NetworkBoundResource: Forcing data fetch from network

I use the approach recommended in Android Architechture Guide and use NetworkBoundResource in my repository. I have SwipeRefreshLayout in my Fragments and I want to implement swipe-to-refresh action for my data in the following way:

• Force data fetch from the network regardless of the lifetime of my cache
• If fetch is successful, update cache and show data
• If fetch is unsuccessful, show previously cached data

I implements methods to get data in my repository in the following way:

public LiveData<Resource<List<Address>>> getAddresses() {
        return new NetworkBoundResource<List<Address>, AddressResponse>(appExecutors) {
            @Override
            protected void saveCallResult(@NonNull AddressResponse response) {
                database.runInTransaction(() -> {
                    addressesDao.deleteAll();
                    addressesDao.insert(response.items);
                });
            }

            @Override
            protected boolean shouldFetch(@Nullable List<Address> data) {
                // isAddressesCacheUpToDate() checks the lifetime of cached data
                return data == null || data.isEmpty() || !isAddressesCacheUpToDate(data);
            }

            @NonNull
            @Override
            protected LiveData<List<Address>> loadFromDb() {
                return addressesDao.get();
            }

            @NonNull
            @Override
            protected LiveData<ApiResponse<AddressResponse>> createCall() {
                return serviceApi.getAddresses();
            }
        }.asLiveData();
    }

I can’t realize how to modify NetworkBoundResource or my repository to implement such forced network fetches. Are there any good solutions for this task?

[santalu]

Why not just do this

  public LiveData<Resource<List<Address>>> getAddresses(boolean forceRefresh) {
    return new NetworkBoundResource<List<Address>, AddressResponse>(appExecutors) {
      @Override
      protected void saveCallResult(@NonNull AddressResponse response) {
        database.runInTransaction(() -> {
          addressesDao.deleteAll();
          addressesDao.insert(response.items);
        });
      }

      @Override
      protected boolean shouldFetch(@Nullable List<Address> data) {
        // isAddressesCacheUpToDate() checks the lifetime of cached data
        return forceRefresh || data == null || data.isEmpty() || !isAddressesCacheUpToDate(data);
      }

      @NonNull
      @Override
      protected LiveData<List<Address>> loadFromDb() {
        return addressesDao.get();
      }

      @NonNull
      @Override
      protected LiveData<ApiResponse<AddressResponse>> createCall() {
        return serviceApi.getAddresses();
      }
    }.asLiveData();
  }

[ianhanniballake]

Consider look at Store, which seeks to cover the repository pattern, encapsulating the loading logic and specifically has support for busting through your local cache.