NetworkModule.java

package br.com.mgalhardo.guidebook.dagger.module.infraestruture;

import android.app.Application;

import com.google.gson.FieldNamingPolicy;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

import javax.inject.Named;
import javax.inject.Singleton;

import br.com.mgalhardo.guidebook.dagger.module.SettingModule;
import dagger.Module;
import dagger.Provides;
import okhttp3.Cache;
import okhttp3.OkHttpClient;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.adapter.rxjava.RxJavaCallAdapterFactory;
import retrofit2.converter.gson.GsonConverterFactory;

@Module
public class NetworkModule {

    private static final int CACHE_SIZE_10_MB = 10 * 1024 * 1024;

    @Provides
    @Singleton
    Cache providesOkHttpCache(Application application) {
        int cacheSize = CACHE_SIZE_10_MB;
        return new Cache(application.getCacheDir(), cacheSize);
    }

    @Provides
    @Singleton
    Gson providesGson() {
        return new GsonBuilder()
                .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
                .setDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")
                .create();
    }

    @Provides
    @Singleton
    HttpLoggingInterceptor providesHttpLoggingInterceptor() {
        HttpLoggingInterceptor httpLoggingInterceptor = new HttpLoggingInterceptor();
        httpLoggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
        return httpLoggingInterceptor;
    }

    @Provides
    @Singleton
    OkHttpClient providesOkHttpClient(Cache cache, HttpLoggingInterceptor httpLoggingInterceptor) {
        return new OkHttpClient.Builder()
                .addInterceptor(httpLoggingInterceptor)
                .cache(cache).build();
    }

    @Provides
    @Singleton
    GsonConverterFactory providesGsonConverterFactory(Gson gson) {
        return GsonConverterFactory.create(gson);
    }

    @Provides
    @Singleton
    RxJavaCallAdapterFactory providesRxJavaCallAdapterFactory() {
        return RxJavaCallAdapterFactory.create();
    }

    @Provides
    @Singleton
    Retrofit providesRetrofit(GsonConverterFactory gsonConverterFactory, OkHttpClient okHttpClient,
                              RxJavaCallAdapterFactory rxJavaCallAdapterFactory,
                              @Named(SettingModule.BASE_URL) String baseUrl) {
        return new Retrofit.Builder().addConverterFactory(gsonConverterFactory)
                .addCallAdapterFactory(rxJavaCallAdapterFactory)
                .baseUrl(baseUrl)
                .client(okHttpClient)
                .build();
    }
}