add new method

internal/server/sv1/db_sqlite.go

@@ -82,6 +82,7 @@ func loadDBMod(llog *slog.Logger, sid string) func(*lua.LState) int {
 		L.SetField(mt, "__index", L.SetFuncs(L.NewTable(), map[string]lua.LGFunction{
 			"exec":  dbExec,
 			"query": dbQuery,
+			"query_row": dbQueryRow,
 			"close": dbClose,
 		}))
 
@@ -213,6 +214,102 @@ func dbExec(L *lua.LState) int {
 	return 2
 }
 
+func dbQueryRow(L *lua.LState) int {
+    ud := L.CheckUserData(1)
+    conn, ok := ud.Value.(*DBConnection)
+    if !ok {
+        L.Push(lua.LNil)
+        L.Push(lua.LString("invalid database connection"))
+        return 2
+    }
+
+    query := L.CheckString(2)
+
+    var args []any
+    if L.GetTop() >= 3 {
+        params := L.CheckTable(3)
+        params.ForEach(func(k lua.LValue, v lua.LValue) {
+            args = append(args, ConvertLuaTypesToGolang(v))
+        })
+    }
+
+    if conn.log {
+        conn.logger.Info("DB QueryRow",
+            slog.String("query", query),
+            slog.Any("params", args))
+    }
+
+    mtx := getDBMutex(conn.dbPath)
+    mtx.RLock()
+    defer mtx.RUnlock()
+
+    db, err := sql.Open("sqlite", conn.dbPath+"?_busy_timeout=5000&_journal_mode=WAL&_sync=NORMAL&_cache_size=-10000")
+    if err != nil {
+        L.Push(lua.LNil)
+        L.Push(lua.LString(err.Error()))
+        return 2
+    }
+    defer db.Close()
+
+    row := db.QueryRow(query, args...)
+
+	columns := []string{}
+	stmt, err := db.Prepare(query)
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("prepare failed: %v", err)))
+		return 2
+	}
+	defer stmt.Close()
+	rows, err := stmt.Query(args...)
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("query failed: %v", err)))
+		return 2
+	}
+	defer rows.Close()
+	cols, err := rows.Columns()
+	if err != nil {
+		L.Push(lua.LNil)
+		L.Push(lua.LString(fmt.Sprintf("get columns failed: %v", err)))
+		return 2
+	}
+	for _, c := range cols {
+		columns = append(columns, c)
+	}
+
+    colCount := len(columns)
+    values := make([]any, colCount)
+    valuePtrs := make([]any, colCount)
+    for i := range columns {
+        valuePtrs[i] = &values[i]
+    }
+
+    err = row.Scan(valuePtrs...)
+    if err != nil {
+        if err == sql.ErrNoRows {
+            L.Push(lua.LNil)
+            return 1
+        }
+        L.Push(lua.LNil)
+        L.Push(lua.LString(fmt.Sprintf("scan failed: %v", err)))
+        return 2
+    }
+
+    rowTable := L.NewTable()
+    for i, col := range columns {
+        val := values[i]
+        if val == nil {
+            L.SetField(rowTable, col, lua.LNil)
+        } else {
+            L.SetField(rowTable, col, ConvertGolangTypesToLua(L, val))
+        }
+    }
+
+    L.Push(rowTable)
+    return 1
+}
+
 func dbQuery(L *lua.LState) int {
 	ud := L.CheckUserData(1)
 	conn, ok := ud.Value.(*DBConnection)