Refactor database login into a separate module

metrics.go

@@ -5,6 +5,8 @@ import (
 	"net/http"
 	"time"
 
+	"gitea.hashru.nl/dsprenkels/rushlink/internal/db"
+
 	"github.com/gorilla/mux"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
@@ -13,7 +15,7 @@ import (
 	bolt "go.etcd.io/bbolt"
 )
 
-func StartMetricsServer(addr string) {
+func StartMetricsServer(addr string, db *db.Database) {
 	var (
 		_ = promauto.NewGaugeFunc(prometheus.GaugeOpts{
 			Namespace: "rushlink",
@@ -22,7 +24,7 @@ func StartMetricsServer(addr string) {
 			Help:      "The current amount of pastes in the database.",
 		}, func() float64 {
 			var metric float64
-			if err := DB.View(func(tx *bolt.Tx) error {
+			if err := db.Bolt.View(func(tx *bolt.Tx) error {
 				bucket := tx.Bucket([]byte("pastes"))
 				if bucket == nil {
 					return errors.New("bucket 'pastes' could not be found")