Retrofit-like library with disk cache support

Question

I'm using Retrofit library from network calls. Pretty awesome. But I'm missing caching support. I can't using cache on HTTP layer (via Cache headers). Currently, I'm implementing custom caching with ObjectCache, but it's so complicated. It just should be awesome extend current Retrofit with @Cache(Expire.ONE_DAY) anotation.

My current code is like:

public static void getRestaurant(int restaurantId, String token, boolean forceNetwork, final Callback<Restaurant> listener) {
    final String key = "getRestaurant-" + restaurantId + "-" + token;
    Restaurant restaurant = (Restaurant) getCacheManager().get(key, Restaurant.class, new TypeToken<Restaurant>() {}.getType());
    if (restaurant != null && !forceNetwork) {
        Log.d(TAG, "Cache hit: " + key);
        // Cache
        listener.success(restaurant);
    } else {
        Log.d(TAG, "Network: " + key);
        // Retrofit
        getNetwork().getRestaurant(restaurantId, token, new retrofit.Callback<Response>() {
            @Override
            public void success(Response response, retrofit.client.Response response2) {
                getCacheManager().put(key, response.result.restaurant, CacheManager.ExpiryTimes.ONE_HOUR.asSeconds(), true);
                listener.success(response.result.restaurant);
            }

            @Override
            public void failure(RetrofitError error) {
                listener.failure(error.getLocalizedMessage());
            }
        });
    }
}

Now, it's just a lot of boilerplate code for each method.

Or do you know any library like Retrofit with caching support?

Thanks!

shouldn't that be automatic with the response headers? (you may need to use OkHttp with it to have disk cache, though) — njzk2, Jan 21 '15 at 20:11
see http://stackoverflow.com/questions/25887084/retrofit-okhttp-cache-https?rq=1 — njzk2, Jan 21 '15 at 20:11

score 6 · Accepted Answer · answered Nov 15 '14 at 10:58

You can wrap the underlying Client and use the request URL as a cache key.

public class CachingClient implements Client {
  private final Client delegate;

  @Override public Response execute(Request request) {
    if (!"GET".equals(request.method())) {
      return delegate.execute(request);
    }
    String url = request.url();

    // TODO look up 'url' in your cache.
    if (cacheHit) {
      return createResponse(cacheResult);
    }

    // Cache miss! Execute with the real HTTP client.
    Response response = delegate.execute(request);

    // TODO cache 'response' in your cache with the 'url' key.

    return response;
  }
}

With Retrofit v2 we are looking to enable this kind of functionality with interceptors which will not only give you a hook into the request/response chain but also allow looking up a custom annotation like @Cache.

With Retrofit 2, there is `RxCache` library! https://github.com/VictorAlbertos/RxCache — Radim Vaculik, Apr 14 '16 at 07:33

Retrofit-like library with disk cache support

1 Answers1