initial: ZeroTier-like P2P mesh VPN server with multi-tenant Web UI

internal/database/database.go

@@ -0,0 +1,84 @@
+package database
+
+import (
+	"fmt"
+	"log/slog"
+
+	"gorm.io/driver/mysql"
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+
+	"zeromesh/internal/config"
+	"zeromesh/internal/model"
+)
+
+type DB struct {
+	*gorm.DB
+}
+
+func Init(cfg *config.DatabaseConfig) (*DB, error) {
+	var db *gorm.DB
+	var err error
+
+	switch cfg.Driver {
+	case "mysql":
+		dsn := cfg.BuildDSN()
+		db, err = gorm.Open(mysql.Open(dsn), &gorm.Config{})
+	case "sqlite":
+		fallthrough
+	default:
+		db, err = gorm.Open(sqlite.Open(cfg.SQLite.Path), &gorm.Config{})
+	}
+
+	if err != nil {
+		return nil, fmt.Errorf("open database: %w", err)
+	}
+
+	sqlDB, err := db.DB()
+	if err != nil {
+		return nil, fmt.Errorf("get sql db: %w", err)
+	}
+
+	if cfg.Driver == "mysql" {
+		sqlDB.SetMaxIdleConns(cfg.MySQL.MaxIdleConns)
+		sqlDB.SetMaxOpenConns(cfg.MySQL.MaxOpenConns)
+	}
+
+	if 		cfg.AutoMigrate {
+		if err := db.AutoMigrate(
+			&model.User{},
+			&model.Network{},
+			&model.NetworkMember{},
+			&model.Node{},
+			&model.Config{},
+		&model.ApiLog{},
+		&model.ErrorLog{},
+		); err != nil {
+			return nil, fmt.Errorf("auto migrate: %w", err)
+		}
+	}
+
+	if cfg.InitData {
+		seedData(db)
+	}
+
+	slog.Info("database initialized", "driver", cfg.Driver)
+	return &DB{db}, nil
+}
+
+func seedData(db *gorm.DB) {
+	var count int64
+	db.Model(&model.Config{}).Count(&count)
+	if count > 0 {
+		return
+	}
+
+	defaults := []model.Config{
+		{Key: "allow_register", Value: "true"},
+		{Key: "default_network_pool", Value: "10.147.0.0/16"},
+	}
+	for _, c := range defaults {
+		db.Create(&c)
+	}
+	slog.Info("seed data inserted")
+}