style: adopt golangci-lint v2 and resolve all findings

Add .golangci.yml (v2): the standard linters plus bodyclose, errorlint, noctx, misspell, rowserrcheck, sqlclosecheck, unconvert, usestdlibvars, with gofumpt + goimports formatters. Enable the std-error-handling exclusion preset for idiomatic Close/Remove/Setenv ignores; scope-exclude SA1019 (parser.ParseDir in tools/openapigen) and ST1005 (intentional capitalized user-facing error copy that tests assert verbatim). No inline nolint directives were introduced.

Resolve all 217 findings behavior-preserving: gofumpt/goimports formatting, explicit blank assignment on intentionally ignored errors, errors.Is/errors.As and %w wrapping, context-aware stdlib calls (CommandContext/QueryContext/NewRequestWithContext/Dialer), staticcheck simplifications, removed redundant conversions, http.StatusOK and http.MethodGet, inlined the go:fix intPtr helper, and deferred sql rows Close. Add a golangci CI job mirroring the existing Go jobs.

internal/database/api_token_timestamp_test.go

@@ -3,10 +3,11 @@ package database
 import (
 	"testing"
 
-	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
 	"gorm.io/driver/sqlite"
 	"gorm.io/gorm"
 	"gorm.io/gorm/logger"
+
+	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
 )
 
 func TestNormalizeApiTokenCreatedAtSeconds(t *testing.T) {

internal/database/db.go

@@ -4,6 +4,7 @@ package database
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -43,7 +44,7 @@ func IsPostgres() bool {
 	if db == nil {
 		return config.GetDBKind() == "postgres"
 	}
-	return db.Dialector.Name() == "postgres"
+	return db.Name() == "postgres"
 }
 
 // Dialect returns the active GORM dialect name, or "" if the DB is not open.
@@ -51,7 +52,7 @@ func Dialect() string {
 	if db == nil {
 		return ""
 	}
-	return db.Dialector.Name()
+	return db.Name()
 }
 
 const (
@@ -363,7 +364,6 @@ func initUser() error {
 	}
 	if empty {
 		hashedPassword, err := crypto.HashPasswordAsBcrypt(defaultPassword)
-
 		if err != nil {
 			log.Printf("Error hashing default password: %v", err)
 			return err
@@ -580,7 +580,7 @@ func fail2banCanEnforce() bool {
 	if runtime.GOOS == "windows" {
 		return false
 	}
-	return exec.Command("fail2ban-client", "-h").Run() == nil
+	return exec.CommandContext(context.Background(), "fail2ban-client", "-h").Run() == nil
 }
 
 // clearLegacyProxySettings drops the deprecated panelProxy/tgBotProxy rows so a
@@ -1038,7 +1038,7 @@ func InitDB(dbPath string) error {
 		}
 	default:
 		dir := path.Dir(dbPath)
-		if err = os.MkdirAll(dir, 0755); err != nil {
+		if err = os.MkdirAll(dir, 0o755); err != nil {
 			return err
 		}
 		// Keep journal_mode=DELETE so the DB stays a single file (no -wal/-shm
@@ -1065,7 +1065,7 @@ func InitDB(dbPath string) error {
 			"PRAGMA temp_store=MEMORY",
 		}
 		for _, p := range pragmas {
-			if _, err := sqlDB.Exec(p); err != nil {
+			if _, err := sqlDB.ExecContext(context.Background(), p); err != nil {
 				return err
 			}
 		}

internal/database/dump_sqlite.go

@@ -1,6 +1,7 @@
 package database
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
 	"os"
@@ -50,23 +51,21 @@ func DumpSQLiteToBytes(srcPath string) ([]byte, error) {
 	// Tables in creation order, each followed by its data.
 	type object struct{ name, ddl string }
 	var tables []object
-	rows, err := sqlDB.Query(`SELECT name, sql FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%' AND sql IS NOT NULL ORDER BY rowid`)
+	rows, err := sqlDB.QueryContext(context.Background(), `SELECT name, sql FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%' AND sql IS NOT NULL ORDER BY rowid`)
 	if err != nil {
 		return nil, err
 	}
+	defer rows.Close()
 	for rows.Next() {
 		var o object
 		if err := rows.Scan(&o.name, &o.ddl); err != nil {
-			rows.Close()
 			return nil, err
 		}
 		tables = append(tables, o)
 	}
 	if err := rows.Err(); err != nil {
-		rows.Close()
 		return nil, err
 	}
-	rows.Close()
 
 	for _, t := range tables {
 		b.WriteString(t.ddl)
@@ -85,24 +84,22 @@ func DumpSQLiteToBytes(srcPath string) ([]byte, error) {
 	}
 
 	// Indexes, triggers and views after the data is in place.
-	rows2, err := sqlDB.Query(`SELECT sql FROM sqlite_master WHERE type IN ('index','trigger','view') AND sql IS NOT NULL ORDER BY rowid`)
+	rows2, err := sqlDB.QueryContext(context.Background(), `SELECT sql FROM sqlite_master WHERE type IN ('index','trigger','view') AND sql IS NOT NULL ORDER BY rowid`)
 	if err != nil {
 		return nil, err
 	}
+	defer rows2.Close()
 	for rows2.Next() {
 		var ddl string
 		if err := rows2.Scan(&ddl); err != nil {
-			rows2.Close()
 			return nil, err
 		}
 		b.WriteString(ddl)
 		b.WriteString(";\n")
 	}
 	if err := rows2.Err(); err != nil {
-		rows2.Close()
 		return nil, err
 	}
-	rows2.Close()
 
 	b.WriteString("COMMIT;\n")
 
@@ -131,7 +128,7 @@ func RestoreSQLite(dumpPath, dstPath string) error {
 	}
 
 	// mattn/go-sqlite3 executes every statement in a multi-statement string.
-	if _, err := sqlDB.Exec(string(script)); err != nil {
+	if _, err := sqlDB.ExecContext(context.Background(), string(script)); err != nil {
 		sqlDB.Close()
 		os.Remove(dstPath)
 		return fmt.Errorf("restore failed: %w", err)
@@ -141,7 +138,7 @@ func RestoreSQLite(dumpPath, dstPath string) error {
 
 // dumpTableData appends one INSERT statement per row of table to b.
 func dumpTableData(db *sql.DB, table string, b *strings.Builder) error {
-	rows, err := db.Query(`SELECT * FROM "` + table + `"`)
+	rows, err := db.QueryContext(context.Background(), `SELECT * FROM "`+table+`"`)
 	if err != nil {
 		return err
 	}
@@ -213,6 +210,6 @@ func quoteSQLiteText(s string) string {
 
 func sqliteTableExists(db *sql.DB, name string) bool {
 	var found string
-	err := db.QueryRow(`SELECT name FROM sqlite_master WHERE type='table' AND name=?`, name).Scan(&found)
+	err := db.QueryRowContext(context.Background(), `SELECT name FROM sqlite_master WHERE type='table' AND name=?`, name).Scan(&found)
 	return err == nil
 }

internal/database/migrate_data.go

@@ -67,7 +67,7 @@ func MigrateData(srcPath, dstDSN string) error {
 		return errors.New("destination DSN is required")
 	}
 
-	if err := os.MkdirAll(path.Dir(srcPath), 0755); err != nil {
+	if err := os.MkdirAll(path.Dir(srcPath), 0o755); err != nil {
 		return err
 	}
 
@@ -144,7 +144,7 @@ func ExportPostgresToSQLite(srcDSN, dstPath string) error {
 	if srcDSN == "" {
 		return errors.New("source DSN is required")
 	}
-	if err := os.MkdirAll(path.Dir(dstPath), 0755); err != nil {
+	if err := os.MkdirAll(path.Dir(dstPath), 0o755); err != nil {
 		return err
 	}
 	// Start from an empty file so AutoMigrate creates the canonical schema.