#3222 Merge master into Structured Data branch, fix conflicts - review fixes

app/src/main/java/fr/free/nrw/commons/MediaDataExtractor.java

@@ -1,20 +1,18 @@
 package fr.free.nrw.commons;
 
+import static fr.free.nrw.commons.depictions.Media.DepictedImagesFragment.PAGE_ID_PREFIX;
+
 import androidx.core.text.HtmlCompat;
-
-
 import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
-
+import fr.free.nrw.commons.media.MediaClient;
+import io.reactivex.Single;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Map;
-
 import javax.inject.Inject;
 import javax.inject.Singleton;
-
+import org.jetbrains.annotations.NotNull;
-import fr.free.nrw.commons.media.MediaClient;
-import io.reactivex.Single;
 import timber.log.Timber;
 
 /**
@@ -25,10 +23,15 @@ import timber.log.Timber;
  */
 @Singleton
 public class MediaDataExtractor {
-    private final MediaClient mediaClient;
+
+  private static final int LABEL_BEGIN_INDEX = 3;
+  private static final int LABEL_END_OFFSET = 3;
+  private static final int ID_BEGIN_INDEX = 1;
+  private static final int ID_END_OFFSET = 1;
+  private final MediaClient mediaClient;
 
     @Inject
-    public MediaDataExtractor(MediaClient mediaClient) {
+    public MediaDataExtractor(final MediaClient mediaClient) {
         this.mediaClient = mediaClient;
     }
 
@@ -38,31 +41,35 @@ public class MediaDataExtractor {
      * @param filename for which the details are to be fetched
      * @return full Media object with all details including deletion status and talk page
      */
-    public Single<Media> fetchMediaDetails(String filename, String pageId) {
+    public Single<Media> fetchMediaDetails(final String filename, final String pageId) {
-        Single<Media> mediaSingle = getMediaFromFileName(filename);
+      return Single.zip(getMediaFromFileName(filename),
-        Single<Boolean> pageExistsSingle = mediaClient.checkPageExistsUsingTitle("Commons:Deletion_requests/" + filename);
+            mediaClient.checkPageExistsUsingTitle("Commons:Deletion_requests/" + filename),
-        Single<String> discussionSingle = getDiscussion(filename);
+            getDiscussion(filename),
-        Single<String> captionSingle = getCaption("M"+pageId);
+            getCaption(PAGE_ID_PREFIX + pageId),
-        Single<JsonObject> depictionSingle = getDepictions(filename);
+            getDepictions(filename),
-        return Single.zip(mediaSingle, pageExistsSingle, discussionSingle, captionSingle, depictionSingle, (media, deletionStatus, discussion, caption, depiction) -> {
+            this::combineToMedia);
-            media.setDiscussion(discussion);
-            media.setCaption(caption);
-            media.setDepiction(formatDepictions(depiction));
-            if (deletionStatus) {
-                media.setRequestedDeletion();
-            }
-            return media;
-        });
     }
 
-    /**
+  @NotNull
+  private Media combineToMedia(final Media media, final Boolean deletionStatus, final String discussion,
+      final String caption, final JsonObject depiction) {
+    media.setDiscussion(discussion);
+    media.setCaption(caption);
+    media.setDepiction(formatDepictions(depiction));
+    if (deletionStatus) {
+        media.setRequestedDeletion();
+    }
+    return media;
+  }
+
+  /**
      * Obtains captions using filename
      * @param wikibaseIdentifier
      *
      * @return caption for the image in user's locale
      * Ex: "a nice painting" (english locale) and "No Caption" in case the caption is not available for the image
      */
-    private Single<String> getCaption(String wikibaseIdentifier) {
+    private Single<String> getCaption(final String wikibaseIdentifier) {
         return mediaClient.getCaptionByWikibaseIdentifier(wikibaseIdentifier);
     }
 
@@ -72,27 +79,23 @@ public class MediaDataExtractor {
      * @return List containing map for depictions, the map has two keys,
      *  first key is for the label and second is for the url of the item
      */
-    private ArrayList<Map<String, String>> formatDepictions(JsonObject mediaResponse) {
+    private ArrayList<Map<String, String>> formatDepictions(final JsonObject mediaResponse) {
         try {
-            JsonArray depictionArray = (JsonArray) mediaResponse.get("Depiction");
+            final JsonArray depictionArray = (JsonArray) mediaResponse.get("Depiction");
-            ArrayList<Map<String, String>> depictedItemList = new ArrayList<>();
+            final ArrayList<Map<String, String>> depictedItemList = new ArrayList<>();
-            try {
+            for (int i = 0; i <depictionArray.size() ; i++) {
-                for (int i = 0; i <depictionArray.size() ; i++) {
+                final JsonObject depictedItem = (JsonObject) depictionArray.get(i);
-                    JsonObject depictedItem = (JsonObject) depictionArray.get(i);
+                final Map <String, String> depictedObject = new HashMap<>();
-                    Map <String, String> depictedObject = new HashMap<>();
+                final String label = depictedItem.get("label").toString();
-                    String label = depictedItem.get("label").toString();
+                final String id =  depictedItem.get("id").toString();
-                    String id =  depictedItem.get("id").toString();
+                final String transformedLabel = label.substring(LABEL_BEGIN_INDEX, label.length()- LABEL_END_OFFSET);
-                    String transformedLabel = label.substring(3, label.length()-3);
+                final String transformedId = id.substring(ID_BEGIN_INDEX,id.length() - ID_END_OFFSET);
-                    String transformedId = id.substring(1,id.length() - 1);
+                depictedObject.put("label", transformedLabel); //remove the additional characters obtained in label and ID object to extract the relevant string (since the string also contains extra quites that are not required)
-                    depictedObject.put("label", transformedLabel); //remove the additional characters obtained in label and ID object to extract the relevant string (since the string also contains extra quites that are not required)
+                depictedObject.put("id", transformedId);
-                    depictedObject.put("id", transformedId);
+                depictedItemList.add(depictedObject);
-                    depictedItemList.add(depictedObject);
-                }
-                return depictedItemList;
-            } catch (NullPointerException e) {
-                return new ArrayList<>();
             }
-        } catch (ClassCastException c) {
+            return depictedItemList;
+        } catch (final ClassCastException | NullPointerException ignore) {
             return new ArrayList<>();
         }
     }
@@ -102,13 +105,9 @@ public class MediaDataExtractor {
      * @param filename the filename we will return the caption for
      * @return a map containing caption and depictions (empty string in the map if no caption/depictions)
      */
- private Single<JsonObject> getDepictions(String filename)  {
+ private Single<JsonObject> getDepictions(final String filename)  {
          return mediaClient.getCaptionAndDepictions(filename)
-                .map(mediaResponse -> {
+             .doOnError(throwable -> Timber.e(throwable, "error while fetching depictions"));
-                    return mediaResponse;
-                }).doOnError(throwable -> {
-                    Timber.e(throwable+ "error while fetching depictions");
-                 });
     }
 
     /**
@@ -116,7 +115,7 @@ public class MediaDataExtractor {
      * @param filename Eg. File:Test.jpg
      * @return return data rich Media object
      */
-    public Single<Media> getMediaFromFileName(String filename) {
+    public Single<Media> getMediaFromFileName(final String filename) {
         return mediaClient.getMedia(filename);
     }
 
@@ -125,7 +124,7 @@ public class MediaDataExtractor {
      * @param filename
      * @return
      */
-    private Single<String> getDiscussion(String filename) {
+    private Single<String> getDiscussion(final String filename) {
         return mediaClient.getPageHtml(filename.replace("File", "File talk"))
                 .map(discussion -> HtmlCompat.fromHtml(discussion, HtmlCompat.FROM_HTML_MODE_LEGACY).toString())
                 .onErrorReturn(throwable -> {

app/src/main/java/fr/free/nrw/commons/category/CategoryImagesListFragment.java

@@ -1,5 +1,9 @@
 package fr.free.nrw.commons.category;
 
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+import static fr.free.nrw.commons.depictions.Media.DepictedImagesFragment.PAGE_ID_PREFIX;
+
 import android.annotation.SuppressLint;
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -12,15 +16,7 @@ import android.widget.ListAdapter;
 import android.widget.ProgressBar;
 import android.widget.RelativeLayout;
 import android.widget.TextView;
-
 import androidx.annotation.Nullable;
-
-import java.util.List;
-import java.util.concurrent.TimeUnit;
-
-import javax.inject.Inject;
-import javax.inject.Named;
-
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import dagger.android.support.DaggerFragment;
@@ -33,11 +29,12 @@ import fr.free.nrw.commons.utils.ViewUtil;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.schedulers.Schedulers;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import javax.inject.Inject;
+import javax.inject.Named;
 import timber.log.Timber;
 
-import static android.view.View.GONE;
-import static android.view.View.VISIBLE;
-
 /**
  * Displays images for a particular category with load more on scrolling incorporated
  */
@@ -261,7 +258,7 @@ public class CategoryImagesListFragment extends DaggerFragment {
         isLoading = false;
         statusTextView.setVisibility(GONE);
         for (Media m : collection) {
-            replaceTitlesWithCaptions("M"+m.getPageId(), mediaSize++);
+            replaceTitlesWithCaptions(PAGE_ID_PREFIX + m.getPageId(), mediaSize++);
         }
     }
 

app/src/main/java/fr/free/nrw/commons/contributions/ContributionViewHolder.java

@@ -1,5 +1,7 @@
 package fr.free.nrw.commons.contributions;
 
+import static fr.free.nrw.commons.depictions.Media.DepictedImagesFragment.PAGE_ID_PREFIX;
+
 import android.graphics.Color;
 import android.graphics.drawable.ColorDrawable;
 import android.net.Uri;
@@ -117,7 +119,7 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
             titleView.setText(contribution.getDisplayTitle());
         } else {
             Timber.d("Fetching caption for %s", contribution.getFilename());
-            String wikibaseMediaId = "M"+contribution.getPageId(); // Create Wikibase media id from the page id. Example media id: M80618155 for https://commons.wikimedia.org/wiki/File:Tantanmen.jpeg with has the pageid 80618155
+            String wikibaseMediaId = PAGE_ID_PREFIX + contribution.getPageId(); // Create Wikibase media id from the page id. Example media id: M80618155 for https://commons.wikimedia.org/wiki/File:Tantanmen.jpeg with has the pageid 80618155
             compositeDisposable.add(mediaClient.getCaptionByWikibaseIdentifier(wikibaseMediaId)
                     .subscribeOn(Schedulers.io())
                     .observeOn(AndroidSchedulers.mainThread())

app/src/main/java/fr/free/nrw/commons/db/Converters.java

@@ -12,6 +12,9 @@ import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
 
+/**
+ * This class supplies converters to write/read types to/from the database.
+ */
 public class Converters {
 
     public static Gson getGson() {

app/src/main/java/fr/free/nrw/commons/depictions/GridViewAdapter.java

@@ -57,7 +57,7 @@ public class GridViewAdapter extends ArrayAdapter {
                 data = new ArrayList<>();
                 return false;
             }
-            if (data.size() <= 0) {
+            if (data.size() == 0) {
                 return false;
             }
             String fileName = data.get(0).getFilename();

app/src/main/java/fr/free/nrw/commons/depictions/Media/DepictedImagesContract.java

@@ -34,7 +34,7 @@ public interface DepictedImagesContract {
         /**
          * Seat caption to the image at the given position
          */
-        void handleLabelforImage(String s, int position);
+        void handleLabelforImage(String caption, int position);
 
         /**
          * Display snackbar

app/src/main/java/fr/free/nrw/commons/depictions/Media/DepictedImagesFragment.java

@@ -1,5 +1,8 @@
 package fr.free.nrw.commons.depictions.Media;
 
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -11,26 +14,20 @@ import android.widget.ListAdapter;
 import android.widget.ProgressBar;
 import android.widget.RelativeLayout;
 import android.widget.TextView;
-
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
-
-import java.util.List;
-
-import javax.inject.Inject;
-
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import dagger.android.support.DaggerFragment;
 import fr.free.nrw.commons.Media;
 import fr.free.nrw.commons.R;
-import fr.free.nrw.commons.depictions.WikidataItemDetailsActivity;
 import fr.free.nrw.commons.depictions.GridViewAdapter;
+import fr.free.nrw.commons.depictions.WikidataItemDetailsActivity;
 import fr.free.nrw.commons.utils.NetworkUtils;
 import fr.free.nrw.commons.utils.ViewUtil;
-
+import java.util.List;
-import static android.view.View.GONE;
+import javax.inject.Inject;
-import static android.view.View.VISIBLE;
+import timber.log.Timber;
 
 /**
  * Fragment for showing image list after selected an item from SearchActivity In Explore
@@ -38,6 +35,7 @@ import static android.view.View.VISIBLE;
 public class DepictedImagesFragment extends DaggerFragment implements DepictedImagesContract.View {
 
 
+    public static final String PAGE_ID_PREFIX = "M";
     @BindView(R.id.statusMessage)
     TextView statusTextView;
     @BindView(R.id.loadingImagesProgressBar)
@@ -87,7 +85,9 @@ public class DepictedImagesFragment extends DaggerFragment implements DepictedIm
         presenter.initList(entityId);
         if (!NetworkUtils.isInternetConnectionEstablished(getContext())) {
             handleNoInternet();
-        } else presenter.initList(entityId);
+        } else {
+            presenter.initList(entityId);
+        }
     }
 
     /**
@@ -150,9 +150,9 @@ public class DepictedImagesFragment extends DaggerFragment implements DepictedIm
      * Seat caption to the image at the given position
      */
     @Override
-    public void handleLabelforImage(String s, int position) {
+    public void handleLabelforImage(String caption, int position) {
-        if (!s.trim().equals(getString(R.string.detail_caption_empty))) {
+        if (!caption.trim().equals(getString(R.string.detail_caption_empty))) {
-            gridAdapter.getItem(position).setThumbnailTitle(s);
+            gridAdapter.getItem(position).setThumbnailTitle(caption);
             gridAdapter.notifyDataSetChanged();
         }
     }
@@ -250,15 +250,15 @@ public class DepictedImagesFragment extends DaggerFragment implements DepictedIm
 
             try {
                 ((WikidataItemDetailsActivity) getContext()).viewPagerNotifyDataSetChanged();
-            } catch (Exception e) {
+            } catch (RuntimeException e) {
-                e.printStackTrace();
+                Timber.e(e);
             }
         }
         progressBar.setVisibility(GONE);
         isLoading = false;
         statusTextView.setVisibility(GONE);
-        for (Media m : collection) {
+        for (Media media : collection) {
-            presenter.replaceTitlesWithCaptions("M"+m.getPageId(), mediaSize++);
+            presenter.replaceTitlesWithCaptions(PAGE_ID_PREFIX +media.getPageId(), mediaSize++);
         }
     }
 }

app/src/main/java/fr/free/nrw/commons/depictions/Media/DepictedImagesPresenter.java

@@ -1,26 +1,22 @@
 package fr.free.nrw.commons.depictions.Media;
 
+import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
+import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
+
 import android.annotation.SuppressLint;
-
-import java.lang.reflect.Proxy;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.TimeUnit;
-
-import javax.inject.Inject;
-import javax.inject.Named;
-
 import fr.free.nrw.commons.Media;
 import fr.free.nrw.commons.explore.depictions.DepictsClient;
 import fr.free.nrw.commons.kvstore.JsonKvStore;
 import fr.free.nrw.commons.media.MediaClient;
 import io.reactivex.Scheduler;
 import io.reactivex.disposables.CompositeDisposable;
+import java.lang.reflect.Proxy;
+import java.util.ArrayList;
+import java.util.List;
+import javax.inject.Inject;
+import javax.inject.Named;
 import timber.log.Timber;
 
-import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
-import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
-
 /**
  * Presenter for DepictedImagesFragment
  */
@@ -31,7 +27,6 @@ public class DepictedImagesPresenter implements DepictedImagesContract.UserActio
                     DepictedImagesContract.View.class.getClassLoader(),
                     new Class[]{DepictedImagesContract.View.class},
                     (proxy, method, methodArgs) -> null);
-    private static int TIMEOUT_SECONDS = 15;
     DepictsClient depictsClient;
     MediaClient mediaClient;
     @Named("default_preferences")
@@ -76,10 +71,9 @@ public class DepictedImagesPresenter implements DepictedImagesContract.UserActio
         view.setLoadingStatus(true);
         view.progressBarVisible(true);
         view.setIsLastPage(false);
-        compositeDisposable.add(depictsClient.fetchImagesForDepictedItem(entityId, 25, 0)
+        compositeDisposable.add(depictsClient.fetchImagesForDepictedItem(entityId, 0)
                 .subscribeOn(ioScheduler)
                 .observeOn(mainThreadScheduler)
-                .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
                 .subscribe(this::handleSuccess, this::handleError));
     }
 
@@ -90,10 +84,9 @@ public class DepictedImagesPresenter implements DepictedImagesContract.UserActio
     @Override
     public void fetchMoreImages() {
         view.progressBarVisible(true);
-        compositeDisposable.add(depictsClient.fetchImagesForDepictedItem(entityId, 25, queryList.size())
+        compositeDisposable.add(depictsClient.fetchImagesForDepictedItem(entityId, queryList.size())
                 .subscribeOn(ioScheduler)
                 .observeOn(mainThreadScheduler)
-                .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
                 .subscribe(this::handlePaginationSuccess, this::handleError));
     }
 
@@ -150,9 +143,8 @@ public class DepictedImagesPresenter implements DepictedImagesContract.UserActio
         compositeDisposable.add(mediaClient.getCaptionByWikibaseIdentifier(wikibaseIdentifier)
                 .subscribeOn(ioScheduler)
                 .observeOn(mainThreadScheduler)
-                .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
+                .subscribe(caption -> {
-                .subscribe(subscriber -> {
+                    view.handleLabelforImage(caption, position);
-                    view.handleLabelforImage(subscriber, position);
                 }));
 
     }

app/src/main/java/fr/free/nrw/commons/depictions/SubClass/SubDepictionListPresenter.java

@@ -1,14 +1,7 @@
 package fr.free.nrw.commons.depictions.SubClass;
 
-import java.io.IOException;
+import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
-import java.lang.reflect.Proxy;
+import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.List;
-import java.util.concurrent.TimeUnit;
-
-import javax.inject.Inject;
-import javax.inject.Named;
 
 import fr.free.nrw.commons.explore.depictions.DepictsClient;
 import fr.free.nrw.commons.explore.recentsearches.RecentSearch;
@@ -16,14 +9,17 @@ import fr.free.nrw.commons.explore.recentsearches.RecentSearchesDao;
 import fr.free.nrw.commons.mwapi.OkHttpJsonApiClient;
 import fr.free.nrw.commons.upload.structure.depictions.DepictedItem;
 import io.reactivex.Scheduler;
-import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.CompositeDisposable;
-import io.reactivex.schedulers.Schedulers;
+import java.io.IOException;
+import java.lang.reflect.Proxy;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import javax.inject.Inject;
+import javax.inject.Named;
 import timber.log.Timber;
 
-import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
-import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
-
 /**
 * Presenter for parent classes and child classes of Depicted items in Explore
  */
@@ -155,13 +151,8 @@ public class SubDepictionListPresenter implements SubDepictionListContract.UserA
      */
     private void handleError(Throwable throwable) {
         Timber.e(throwable, "Error occurred while loading queried depictions");
-        try {
+        view.initErrorView();
-            view.initErrorView();
+        view.showSnackbar();
-            view.showSnackbar();
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
-
     }
 
 }

app/src/main/java/fr/free/nrw/commons/depictions/WikidataItemDetailsActivity.java

@@ -33,7 +33,7 @@ import fr.free.nrw.commons.upload.structure.depictions.DepictedItem;
 public class WikidataItemDetailsActivity extends NavigationBaseActivity implements MediaDetailPagerFragment.MediaDetailProvider, AdapterView.OnItemClickListener {
     private FragmentManager supportFragmentManager;
     private DepictedImagesFragment depictionImagesListFragment;
-    private MediaDetailPagerFragment mediaDetails;
+    private MediaDetailPagerFragment mediaDetailPagerFragment;
     /**
      * Name of the depicted item
      * Ex: Rabbit
@@ -78,8 +78,8 @@ public class WikidataItemDetailsActivity extends NavigationBaseActivity implemen
      * The viewpager will notified that number of items have changed.
      */
     public void viewPagerNotifyDataSetChanged() {
-        if (mediaDetails!=null){
+        if (mediaDetailPagerFragment !=null){
-            mediaDetails.notifyDataSetChanged();
+            mediaDetailPagerFragment.notifyDataSetChanged();
         }
     }
 
@@ -129,18 +129,18 @@ public class WikidataItemDetailsActivity extends NavigationBaseActivity implemen
         tabLayout.setVisibility(View.GONE);
         viewPager.setVisibility(View.GONE);
         mediaContainer.setVisibility(View.VISIBLE);
-        if (mediaDetails == null || !mediaDetails.isVisible()) {
+        if (mediaDetailPagerFragment == null || !mediaDetailPagerFragment.isVisible()) {
             // set isFeaturedImage true for featured images, to include author field on media detail
-            mediaDetails = new MediaDetailPagerFragment(false, true);
+            mediaDetailPagerFragment = new MediaDetailPagerFragment(false, true);
             FragmentManager supportFragmentManager = getSupportFragmentManager();
             supportFragmentManager
                     .beginTransaction()
-                    .replace(R.id.mediaContainer, mediaDetails)
+                    .replace(R.id.mediaContainer, mediaDetailPagerFragment)
                     .addToBackStack(null)
                     .commit();
             supportFragmentManager.executePendingTransactions();
         }
-        mediaDetails.showImage(position);
+        mediaDetailPagerFragment.showImage(position);
         forceInitBackButton();
     }
 

app/src/main/java/fr/free/nrw/commons/di/NetworkingModule.java

@@ -54,7 +54,6 @@ public class NetworkingModule {
 
     public static final String NAMED_COMMONS_WIKI_SITE = "commons-wikisite";
     private static final String NAMED_WIKI_DATA_WIKI_SITE = "wikidata-wikisite";
-    private static final String NAMED_COMMONS_WIKI = "commonswiki";
 
     public static final String NAMED_COMMONS_CSRF = "commons-csrf";
 
@@ -138,12 +137,6 @@ public class NetworkingModule {
         return new WikiSite(BuildConfig.WIKIDATA_URL);
     }
 
-    @Provides
-    @Singleton
-    @Named(NAMED_COMMONS_WIKI)
-    public WikiSite provideCommonsWiki() {
-        return new WikiSite(BuildConfig.COMMONS_URL);
-    }
 
     /**
      * Gson objects are very heavy. The app should ideally be using just one instance of it instead of creating new instances everywhere.
@@ -230,7 +223,7 @@ public class NetworkingModule {
 
     @Provides
     @Singleton
-    public MediaDetailInterface providesMediaDetailInterface(@Named(NAMED_COMMONS_WIKI) WikiSite commonsWikisite) {
+    public MediaDetailInterface providesMediaDetailInterface(@Named(NAMED_COMMONS_WIKI_SITE) WikiSite commonsWikisite) {
         return ServiceFactory.get(commonsWikisite, BuildConfig.COMMONS_URL, MediaDetailInterface.class);
     }
 

app/src/main/java/fr/free/nrw/commons/explore/depictions/DepictsClient.java

@@ -105,7 +105,7 @@ public class DepictsClient {
     /**
      * @return list of images for a particular depict entity
      */
-    public Observable<List<Media>> fetchImagesForDepictedItem(String query, int limit, int sroffset) {
+    public Observable<List<Media>> fetchImagesForDepictedItem(String query, int sroffset) {
         return mediaInterface.fetchImagesForDepictedItem("haswbstatement:" + BuildConfig.DEPICTS_PROPERTY + "=" + query, String.valueOf(sroffset))
                 .map(mwQueryResponse -> {
                     List<Media> mediaList =  new ArrayList<>();

app/src/main/java/fr/free/nrw/commons/explore/depictions/SearchDepictionsFragmentPresenter.java

@@ -1,27 +1,24 @@
 package fr.free.nrw.commons.explore.depictions;
 
-import java.lang.reflect.Proxy;
+import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
-import java.util.ArrayList;
+import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
-import java.util.Date;
-import java.util.List;
-import java.util.concurrent.TimeUnit;
-
-import javax.inject.Inject;
-import javax.inject.Named;
 
 import fr.free.nrw.commons.di.CommonsDaggerSupportFragment;
 import fr.free.nrw.commons.explore.recentsearches.RecentSearch;
 import fr.free.nrw.commons.explore.recentsearches.RecentSearchesDao;
 import fr.free.nrw.commons.kvstore.JsonKvStore;
 import fr.free.nrw.commons.upload.structure.depictions.DepictedItem;
-
 import io.reactivex.Scheduler;
 import io.reactivex.disposables.CompositeDisposable;
+import java.lang.reflect.Proxy;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import javax.inject.Inject;
+import javax.inject.Named;
 import timber.log.Timber;
 
-import static fr.free.nrw.commons.di.CommonsApplicationModule.IO_THREAD;
-import static fr.free.nrw.commons.di.CommonsApplicationModule.MAIN_THREAD;
-
 /**
  * The presenter class for SearchDepictionsFragment
  */
@@ -105,13 +102,8 @@ public class SearchDepictionsFragmentPresenter extends CommonsDaggerSupportFragm
      */
     private void handleError(Throwable throwable) {
         Timber.e(throwable, "Error occurred while loading queried depictions");
-        try {
+        view.initErrorView();
-            view.initErrorView();
+        view.showSnackbar();
-            view.showSnackbar();
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
-
     }
 
     /**

app/src/main/java/fr/free/nrw/commons/explore/images/SearchImageFragment.java

@@ -41,6 +41,7 @@ import timber.log.Timber;
 
 import static android.view.View.GONE;
 import static android.view.View.VISIBLE;
+import static fr.free.nrw.commons.depictions.Media.DepictedImagesFragment.PAGE_ID_PREFIX;
 
 /**
  * Displays the image search screen.
@@ -205,7 +206,7 @@ public class SearchImageFragment extends CommonsDaggerSupportFragment {
             imagesAdapter.notifyDataSetChanged();
             ((SearchActivity)getContext()).viewPagerNotifyDataSetChanged();
             for (Media m : mediaList) {
-                replaceTitlesWithCaptions("M"+m.getPageId(), mediaSize++);
+                replaceTitlesWithCaptions(PAGE_ID_PREFIX + m.getPageId(), mediaSize++);
             }
         }
     }
@@ -215,13 +216,13 @@ public class SearchImageFragment extends CommonsDaggerSupportFragment {
      * When captions are retrieved they replace title
      */
 
-        public void replaceTitlesWithCaptions(String wikibaseIdentifier, int i) {
+        public void replaceTitlesWithCaptions(String wikibaseIdentifier, int position) {
             compositeDisposable.add(mediaClient.getCaptionByWikibaseIdentifier(wikibaseIdentifier)
                     .subscribeOn(Schedulers.io())
                     .observeOn(AndroidSchedulers.mainThread())
                     .timeout(TIMEOUT_SECONDS, TimeUnit.SECONDS)
                     .subscribe(subscriber -> {
-                        handleLabelforImage(subscriber, i);
+                        handleLabelforImage(subscriber, position);
                     }));
 
         }

app/src/main/java/fr/free/nrw/commons/media/MediaClient.java

@@ -2,36 +2,28 @@ package fr.free.nrw.commons.media;
 
 
 import android.annotation.SuppressLint;
-
 import androidx.annotation.NonNull;
-
-import org.wikipedia.dataclient.mwapi.MwQueryResponse;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Locale;
-import java.util.Map;
-
-import javax.inject.Inject;
-import javax.inject.Singleton;
-
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
 import com.google.gson.internal.LinkedTreeMap;
-
-import java.util.Date;
-
-
 import fr.free.nrw.commons.BuildConfig;
 import fr.free.nrw.commons.Media;
 import fr.free.nrw.commons.utils.CommonsDateUtil;
 import io.reactivex.Observable;
 import io.reactivex.Single;
 import io.reactivex.schedulers.Schedulers;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+import org.wikipedia.dataclient.mwapi.MwQueryResponse;
 import timber.log.Timber;
 
 /**
@@ -186,26 +178,23 @@ public class MediaClient {
     public Single<String> getCaptionByWikibaseIdentifier(String wikibaseIdentifier) {
         return mediaDetailInterface.getCaptionForImage(Locale.getDefault().getLanguage(), wikibaseIdentifier)
                 .map(mediaDetailResponse -> {
-                    if (mediaDetailResponse != null && mediaDetailResponse.getSuccess() != null && mediaDetailResponse.getSuccess() == 1 && mediaDetailResponse.getEntities() != null) {
+                    if (isSuccess(mediaDetailResponse)) {
-                        Map<String, CommonsWikibaseItem> entities = mediaDetailResponse.getEntities();
+                        for (CommonsWikibaseItem wikibaseItem : mediaDetailResponse.getEntities().values()) {
-                        try {
+                            for (Caption caption : wikibaseItem.getLabels().values()) {
-                            Map.Entry<String, CommonsWikibaseItem> entry = entities.entrySet().iterator().next();
-                            CommonsWikibaseItem commonsWikibaseItem = entry.getValue();
-                                Map<String, Caption> labels = commonsWikibaseItem.getLabels();
-                                Map.Entry<String, Caption> captionEntry = labels.entrySet().iterator().next();
-                                Caption caption = captionEntry.getValue();
                                 return caption.getValue();
-
+                            }
-                        } catch (Exception e) {
-                            return NO_CAPTION;
                         }
                     }
-                        return NO_CAPTION;
+                    return NO_CAPTION;
-
                 })
                 .singleOrError();
     }
 
+    private boolean isSuccess(MediaDetailResponse response) {
+        return response != null && response.getSuccess() != null
+            && response.getSuccess() == 1 && response.getEntities() != null;
+    }
+
     /**
      * Fetches Structured data from API
      *
@@ -214,9 +203,7 @@ public class MediaClient {
      */
     public Single<JsonObject> getCaptionAndDepictions(String filename)  {
         return mediaDetailInterface.fetchStructuredDataByFilename(Locale.getDefault().getLanguage(), filename)
-                .map(mediaDetailResponse -> {
+                .map(this::fetchCaptionandDepictionsFromMediaDetailResponse)
-                        return fetchCaptionandDepictionsFromMediaDetailResponse(mediaDetailResponse);
-                })
                 .singleOrError();
     }
 
@@ -228,7 +215,7 @@ public class MediaClient {
     @SuppressLint("CheckResult")
     private JsonObject fetchCaptionandDepictionsFromMediaDetailResponse(MediaDetailResponse mediaDetailResponse) {
         JsonObject mediaDetails = new JsonObject();
-        if (mediaDetailResponse != null && mediaDetailResponse.getSuccess() != null && mediaDetailResponse.getSuccess() == 1 && mediaDetailResponse.getEntities() != null) {
+        if (isSuccess(mediaDetailResponse)) {
             Map<String, CommonsWikibaseItem> entities = mediaDetailResponse.getEntities();
             try {
                 Map.Entry<String, CommonsWikibaseItem> entry = entities.entrySet().iterator().next();
@@ -247,7 +234,6 @@ public class MediaClient {
                 try {
                     LinkedTreeMap statements = (LinkedTreeMap) commonsWikibaseItem.getStatements();
                     ArrayList<LinkedTreeMap> depictsItemList = (ArrayList<LinkedTreeMap>) statements.get(BuildConfig.DEPICTS_PROPERTY);
-                    String depictions = null;
                     JsonArray jsonArray = new JsonArray();
                     for (int i = 0; i < depictsItemList.size(); i++) {
                         LinkedTreeMap depictedItem = depictsItemList.get(i);
@@ -268,7 +254,6 @@ public class MediaClient {
             } catch (Exception e) {
                 JsonElement jsonElement = new JsonPrimitive(NO_CAPTION);
                 mediaDetails.add("Caption", jsonElement);
-                jsonElement = null;
                 jsonElement = new JsonPrimitive(NO_DEPICTION);
                 mediaDetails.add("Depiction", jsonElement);
             }

app/src/main/java/fr/free/nrw/commons/wikidata/WikidataEditService.java

@@ -1,5 +1,7 @@
 package fr.free.nrw.commons.wikidata;
 
+import static fr.free.nrw.commons.depictions.Media.DepictedImagesFragment.PAGE_ID_PREFIX;
+
 import android.annotation.SuppressLint;
 import android.content.Context;
 import androidx.annotation.NonNull;
@@ -198,7 +200,7 @@ public class WikidataEditService {
         String data = jsonData.toString();
 
         Observable.defer((Callable<ObservableSource<Boolean>>) () ->
-                wikiBaseClient.postEditEntity("M" + fileEntityId, data))
+                wikiBaseClient.postEditEntity(PAGE_ID_PREFIX + fileEntityId, data))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(success -> {

app/src/test/kotlin/fr/free/nrw/commons/depictions/DepictedImagesPresenterTest.kt

@@ -55,7 +55,8 @@ class DepictedImagesPresenterTest {
 
     @Test
     fun initList() {
-        Mockito.`when`(depictsClient?.fetchImagesForDepictedItem(ArgumentMatchers.anyString(), ArgumentMatchers.anyInt(), ArgumentMatchers.anyInt())).thenReturn(testObservable)
+        Mockito.`when`(depictsClient?.fetchImagesForDepictedItem(ArgumentMatchers.anyString(),
+            ArgumentMatchers.anyInt())).thenReturn(testObservable)
         depictedImagesPresenter?.initList("rabbit")
         depictedImagesPresenter?.handleSuccess(mediaList)
         verify(view)?.handleSuccess(mediaList)