How can I debug my retrofit API call?

Question

I'm using retrofit to get some data from the Flickr api. The method I'm making the call in looks like this:

public static List<String> getImageIds(int size) {     Call<PhotosList> call = flickrService.getPhotos(apiKey, format, "1");     Log.d("TEMP_TAG", "photo url: " + call.request().url().toString());     photoIds = new ArrayList<String>();      call.enqueue(new Callback<PhotosList>(){         @Override         public void onResponse(Call<PhotosList> call, Response<PhotosList> response) {             Log.d("TEMP_TAG", "it's getting here");             PhotosList photosList = response.body();             List<Photo> photos = photosList.getPhotos().getPhoto();              for(Photo photo : photos) {                 Log.d("TEMP_TAG", "adding photo id to list: " + photo.getId());                 photoIds.add(photo.getId());             }         }          @Override         public void onFailure(Call<PhotosList> call, Throwable t) {             // TODO: Clean up             Log.d("TEMP_TAG", "photoId: ");         }     });     Log.d("TEMP_TAG", "it's getting here too");     return photoIds; } 

However it is never getting into the onResponse() method. The first log statement within onResponse() never prints, neither does the log statement in onFailure(). When I try entering the URL that is returned by call.request().url().toString() in the browser it works fine, and I get the expected JSON. Why is my enqueue() method never firing?

Thanks for any help!

Answer 1

Use HttpLoggingInterceptor along with Retrofit.

If this helps, add this inside your build.gradle -

//Retrofit and OkHttp for Networking implementation 'com.squareup.retrofit2:retrofit:2.9.0' implementation 'com.squareup.retrofit2:converter-gson:2.9.0' //Logging Network Calls implementation 'com.squareup.okhttp3:logging-interceptor:4.9.1' 

Inside your APIClient class add this -

public class ApiClient {     private static Retrofit retrofit = null;      public static Retrofit getClient(){          HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();         interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);         OkHttpClient client = new OkHttpClient.Builder()                 .addInterceptor(interceptor)                 .build();           if(retrofit==null){             retrofit = new Retrofit.Builder()                     .baseUrl(BuildConfig.baseUrl)                     .addConverterFactory(GsonConverterFactory.create())                     .client(client)                     .build();         }         return retrofit;     } } 

Kotlin Code

val interceptor : HttpLoggingInterceptor = HttpLoggingInterceptor().apply {             level = HttpLoggingInterceptor.Level.BODY         }  val client : OkHttpClient = OkHttpClient.Builder().apply {             addInterceptor(interceptor)         }.build()   fun getService(): Service {         return Retrofit.Builder()                 .baseUrl(BASE_URL)                 .addConverterFactory(GsonConverterFactory.create())                 .addCallAdapterFactory(LiveDataCallAdapterFactory())                 .client(client)                 .build()                 .create(Service::class.java)     } 

And you will be able to log the Retrofit Network calls that you make.

Let me know if you need more information.