sendWithOptions method

@override Future<StreamedResponse> sendWithOptions(BaseRequest request, CacheOptions options)

Implementation

@override
Future<StreamedResponse> sendWithOptions(
  BaseRequest request,
  CacheOptions options,
) async {
  if (options.ignoreCache) {
    return await super.sendWithOptions(request, options);
  }

  final cacheId = options.keyBuilder(request);
  final store = options.store ?? _globalStore;
  var cacheResult = await store.get(cacheId);

  var shouldUpdate = options.forceUpdate ||
      cacheResult == null ||
      (!options.forceCache && cacheResult.expiry.isBefore(DateTime.now()));

  if (shouldUpdate) {
    logger?.fine(
        '[$cacheId][${request.url}] Not existing or expired cache, or forced update : starting a new request');

    try {
      if (cacheResult != null &&
          !request.headers.containsKey(HttpHeaders.ifModifiedSinceHeader)) {
        logger?.fine(
            '[$cacheId][${request.url}] Adding `${HttpHeaders.ifModifiedSinceHeader}` header');
        request.headers[HttpHeaders.ifModifiedSinceHeader] =
            HttpDate.format(cacheResult.downloadedAt);
      }

      final response = await super.sendWithOptions(request, options);

      if (cacheResult != null && response.statusCode == 304) {
        logger?.fine(
            '[$cacheId][${request.url}] Content not modified (status code 304), returning cache');
        return cacheResult;
      }

      final expiry = DateTime.now().add(options.expiry);
      cacheResult = await CachedResponse.fromResponse(response,
          expiry: expiry, id: cacheId, request: request);

      if (options.shouldBeSaved(cacheResult)) {
        logger?.fine(
            '[$cacheId][${request.url}] Saving resulting response to cache ...');
        await store.set(cacheResult);
      }

      return cacheResult;
    } catch (e) {
      if (options.returnCacheOnError && cacheResult != null) {
        return cacheResult;
      } else {
        rethrow;
      }
    }
  }

  logger?.fine(
      '[$cacheId][${request.url}] Not updating, try to use local cache ...');

  if (cacheResult == null) {
    throw NoCacheAvailableException();
  }

  logger?.fine(
      '[$cacheId][${request.url}] Result found in cache for corresponding request');

  return cacheResult;
}