63 lines
1.7 KiB
Go
63 lines
1.7 KiB
Go
package rushlink
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import (
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"log"
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"net/http"
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"time"
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"gitea.hashru.nl/dsprenkels/rushlink/internal/db"
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"github.com/gorilla/mux"
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"github.com/pkg/errors"
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/client_golang/prometheus/promhttp"
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bolt "go.etcd.io/bbolt"
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)
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const metricNamespace = "rushlink"
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var metricRequestsTotalCounter = prometheus.NewCounterVec(prometheus.CounterOpts{
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Namespace: metricNamespace,
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Subsystem: "http",
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Name: "requests_total",
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Help: "How many HTTP requests processed, partitioned by status code and HTTP method.",
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}, []string{"code", "method"})
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func metricURLsTotal(database *db.Database) float64 {
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var metric float64
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if err := database.Bolt.View(func(tx *bolt.Tx) error {
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bucket := tx.Bucket([]byte("pastes"))
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if bucket == nil {
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return errors.New("bucket 'pastes' could not be found")
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}
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metric = float64(bucket.Stats().KeyN)
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return nil
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}); err != nil {
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log.Printf("error: %v", errors.Wrap(err, "fetching pastes_total metric"))
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return 0
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}
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return metric
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}
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// StartMetricsServer starts sering Prometheus metrics exports on addr
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func StartMetricsServer(addr string, database *db.Database, fs *db.FileStore) {
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prometheus.MustRegister(metricRequestsTotalCounter)
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prometheus.MustRegister(prometheus.NewGaugeFunc(prometheus.GaugeOpts{
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Namespace: metricNamespace,
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Subsystem: "pastes",
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Name: "urls_total",
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Help: "The current amount of pastes in the database.",
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}, func() float64 { return metricURLsTotal(database) }))
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router := mux.NewRouter()
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router.Handle("/metrics", promhttp.Handler()).Methods("GET")
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srv := &http.Server{
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Handler: router,
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Addr: addr,
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WriteTimeout: 15 * time.Second,
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ReadTimeout: 15 * time.Second,
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}
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log.Fatal(srv.ListenAndServe())
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}
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