vouch/metrics.go

99 lines
2.5 KiB
Go

// Copyright © 2021 Attestant Limited.
// 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 main
import (
"context"
"github.com/attestantio/vouch/services/metrics"
"github.com/pkg/errors"
"github.com/prometheus/client_golang/prometheus"
)
var metricsNamespace = "vouch"
var releaseMetric *prometheus.GaugeVec
var readyMetric prometheus.Gauge
func registerMetrics(ctx context.Context, monitor metrics.Service) error {
if releaseMetric != nil {
// Already registered.
return nil
}
if monitor == nil {
// No monitor.
return nil
}
switch monitor.Presenter() {
case "prometheus":
return registerPrometheusMetrics(ctx)
case "null":
log.Debug().Msg("no metrics will be generated for this module")
}
return nil
}
func registerPrometheusMetrics(ctx context.Context) error {
startTime := prometheus.NewGauge(prometheus.GaugeOpts{
Namespace: metricsNamespace,
Name: "start_time_secs",
Help: "The timestamp at which this instance started.",
})
if err := prometheus.Register(startTime); err != nil {
return errors.Wrap(err, "failed to regsiter start_time_secs")
}
startTime.SetToCurrentTime()
releaseMetric = prometheus.NewGaugeVec(prometheus.GaugeOpts{
Namespace: metricsNamespace,
Name: "release",
Help: "The release of this instance.",
}, []string{"version"})
if err := prometheus.Register(releaseMetric); err != nil {
return err
}
readyMetric = prometheus.NewGauge(prometheus.GaugeOpts{
Namespace: metricsNamespace,
Name: "ready",
Help: "1 if ready to serve requests, otherwise 0.",
})
if err := prometheus.Register(readyMetric); err != nil {
return errors.Wrap(err, "failed to regsiter ready")
}
return nil
}
// SetRelease is called when the release version is established.
func setRelease(ctx context.Context, version string) {
if releaseMetric == nil {
return
}
releaseMetric.WithLabelValues(version).Set(1)
}
func setReady(ctx context.Context, ready bool) {
if readyMetric == nil {
return
}
if ready {
readyMetric.Set(1)
} else {
readyMetric.Set(0)
}
}