addTrace method
add trace
Implementation
Future<void> addTrace(Dio dio) async {
// 如果内存缓存为空, 则先从本地缓存读取
if (_traceCacheValue == null) {
_traceCacheValue = await _getLocalValue(_traceCacheKey);
}
if (_traceCacheValue != null && _traceCacheValue!.isNotEmpty) {
dio.options.headers[_TRACE_HEADER] = _traceCacheValue;
}
}