first commit

db.go

@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (C) 2026 Bryan Joshua Pedini
+
+package main
+
+import (
+	"context"
+	"database/sql"
+	"log/slog"
+	"os"
+	"time"
+
+	_ "github.com/go-sql-driver/mysql"
+)
+
+// OpenDB opens the MySQL pool and pings it with a timeout, mirroring the
+// Corefile's pool limits. Must be called after the privilege drop.
+func OpenDB(logger *slog.Logger, dsn string) *sql.DB {
+	db, err := sql.Open("mysql", dsn)
+	if err != nil {
+		logger.Error("failed to open mysql pool", "error", err)
+		os.Exit(1)
+	}
+
+	db.SetMaxOpenConns(10)
+	db.SetMaxIdleConns(5)
+	db.SetConnMaxLifetime(60 * time.Second)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := db.PingContext(ctx); err != nil {
+		logger.Error("failed to reach mysql", "error", err)
+		os.Exit(1)
+	}
+
+	logger.Info("mysql pool ready")
+	return db
+}