Migrate network tasks to RxJava

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

@@ -23,7 +23,6 @@ import com.jakewharton.rxbinding2.view.RxView;
 import com.jakewharton.rxbinding2.widget.RxTextView;
 import com.pedrogomez.renderers.RVRendererAdapter;
 
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Date;
@@ -36,10 +35,8 @@ import butterknife.ButterKnife;
 import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.data.Category;
-import fr.free.nrw.commons.mwapi.MediaWikiApi;
 import fr.free.nrw.commons.upload.MwVolleyApi;
 import io.reactivex.Observable;
-import io.reactivex.Single;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.schedulers.Schedulers;
 import timber.log.Timber;
@@ -194,7 +191,7 @@ public class CategorizationFragment extends Fragment {
             rootView.requestFocus();
             rootView.setOnKeyListener((v, keyCode, event) -> {
                 if (event.getAction() == ACTION_UP && keyCode == KEYCODE_BACK) {
-                    backButtonDialog();
+                    showBackButtonDialog();
                     return true;
                 }
                 return false;
@@ -224,25 +221,12 @@ public class CategorizationFragment extends Fragment {
     public boolean onOptionsItemSelected(MenuItem menuItem) {
         switch (menuItem.getItemId()) {
             case R.id.menu_save_categories:
-                //If no categories selected, display warning to user
+                if (selectedCategories.size() > 0) {
-                if (selectedCategories.size() == 0) {
+                    //Some categories selected, proceed to submission
-                    new AlertDialog.Builder(getActivity())
-                            .setMessage("Images without categories are rarely usable. "
-                                    + "Are you sure you want to submit without selecting "
-                                    + "categories?")
-                            .setTitle("No Categories Selected")
-                            .setPositiveButton("No, go back", (dialog, id) -> {
-                                //Exit menuItem so user can select their categories
-                            })
-                            .setNegativeButton("Yes, submit", (dialog, id) -> {
-                                //Proceed to submission
                     onCategoriesSaveHandler.onCategoriesSave(getStringList(selectedCategories));
-                            })
-                            .create()
-                            .show();
                 } else {
-                    //Proceed to submission
+                    //No categories selected, prompt the user to select some
-                    onCategoriesSaveHandler.onCategoriesSave(getStringList(selectedCategories));
+                    showConfirmationDialog();
                 }
                 return true;
             default:
@@ -271,7 +255,7 @@ public class CategorizationFragment extends Fragment {
         return Observable.fromIterable(
                 MwVolleyApi.GpsCatExists.getGpsCatExists() ?
                         MwVolleyApi.getGpsCat() : new ArrayList<>())
-                .map(s -> new CategoryItem(s, false));
+                .map(name -> new CategoryItem(name, false));
     }
 
     private Observable<CategoryItem> titleCategories() {
@@ -279,10 +263,9 @@ public class CategorizationFragment extends Fragment {
         SharedPreferences titleDesc = PreferenceManager.getDefaultSharedPreferences(getActivity());
         String title = titleDesc.getString("Title", "");
 
-        return Observable.just(title)
+        return CommonsApplication.getInstance().getMWApi()
-                .observeOn(Schedulers.io())
+                .searchTitles(title, SEARCH_CATS_LIMIT)
-                .flatMapIterable(s -> titleCatQuery(s))
+                .map(name -> new CategoryItem(name, false));
-                .map(s -> new CategoryItem(s, false));
     }
 
     private Observable<CategoryItem> recentCategories() {
@@ -291,62 +274,35 @@ public class CategorizationFragment extends Fragment {
     }
 
     private Observable<CategoryItem> search(String term) {
-        return Single.just(term)
-                .map(s -> {
         //If user hasn't typed anything in yet, get GPS and recent items
-                    if (TextUtils.isEmpty(s)) {
+        if (TextUtils.isEmpty(term)) {
-                        return new ArrayList<String>();
+            return Observable.empty();
         }
 
         //if user types in something that is in cache, return cached category
-                    if (categoriesCache.containsKey(s)) {
+        if (categoriesCache.containsKey(term)) {
-                        return categoriesCache.get(s);
+            return Observable.fromIterable(categoriesCache.get(term))
+                    .map(name -> new CategoryItem(name, false));
         }
 
         //otherwise if user has typed something in that isn't in cache, search API for matching categories
-                    //URL: https://commons.wikimedia.org/w/api.php?action=query&list=allcategories&acprefix=filter&aclimit=25
+        return CommonsApplication.getInstance().getMWApi()
-                    MediaWikiApi api = CommonsApplication.getInstance().getMWApi();
+                .allCategories(term, SEARCH_CATS_LIMIT)
-                    List<String> categories = new ArrayList<>();
+                .map(name -> new CategoryItem(name, false));
-                    try {
-                        categories = api.allCategories(SEARCH_CATS_LIMIT, s);
-                        Timber.d("Prefix URL filter %s", categories);
-                    } catch (IOException e) {
-                        Timber.e(e, "IO Exception: ");
-                        //Return empty arraylist
-                        return categories;
-                    }
-
-                    Timber.d("Found categories from Prefix search, waiting for filter");
-                    return categories;
-                })
-                .flatMapObservable(Observable::fromIterable)
-                .map(s -> new CategoryItem(s, false));
     }
 
     private Observable<CategoryItem> search2(String term) {
-        return Single.just(term)
-                .map(s -> {
         //If user hasn't typed anything in yet, get GPS and recent items
-                    if (TextUtils.isEmpty(s)) {
+        if (TextUtils.isEmpty(term)) {
-                        return new ArrayList<String>();
+            return Observable.empty();
         }
 
-                    MediaWikiApi api = CommonsApplication.getInstance().getMWApi();
+        return CommonsApplication.getInstance().getMWApi()
-
+                .searchCategories(term, SEARCH_CATS_LIMIT)
-                    //URL https://commons.wikimedia.org/w/api.php?action=query&format=xml&list=search&srwhat=text&srenablerewrites=1&srnamespace=14&srlimit=10&srsearch=
-                    try {
-                        return api.searchCategories(SEARCH_CATS_LIMIT, term);
-                    } catch (IOException e) {
-                        Timber.e(e, "IO Exception: ");
-                        return new ArrayList<String>();
-                    }
-                })
-                .flatMapObservable(Observable::fromIterable)
                 .map(s -> new CategoryItem(s, false));
     }
 
     private boolean containsYear(String items) {
-
         //Check for current and previous year to exclude these categories from removal
         Calendar now = Calendar.getInstance();
         int year = now.get(Calendar.YEAR);
@@ -356,7 +312,6 @@ public class CategorizationFragment extends Fragment {
         String prevYearInString = String.valueOf(prevYear);
         Timber.d("Previous year: %s", prevYearInString);
 
-
         //Check if s contains a 4-digit word anywhere within the string (.* is wildcard)
         //And that s does not equal the current year or previous year
         //And if it is an irrelevant category such as Media_needing_categories_as_of_16_June_2017(Issue #750)
@@ -368,7 +323,7 @@ public class CategorizationFragment extends Fragment {
         return selectedCategories.size();
     }
 
-    public void backButtonDialog() {
+    public void showBackButtonDialog() {
         new AlertDialog.Builder(getActivity())
                 .setMessage("Are you sure you want to go back? The image will not "
                         + "have any categories saved.")
@@ -380,4 +335,21 @@ public class CategorizationFragment extends Fragment {
                 .create()
                 .show();
     }
+
+    public void showConfirmationDialog() {
+        new AlertDialog.Builder(getActivity())
+                .setMessage("Images without categories are rarely usable. "
+                        + "Are you sure you want to submit without selecting "
+                        + "categories?")
+                .setTitle("No Categories Selected")
+                .setPositiveButton("No, go back", (dialog, id) -> {
+                    //Exit menuItem so user can select their categories
+                })
+                .setNegativeButton("Yes, submit", (dialog, id) -> {
+                    //Proceed to submission
+                    onCategoriesSaveHandler.onCategoriesSave(getStringList(selectedCategories));
+                })
+                .create()
+                .show();
+    }
 }

app/src/main/java/fr/free/nrw/commons/mwapi/ApacheHttpClientMediaWikiApi.java

@@ -35,6 +35,7 @@ import fr.free.nrw.commons.BuildConfig;
 import fr.free.nrw.commons.PageTitle;
 import fr.free.nrw.commons.Utils;
 import in.yuvi.http.fluent.Http;
+import io.reactivex.Observable;
 import io.reactivex.Single;
 import timber.log.Timber;
 
@@ -205,8 +206,11 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
 
     @Override
     @NonNull
-    public List<String> searchCategories(int searchCatsLimit, String filterValue) throws IOException {
+    public Observable<String> searchCategories(String filterValue, int searchCatsLimit) {
-        List<ApiResult> categoryNodes = api.action("query")
+        return Single.fromCallable(() -> {
+            List<ApiResult> categoryNodes = null;
+            try {
+                categoryNodes = api.action("query")
                         .param("format", "xml")
                         .param("list", "search")
                         .param("srwhat", "text")
@@ -215,9 +219,12 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
                         .param("srsearch", filterValue)
                         .get()
                         .getNodes("/api/query/search/p/@title");
+            } catch (IOException e) {
+                Timber.e("Failed to obtain searchCategories", e);
+            }
 
             if (categoryNodes == null) {
-            return Collections.emptyList();
+                return new ArrayList<String>();
             }
 
             List<String> categories = new ArrayList<>();
@@ -228,20 +235,28 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
             }
 
             return categories;
+        })
+                .flatMapObservable(list -> Observable.fromIterable(list));
     }
 
     @Override
     @NonNull
-    public List<String> allCategories(int searchCatsLimit, String filterValue) throws IOException {
+    public Observable<String> allCategories(String filterValue, int searchCatsLimit) {
-        ArrayList<ApiResult> categoryNodes = api.action("query")
+        return Single.fromCallable(() -> {
+            ArrayList<ApiResult> categoryNodes = null;
+            try {
+                categoryNodes = api.action("query")
                         .param("list", "allcategories")
                         .param("acprefix", filterValue)
                         .param("aclimit", searchCatsLimit)
                         .get()
                         .getNodes("/api/query/allcategories/c");
+            } catch (IOException e) {
+                Timber.e("Failed to obtain allCategories", e);
+            }
 
             if (categoryNodes == null) {
-            return Collections.emptyList();
+                return new ArrayList<String>();
             }
 
             List<String> categories = new ArrayList<>();
@@ -250,12 +265,18 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
             }
 
             return categories;
+        })
+                .flatMapObservable(list -> Observable.fromIterable(list));
     }
 
     @Override
     @NonNull
-    public List<String> searchTitles(int searchCatsLimit, String title) throws IOException {
+    public Observable<String> searchTitles(String title, int searchCatsLimit) {
-        ArrayList<ApiResult> categoryNodes = api.action("query")
+        return Single.fromCallable(() -> {
+            ArrayList<ApiResult> categoryNodes = null;
+
+            try {
+                categoryNodes = api.action("query")
                         .param("format", "xml")
                         .param("list", "search")
                         .param("srwhat", "text")
@@ -264,6 +285,10 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
                         .param("srsearch", title)
                         .get()
                         .getNodes("/api/query/search/p/@title");
+            } catch (IOException e) {
+                Timber.e("Failed to obtain searchTitles", e);
+                return new ArrayList();
+            }
 
             if (categoryNodes == null) {
                 return Collections.emptyList();
@@ -277,6 +302,8 @@ public class ApacheHttpClientMediaWikiApi implements MediaWikiApi {
             }
 
             return titleCategories;
+        })
+                .flatMapObservable(list -> Observable.fromIterable(list));
     }
 
     @Override

app/src/main/java/fr/free/nrw/commons/mwapi/MediaWikiApi.java

@@ -7,6 +7,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
 
+import io.reactivex.Observable;
 import io.reactivex.Single;
 
 public interface MediaWikiApi {
@@ -38,13 +39,13 @@ public interface MediaWikiApi {
     MediaResult fetchMediaByFilename(String filename) throws IOException;
 
     @NonNull
-    List<String> searchCategories(int searchCatsLimit, String filterValue) throws IOException;
+    Observable<String> searchCategories(String filterValue, int searchCatsLimit);
 
     @NonNull
-    List<String> allCategories(int searchCatsLimit, String filter) throws IOException;
+    Observable<String> allCategories(String filter, int searchCatsLimit);
 
     @NonNull
-    List<String> searchTitles(int searchCatsLimit, String title) throws IOException;
+    Observable<String> searchTitles(String title, int searchCatsLimit);
 
     @Nullable
     String revisionsByFilename(String filename) throws IOException;