Refactor database login into a separate module

cmd/rushlink/main.go

@@ -5,6 +5,7 @@ import (
 	"log"
 
 	"gitea.hashru.nl/dsprenkels/rushlink"
+	"gitea.hashru.nl/dsprenkels/rushlink/internal/db"
 )
 
 var (
@@ -17,14 +18,16 @@ var (
 func main() {
 	flag.Parse()
 
-	if err := rushlink.OpenDB(*databasePath); err != nil {
+	database, err := db.OpenDB(*databasePath)
+	if err != nil {
 		log.Fatalln(err)
 	}
-	defer rushlink.CloseDB()
-	if err := rushlink.OpenFileStore(*fileStorePath); err != nil {
+	defer database.Close()
+	filestore, err := db.OpenFileStore(*fileStorePath)
+	if err != nil {
 		log.Fatalln(err)
 	}
 
-	go rushlink.StartMetricsServer(*metricsListen)
-	rushlink.StartMainServer(*httpListen)
+	go rushlink.StartMetricsServer(*metricsListen, database)
+	rushlink.StartMainServer(*httpListen, database, filestore)
 }