boulder/rocsp/metrics.go

49 lines
1.6 KiB
Go

package rocsp
import (
"github.com/go-redis/redis/v8"
"github.com/prometheus/client_golang/prometheus"
)
type metricsCollector struct {
rdb *redis.ClusterClient
// Stats accessible from the go-redis connector:
// https://pkg.go.dev/github.com/go-redis/redis@v6.15.9+incompatible/internal/pool#Stats
hits *prometheus.Desc
misses *prometheus.Desc
timeouts *prometheus.Desc
totalConns *prometheus.Desc
idleConns *prometheus.Desc
staleConns *prometheus.Desc
}
// Describe is implemented with DescribeByCollect. That's possible because the
// Collect method will always return the same metrics with the same descriptors.
func (dbc metricsCollector) Describe(ch chan<- *prometheus.Desc) {
prometheus.DescribeByCollect(dbc, ch)
}
// Collect first triggers the Redis ClusterClient's PoolStats function.
// Then it creates constant metrics for each Stats value on the fly based
// on the returned data.
//
// Note that Collect could be called concurrently, so we depend on PoolStats()
// to be concurrency-safe.
func (dbc metricsCollector) Collect(ch chan<- prometheus.Metric) {
writeStat := func(stat *prometheus.Desc, typ prometheus.ValueType, val float64) {
ch <- prometheus.MustNewConstMetric(stat, typ, val)
}
writeGauge := func(stat *prometheus.Desc, val float64) {
writeStat(stat, prometheus.GaugeValue, val)
}
stats := dbc.rdb.PoolStats()
writeGauge(dbc.hits, float64(stats.Hits))
writeGauge(dbc.misses, float64(stats.Misses))
writeGauge(dbc.timeouts, float64(stats.Timeouts))
writeGauge(dbc.totalConns, float64(stats.TotalConns))
writeGauge(dbc.idleConns, float64(stats.IdleConns))
writeGauge(dbc.staleConns, float64(stats.StaleConns))
}