m.overallNodeErrors.Collect(ch)
+	m.overallNodeRequests.Collect(ch)
+	m.currentErrors.Collect(ch)
+	m.requestDuration.Collect(ch)
+}
+
+func (m poolMetricsCollector) Describe(descs chan<- *prometheus.Desc) {
+	m.overallErrors.Describe(descs)
+	m.overallNodeErrors.Describe(descs)
+	m.overallNodeRequests.Describe(descs)
+	m.currentErrors.Describe(descs)
+	m.requestDuration.Describe(descs)
+}
+
+func (m *poolMetricsCollector) register() {
+	prometheus.MustRegister(m)
+}
+
+func (m *poolMetricsCollector) updateStatistic() {
+	stat := m.pool.Statistic()
+
+	m.currentErrors.Reset()
+	m.requestDuration.Reset()
+
+	for _, node := range stat.Nodes() {
+		m.overallNodeErrors.WithLabelValues(node.Address()).Add(float64(node.OverallErrors()))
+		m.overallNodeRequests.WithLabelValues(node.Address()).Add(float64(node.Requests()))
+
+		m.currentErrors.WithLabelValues(node.Address()).Set(float64(node.CurrentErrors()))
+		m.updateRequestsDuration(node)
+	}
+
+	m.overallErrors.Add(float64(stat.OverallErrors()))
+}
+
+func (m *poolMetricsCollector) updateRequestsDuration(node pool.NodeStatistic) {
+	m.requestDuration.WithLabelValues(node.Address(), methodGetBalance).Set(float64(node.AverageGetBalance().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodPutContainer).Set(float64(node.AveragePutContainer().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodGetContainer).Set(float64(node.AverageGetContainer().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodListContainer).Set(float64(node.AverageListContainer().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodDeleteContainer).Set(float64(node.AverageDeleteContainer().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodGetContainerEacl).Set(float64(node.AverageGetContainerEACL().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodSetContainerEacl).Set(float64(node.AverageSetContainerEACL().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodEndpointInfo).Set(float64(node.AverageEndpointInfo().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodNetworkInfo).Set(float64(node.AverageNetworkInfo().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodPutObject).Set(float64(node.AveragePutObject().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodDeleteObject).Set(float64(node.AverageDeleteObject().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodGetObject).Set(float64(node.AverageGetObject().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodHeadObject).Set(float64(node.AverageHeadObject().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodRangeObject).Set(float64(node.AverageRangeObject().Milliseconds()))
+	m.requestDuration.WithLabelValues(node.Address(), methodCreateSession).Set(float64(node.AverageCreateSession().Milliseconds()))
+}
+
 // NewPrometheusService creates a new service for gathering prometheus metrics.
 func NewPrometheusService(log *zap.Logger, cfg Config) *Service {
 	if log == nil {