api: add missing metrics for API v2

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

api/api.go

@@ -126,6 +126,7 @@ func New(opts Options) (*API, error) {
 		opts.Silences,
 		opts.Peer,
 		log.With(l, "version", "v2"),
+		opts.Registry,
 	)
 
 	if err != nil {

api/metrics/metrics.go

@@ -0,0 +1,54 @@
+// Copyright 2019 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package metrics
+
+import "github.com/prometheus/client_golang/prometheus"
+
+// Alerts stores metrics for alerts which are common across all API versions.
+type Alerts struct {
+	firing   prometheus.Counter
+	resolved prometheus.Counter
+	invalid  prometheus.Counter
+}
+
+// NewAlerts returns an *Alerts struct for the given API version.
+func NewAlerts(version string, r prometheus.Registerer) *Alerts {
+	numReceivedAlerts := prometheus.NewCounterVec(prometheus.CounterOpts{
+		Name:        "alertmanager_alerts_received_total",
+		Help:        "The total number of received alerts.",
+		ConstLabels: prometheus.Labels{"version": version},
+	}, []string{"status"})
+	numInvalidAlerts := prometheus.NewCounter(prometheus.CounterOpts{
+		Name:        "alertmanager_alerts_invalid_total",
+		Help:        "The total number of received alerts that were invalid.",
+		ConstLabels: prometheus.Labels{"version": version},
+	})
+	if r != nil {
+		r.MustRegister(numReceivedAlerts, numInvalidAlerts)
+	}
+	return &Alerts{
+		firing:   numReceivedAlerts.WithLabelValues("firing"),
+		resolved: numReceivedAlerts.WithLabelValues("resolved"),
+		invalid:  numInvalidAlerts,
+	}
+}
+
+// Firing returns a counter of firing alerts.
+func (a *Alerts) Firing() prometheus.Counter { return a.firing }
+
+// Resolved returns a counter of resolved alerts.
+func (a *Alerts) Resolved() prometheus.Counter { return a.resolved }
+
+// Invalid returns a counter of invalid alerts.
+func (a *Alerts) Invalid() prometheus.Counter { return a.firing }

api/v1/api.go

@@ -31,6 +31,7 @@ import (
 	"github.com/prometheus/common/version"
 	"github.com/prometheus/prometheus/pkg/labels"
 
+	"github.com/prometheus/alertmanager/api/metrics"
 	"github.com/prometheus/alertmanager/cluster"
 	"github.com/prometheus/alertmanager/config"
 	"github.com/prometheus/alertmanager/dispatch"
@@ -74,9 +75,7 @@ type API struct {
 	uptime   time.Time
 	peer     *cluster.Peer
 	logger   log.Logger
-
-	numReceivedAlerts *prometheus.CounterVec
-	numInvalidAlerts  prometheus.Counter
+	m        *metrics.Alerts
 
 	getAlertStatus getAlertStatusFn
 
@@ -98,32 +97,14 @@ func New(
 		l = log.NewNopLogger()
 	}
 
-	numReceivedAlerts := prometheus.NewCounterVec(prometheus.CounterOpts{
-		Namespace: "alertmanager",
-		Name:      "alerts_received_total",
-		Help:      "The total number of received alerts.",
-	}, []string{"status"})
-
-	numInvalidAlerts := prometheus.NewCounter(prometheus.CounterOpts{
-		Namespace: "alertmanager",
-		Name:      "alerts_invalid_total",
-		Help:      "The total number of received alerts that were invalid.",
-	})
-	numReceivedAlerts.WithLabelValues("firing")
-	numReceivedAlerts.WithLabelValues("resolved")
-	if r != nil {
-		r.MustRegister(numReceivedAlerts, numInvalidAlerts)
-	}
-
 	return &API{
-		alerts:            alerts,
-		silences:          silences,
-		getAlertStatus:    sf,
-		uptime:            time.Now(),
-		peer:              peer,
-		logger:            l,
-		numReceivedAlerts: numReceivedAlerts,
-		numInvalidAlerts:  numInvalidAlerts,
+		alerts:         alerts,
+		silences:       silences,
+		getAlertStatus: sf,
+		uptime:         time.Now(),
+		peer:           peer,
+		logger:         l,
+		m:              metrics.NewAlerts("v1", r),
 	}
 }
 
@@ -450,9 +431,9 @@ func (api *API) insertAlerts(w http.ResponseWriter, r *http.Request, alerts ...*
 			alert.EndsAt = now.Add(resolveTimeout)
 		}
 		if alert.EndsAt.After(time.Now()) {
-			api.numReceivedAlerts.WithLabelValues("firing").Inc()
+			api.m.Firing().Inc()
 		} else {
-			api.numReceivedAlerts.WithLabelValues("resolved").Inc()
+			api.m.Resolved().Inc()
 		}
 	}
 
@@ -466,7 +447,7 @@ func (api *API) insertAlerts(w http.ResponseWriter, r *http.Request, alerts ...*
 
 		if err := a.Validate(); err != nil {
 			validationErrs.Add(err)
-			api.numInvalidAlerts.Inc()
+			api.m.Invalid().Inc()
 			continue
 		}
 		validAlerts = append(validAlerts, a)

api/v2/api.go

@@ -26,11 +26,13 @@ import (
 	"github.com/go-openapi/loads"
 	"github.com/go-openapi/runtime/middleware"
 	"github.com/go-openapi/strfmt"
+	"github.com/prometheus/client_golang/prometheus"
 	prometheus_model "github.com/prometheus/common/model"
 	"github.com/prometheus/common/version"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/rs/cors"
 
+	"github.com/prometheus/alertmanager/api/metrics"
 	open_api_models "github.com/prometheus/alertmanager/api/v2/models"
 	"github.com/prometheus/alertmanager/api/v2/restapi"
 	"github.com/prometheus/alertmanager/api/v2/restapi/operations"
@@ -67,6 +69,7 @@ type API struct {
 	setAlertStatus     setAlertStatusFn
 
 	logger log.Logger
+	m      *metrics.Alerts
 
 	Handler http.Handler
 }
@@ -83,6 +86,7 @@ func NewAPI(
 	silences *silence.Silences,
 	peer *cluster.Peer,
 	l log.Logger,
+	r prometheus.Registerer,
 ) (*API, error) {
 	api := API{
 		alerts:         alerts,
@@ -91,6 +95,7 @@ func NewAPI(
 		peer:           peer,
 		silences:       silences,
 		logger:         l,
+		m:              metrics.NewAlerts("v2", r),
 		uptime:         time.Now(),
 	}
 
@@ -302,12 +307,11 @@ func (api *API) postAlertsHandler(params alert_ops.PostAlertsParams) middleware.
 			alert.Timeout = true
 			alert.EndsAt = now.Add(resolveTimeout)
 		}
-		// TODO: Take care of the metrics endpoint
-		// if alert.EndsAt.After(time.Now()) {
-		// 	numReceivedAlerts.WithLabelValues("firing").Inc()
-		// } else {
-		// 	numReceivedAlerts.WithLabelValues("resolved").Inc()
-		// }
+		if alert.EndsAt.After(time.Now()) {
+			api.m.Firing().Inc()
+		} else {
+			api.m.Resolved().Inc()
+		}
 	}
 
 	// Make a best effort to insert all alerts that are valid.
@@ -320,7 +324,7 @@ func (api *API) postAlertsHandler(params alert_ops.PostAlertsParams) middleware.
 
 		if err := a.Validate(); err != nil {
 			validationErrs.Add(err)
-			// numInvalidAlerts.Inc()
+			api.m.Invalid().Inc()
 			continue
 		}
 		validAlerts = append(validAlerts, a)