With changes for limited connection mode (#3934)

* With changed for limited connection mode

* Java docs

* With minor fix

* Fix cosmetic issues

* Fix ANR

* Add Unit test

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

@@ -36,6 +36,7 @@ import fr.free.nrw.commons.di.ApplicationlessInjection;
 import fr.free.nrw.commons.kvstore.JsonKvStore;
 import fr.free.nrw.commons.logging.FileLoggingTree;
 import fr.free.nrw.commons.logging.LogUtils;
+import fr.free.nrw.commons.media.CustomOkHttpNetworkFetcher;
 import fr.free.nrw.commons.settings.Prefs;
 import fr.free.nrw.commons.upload.FileUtils;
 import fr.free.nrw.commons.utils.ConfigUtils;
@@ -77,10 +78,19 @@ import timber.log.Timber;
 )
 
 public class CommonsApplication extends MultiDexApplication {
-    @Inject SessionManager sessionManager;
-    @Inject DBOpenHelper dbOpenHelper;
 
-    @Inject @Named("default_preferences") JsonKvStore defaultPrefs;
+  public static final String IS_LIMITED_CONNECTION_MODE_ENABLED = "is_limited_connection_mode_enabled";
+  @Inject
+  SessionManager sessionManager;
+  @Inject
+  DBOpenHelper dbOpenHelper;
+
+  @Inject
+  @Named("default_preferences")
+  JsonKvStore defaultPrefs;
+
+  @Inject
+  CustomOkHttpNetworkFetcher customOkHttpNetworkFetcher;
 
     /**
      * Constants begin
@@ -147,6 +157,7 @@ public class CommonsApplication extends MultiDexApplication {
 
 //        Set DownsampleEnabled to True to downsample the image in case it's heavy
         ImagePipelineConfig config = ImagePipelineConfig.newBuilder(this)
+                .setNetworkFetcher(customOkHttpNetworkFetcher)
                 .setDownsampleEnabled(true)
                 .build();
         try {

app/src/main/java/fr/free/nrw/commons/contributions/Contribution.kt

@@ -84,6 +84,7 @@ data class Contribution constructor(
         const val STATE_QUEUED = 2
         const val STATE_IN_PROGRESS = 3
         const val STATE_PAUSED = 4
+        const val STATE_QUEUED_LIMITED_CONNECTION_MODE=5
 
         /**
          * Formatting captions to the Wikibase format for sending labels

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

@@ -61,6 +61,9 @@ public abstract class ContributionDao {
   @Query("SELECT * from contribution WHERE pageId=:pageId")
   public abstract Contribution getContribution(String pageId);
 
+  @Query("SELECT * from contribution WHERE state=:state")
+  public abstract Single<List<Contribution>> getContribution(int state);
+
   @Query("UPDATE contribution SET state=:state WHERE state in (:toUpdateStates)")
   public abstract Single<Integer> updateStates(int state, int[] toUpdateStates);
 

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

@@ -65,6 +65,11 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
     this.contribution = contribution;
     this.position = position;
     titleView.setText(contribution.getMedia().getMostRelevantCaption());
+
+    imageView.getHierarchy().setPlaceholderImage(R.drawable.image_placeholder);
+    imageView.getHierarchy().setFailureImage(R.drawable.image_placeholder);
+
+
     final String imageSource = chooseImageSource(contribution.getMedia().getThumbUrl(),
         contribution.getLocalUri());
     if (!TextUtils.isEmpty(imageSource)) {
@@ -88,6 +93,7 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
         checkIfMediaExistsOnWikipediaPage(contribution);
         break;
       case Contribution.STATE_QUEUED:
+      case Contribution.STATE_QUEUED_LIMITED_CONNECTION_MODE:
         stateView.setVisibility(View.VISIBLE);
         progressView.setVisibility(View.GONE);
         stateView.setText(R.string.contribution_state_queued);

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

@@ -474,7 +474,7 @@ public class ContributionsFragment
     @Override
     public void retryUpload(Contribution contribution) {
         if (NetworkUtils.isInternetConnectionEstablished(getContext())) {
-            if (contribution.getState() == STATE_FAILED || contribution.getState() == STATE_PAUSED && null != uploadService) {
+            if (contribution.getState() == STATE_FAILED || contribution.getState() == STATE_PAUSED || contribution.getState()==Contribution.STATE_QUEUED_LIMITED_CONNECTION_MODE && null != uploadService) {
                 uploadService.queue(contribution);
                 Timber.d("Restarting for %s", contribution.toString());
             } else {

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

@@ -3,6 +3,8 @@ package fr.free.nrw.commons.contributions;
 import android.annotation.SuppressLint;
 import android.app.AlertDialog;
 import android.content.Intent;
+import android.os.Build.VERSION;
+import android.os.Build.VERSION_CODES;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.Menu;
@@ -10,6 +12,7 @@ import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.ImageView;
+import android.widget.Switch;
 import android.widget.TextView;
 import androidx.annotation.Nullable;
 import androidx.core.view.GravityCompat;
@@ -21,6 +24,7 @@ import androidx.viewpager.widget.ViewPager;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import com.google.android.material.tabs.TabLayout;
+import fr.free.nrw.commons.CommonsApplication;
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.auth.SessionManager;
 import fr.free.nrw.commons.location.LocationServiceManager;
@@ -33,6 +37,7 @@ import fr.free.nrw.commons.quiz.QuizChecker;
 import fr.free.nrw.commons.theme.NavigationBaseActivity;
 import fr.free.nrw.commons.upload.UploadService;
 import fr.free.nrw.commons.utils.ViewUtil;
+import fr.free.nrw.commons.utils.ViewUtilWrapper;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.schedulers.Schedulers;
 import java.util.List;
@@ -56,6 +61,8 @@ public class MainActivity extends NavigationBaseActivity implements FragmentMana
     NotificationController notificationController;
     @Inject
     QuizChecker quizChecker;
+    @Inject
+    ViewUtilWrapper viewUtilWrapper;
 
 
     public ContributionsActivityPagerAdapter contributionsActivityPagerAdapter;
@@ -70,6 +77,7 @@ public class MainActivity extends NavigationBaseActivity implements FragmentMana
     private TextView notificationCount;
     private NearbyParentFragment nearbyParentFragment;
 
+    @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_contributions);
@@ -280,9 +288,25 @@ public class MainActivity extends NavigationBaseActivity implements FragmentMana
         this.menu = menu;
         updateMenuItem();
         setNotificationCount();
+
+        updateLimitedConnectionToggle(menu);
+
         return true;
     }
 
+    private void updateLimitedConnectionToggle(Menu menu) {
+        MenuItem checkable = menu.findItem(R.id.toggle_limited_connection_mode);
+        boolean isEnabled = defaultKvStore
+            .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED, false);
+
+        checkable.setChecked(isEnabled);
+        final Switch switchToggleLimitedConnectionMode = checkable.getActionView()
+            .findViewById(R.id.switch_toggle_limited_connection_mode);
+        switchToggleLimitedConnectionMode.setChecked(isEnabled);
+        switchToggleLimitedConnectionMode.setOnCheckedChangeListener(
+            (buttonView, isChecked) -> toggleLimitedConnectionMode());
+    }
+
     @SuppressLint("CheckResult")
     private void setNotificationCount() {
         compositeDisposable.add(notificationController.getNotifications(false)
@@ -339,6 +363,27 @@ public class MainActivity extends NavigationBaseActivity implements FragmentMana
         }
     }
 
+    private void toggleLimitedConnectionMode() {
+        defaultKvStore.putBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED,
+            !defaultKvStore
+                .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED, false));
+        if (defaultKvStore
+            .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED, false)) {
+            viewUtilWrapper
+                .showShortToast(getBaseContext(), getString(R.string.limited_connection_enabled));
+        } else {
+            Intent intent = new Intent(this, UploadService.class);
+            intent.setAction(UploadService.PROCESS_PENDING_LIMITED_CONNECTION_MODE_UPLOADS);
+            if (VERSION.SDK_INT >= VERSION_CODES.O) {
+                startForegroundService(intent);
+            } else {
+                startService(intent);
+            }
+            viewUtilWrapper
+                .showShortToast(getBaseContext(), getString(R.string.limited_connection_disabled));
+        }
+    }
+
     public class ContributionsActivityPagerAdapter extends FragmentPagerAdapter {
         FragmentManager fragmentManager;
 

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

@@ -0,0 +1,229 @@
+package fr.free.nrw.commons.media;
+
+import android.net.Uri;
+import android.os.Looper;
+import android.os.SystemClock;
+import androidx.annotation.Nullable;
+import com.facebook.imagepipeline.common.BytesRange;
+import com.facebook.imagepipeline.image.EncodedImage;
+import com.facebook.imagepipeline.producers.BaseNetworkFetcher;
+import com.facebook.imagepipeline.producers.BaseProducerContextCallbacks;
+import com.facebook.imagepipeline.producers.Consumer;
+import com.facebook.imagepipeline.producers.FetchState;
+import com.facebook.imagepipeline.producers.NetworkFetcher;
+import com.facebook.imagepipeline.producers.ProducerContext;
+import fr.free.nrw.commons.CommonsApplication;
+import fr.free.nrw.commons.kvstore.JsonKvStore;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.Executor;
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Singleton;
+import okhttp3.CacheControl;
+import okhttp3.Call;
+import okhttp3.OkHttpClient;
+import okhttp3.Request;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+import timber.log.Timber;
+
+// Custom implementation of Fresco's Network fetcher to skip downloading of images when limited connection mode is enabled
+// https://github.com/facebook/fresco/blob/master/imagepipeline-backends/imagepipeline-okhttp3/src/main/java/com/facebook/imagepipeline/backends/okhttp3/OkHttpNetworkFetcher.java
+@Singleton
+public class CustomOkHttpNetworkFetcher
+    extends BaseNetworkFetcher<CustomOkHttpNetworkFetcher.OkHttpNetworkFetchState> {
+
+  private static final String QUEUE_TIME = "queue_time";
+  private static final String FETCH_TIME = "fetch_time";
+  private static final String TOTAL_TIME = "total_time";
+  private static final String IMAGE_SIZE = "image_size";
+  private final Call.Factory mCallFactory;
+  private final @Nullable
+  CacheControl mCacheControl;
+  private Executor mCancellationExecutor;
+  private JsonKvStore defaultKvStore;
+
+  /**
+   * @param okHttpClient client to use
+   */
+  @Inject
+  public CustomOkHttpNetworkFetcher(OkHttpClient okHttpClient,
+      @Named("default_preferences") JsonKvStore defaultKvStore) {
+    this(okHttpClient, okHttpClient.dispatcher().executorService(), defaultKvStore);
+  }
+
+  /**
+   * @param callFactory          custom {@link Call.Factory} for fetching image from the network
+   * @param cancellationExecutor executor on which fetching cancellation is performed if
+   *                             cancellation is requested from the UI Thread
+   */
+  public CustomOkHttpNetworkFetcher(Call.Factory callFactory, Executor cancellationExecutor,
+      JsonKvStore defaultKvStore) {
+    this(callFactory, cancellationExecutor, defaultKvStore, true);
+  }
+
+  /**
+   * @param callFactory          custom {@link Call.Factory} for fetching image from the network
+   * @param cancellationExecutor executor on which fetching cancellation is performed if
+   *                             cancellation is requested from the UI Thread
+   * @param disableOkHttpCache   true if network requests should not be cached by OkHttp
+   */
+  public CustomOkHttpNetworkFetcher(
+      Call.Factory callFactory, Executor cancellationExecutor, JsonKvStore defaultKvStore,
+      boolean disableOkHttpCache) {
+    this.defaultKvStore = defaultKvStore;
+    mCallFactory = callFactory;
+    mCancellationExecutor = cancellationExecutor;
+    mCacheControl = disableOkHttpCache ? new CacheControl.Builder().noStore().build() : null;
+  }
+
+  @Override
+  public OkHttpNetworkFetchState createFetchState(
+      Consumer<EncodedImage> consumer, ProducerContext context) {
+    return new OkHttpNetworkFetchState(consumer, context);
+  }
+
+  @Override
+  public void fetch(
+      final OkHttpNetworkFetchState fetchState, final NetworkFetcher.Callback callback) {
+    fetchState.submitTime = SystemClock.elapsedRealtime();
+    final Uri uri = fetchState.getUri();
+
+    try {
+      if (defaultKvStore
+          .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED, false)) {
+        Timber.d("Skipping loading of image as limited connection mode is enabled");
+        callback.onFailure(
+            new Exception("Failing image request as limited connection mode is enabled"));
+        return;
+      }
+      final Request.Builder requestBuilder = new Request.Builder().url(uri.toString()).get();
+
+      if (mCacheControl != null) {
+        requestBuilder.cacheControl(mCacheControl);
+      }
+
+      final BytesRange bytesRange = fetchState.getContext().getImageRequest().getBytesRange();
+      if (bytesRange != null) {
+        requestBuilder.addHeader("Range", bytesRange.toHttpRangeHeaderValue());
+      }
+
+      fetchWithRequest(fetchState, callback, requestBuilder.build());
+    } catch (Exception e) {
+      // handle error while creating the request
+      callback.onFailure(e);
+    }
+  }
+
+  @Override
+  public void onFetchCompletion(OkHttpNetworkFetchState fetchState, int byteSize) {
+    fetchState.fetchCompleteTime = SystemClock.elapsedRealtime();
+  }
+
+  @Override
+  public Map<String, String> getExtraMap(OkHttpNetworkFetchState fetchState, int byteSize) {
+    Map<String, String> extraMap = new HashMap<>(4);
+    extraMap.put(QUEUE_TIME, Long.toString(fetchState.responseTime - fetchState.submitTime));
+    extraMap.put(FETCH_TIME, Long.toString(fetchState.fetchCompleteTime - fetchState.responseTime));
+    extraMap.put(TOTAL_TIME, Long.toString(fetchState.fetchCompleteTime - fetchState.submitTime));
+    extraMap.put(IMAGE_SIZE, Integer.toString(byteSize));
+    return extraMap;
+  }
+
+  protected void fetchWithRequest(
+      final OkHttpNetworkFetchState fetchState,
+      final NetworkFetcher.Callback callback,
+      final Request request) {
+    final Call call = mCallFactory.newCall(request);
+
+    fetchState
+        .getContext()
+        .addCallbacks(
+            new BaseProducerContextCallbacks() {
+              @Override
+              public void onCancellationRequested() {
+                if (Looper.myLooper() != Looper.getMainLooper()) {
+                  call.cancel();
+                } else {
+                  mCancellationExecutor.execute(
+                      new Runnable() {
+                        @Override
+                        public void run() {
+                          call.cancel();
+                        }
+                      });
+                }
+              }
+            });
+
+    call.enqueue(
+        new okhttp3.Callback() {
+          @Override
+          public void onResponse(Call call, Response response) throws IOException {
+            fetchState.responseTime = SystemClock.elapsedRealtime();
+            final ResponseBody body = response.body();
+            try {
+              if (!response.isSuccessful()) {
+                handleException(
+                    call, new IOException("Unexpected HTTP code " + response), callback);
+                return;
+              }
+
+              BytesRange responseRange =
+                  BytesRange.fromContentRangeHeader(response.header("Content-Range"));
+              if (responseRange != null
+                  && !(responseRange.from == 0
+                  && responseRange.to == BytesRange.TO_END_OF_CONTENT)) {
+                // Only treat as a partial image if the range is not all of the content
+                fetchState.setResponseBytesRange(responseRange);
+                fetchState.setOnNewResultStatusFlags(Consumer.IS_PARTIAL_RESULT);
+              }
+
+              long contentLength = body.contentLength();
+              if (contentLength < 0) {
+                contentLength = 0;
+              }
+              callback.onResponse(body.byteStream(), (int) contentLength);
+            } catch (Exception e) {
+              handleException(call, e, callback);
+            } finally {
+              body.close();
+            }
+          }
+
+          @Override
+          public void onFailure(Call call, IOException e) {
+            handleException(call, e, callback);
+          }
+        });
+  }
+
+  /**
+   * Handles exceptions.
+   *
+   * <p>OkHttp notifies callers of cancellations via an IOException. If IOException is caught after
+   * request cancellation, then the exception is interpreted as successful cancellation and
+   * onCancellation is called. Otherwise onFailure is called.
+   */
+  private void handleException(final Call call, final Exception e, final Callback callback) {
+    if (call.isCanceled()) {
+      callback.onCancellation();
+    } else {
+      callback.onFailure(e);
+    }
+  }
+
+  public static class OkHttpNetworkFetchState extends FetchState {
+
+    public long submitTime;
+    public long responseTime;
+    public long fetchCompleteTime;
+
+    public OkHttpNetworkFetchState(
+        Consumer<EncodedImage> consumer, ProducerContext producerContext) {
+      super(consumer, producerContext);
+    }
+  }
+}

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

@@ -429,6 +429,13 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment implements
      * - when the high resolution image is available, it replaces the low resolution image
      */
     private void setupImageView() {
+
+        image.getHierarchy().setPlaceholderImage(R.drawable.image_placeholder);
+        image.getHierarchy().setFailureImage(R.drawable.image_placeholder);
+
+        imageLandscape.getHierarchy().setPlaceholderImage(R.drawable.image_placeholder);
+        imageLandscape.getHierarchy().setFailureImage(R.drawable.image_placeholder);
+
         DraweeController controller = Fresco.newDraweeControllerBuilder()
                 .setLowResImageRequest(ImageRequest.fromUri(media.getThumbUrl()))
                 .setImageRequest(ImageRequest.fromUri(media.getImageUrl()))

app/src/main/java/fr/free/nrw/commons/upload/UploadPresenter.java

@@ -1,22 +1,21 @@
 package fr.free.nrw.commons.upload;
 
 import android.annotation.SuppressLint;
-
+import fr.free.nrw.commons.CommonsApplication;
-import java.lang.reflect.Proxy;
-import java.util.ArrayList;
-import java.util.List;
-
-import javax.inject.Inject;
-import javax.inject.Singleton;
-
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.contributions.Contribution;
 import fr.free.nrw.commons.filepicker.UploadableFile;
+import fr.free.nrw.commons.kvstore.JsonKvStore;
 import fr.free.nrw.commons.repository.UploadRepository;
 import io.reactivex.Observer;
 import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.disposables.Disposable;
 import io.reactivex.schedulers.Schedulers;
+import java.lang.reflect.Proxy;
+import java.util.List;
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Singleton;
 import timber.log.Timber;
 
 /**
@@ -29,13 +28,16 @@ public class UploadPresenter implements UploadContract.UserActionListener {
             UploadContract.View.class.getClassLoader(),
             new Class[]{UploadContract.View.class}, (proxy, method, methodArgs) -> null);
     private final UploadRepository repository;
+    private final JsonKvStore defaultKvStore;
     private UploadContract.View view = DUMMY;
 
     private CompositeDisposable compositeDisposable;
 
     @Inject
-    UploadPresenter(UploadRepository uploadRepository) {
+    UploadPresenter(UploadRepository uploadRepository,
+        @Named("default_preferences") JsonKvStore defaultKvStore) {
         this.repository = uploadRepository;
+        this.defaultKvStore = defaultKvStore;
         compositeDisposable = new CompositeDisposable();
     }
 
@@ -54,7 +56,14 @@ public class UploadPresenter implements UploadContract.UserActionListener {
                         @Override
                         public void onSubscribe(Disposable d) {
                             view.showProgress(false);
-                            view.showMessage(R.string.uploading_started);
+                            if (defaultKvStore
+                                .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED,
+                                    false)) {
+                                view.showMessage(R.string.uploading_queued);
+                            } else {
+                                view.showMessage(R.string.uploading_started);
+                            }
+
                             compositeDisposable.add(d);
                         }
 

app/src/main/java/fr/free/nrw/commons/upload/UploadService.java

@@ -21,13 +21,17 @@ import fr.free.nrw.commons.contributions.ContributionDao;
 import fr.free.nrw.commons.contributions.MainActivity;
 import fr.free.nrw.commons.di.CommonsApplicationModule;
 import fr.free.nrw.commons.di.CommonsDaggerService;
+import fr.free.nrw.commons.kvstore.JsonKvStore;
 import fr.free.nrw.commons.media.MediaClient;
 import fr.free.nrw.commons.utils.ViewUtil;
 import fr.free.nrw.commons.wikidata.WikidataEditService;
+import io.reactivex.Completable;
 import io.reactivex.Observable;
+import io.reactivex.ObservableSource;
 import io.reactivex.Scheduler;
 import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.functions.Consumer;
+import io.reactivex.functions.Function;
 import io.reactivex.processors.PublishProcessor;
 import io.reactivex.schedulers.Schedulers;
 import java.io.IOException;
@@ -50,6 +54,7 @@ public class UploadService extends CommonsDaggerService {
       .asList("uploadstash-file-not-found", "stashfailed", "verification-error", "chunk-too-small");
 
   public static final String ACTION_START_SERVICE = EXTRA_PREFIX + ".upload";
+  public static final String PROCESS_PENDING_LIMITED_CONNECTION_MODE_UPLOADS = EXTRA_PREFIX + "process_limited_connection_mode_uploads";
   public static final String EXTRA_FILES = EXTRA_PREFIX + ".files";
   @Inject
   WikidataEditService wikidataEditService;
@@ -67,6 +72,9 @@ public class UploadService extends CommonsDaggerService {
   @Inject
   @Named(CommonsApplicationModule.IO_THREAD)
   Scheduler ioThreadScheduler;
+  @Inject
+  @Named("default_preferences")
+  public JsonKvStore defaultKvStore;
 
   private NotificationManagerCompat notificationManager;
   private NotificationCompat.Builder curNotification;
@@ -203,11 +211,21 @@ public class UploadService extends CommonsDaggerService {
   private boolean freshStart = true;
 
   public void queue(Contribution contribution) {
+    if (defaultKvStore
+        .getBoolean(CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED, false)) {
+      contribution.setState(Contribution.STATE_QUEUED_LIMITED_CONNECTION_MODE);
+      contributionDao.save(contribution)
+          .subscribeOn(ioThreadScheduler)
+          .subscribe();
+      return;
+    }
     contributionsToUpload.offer(contribution);
   }
 
   @Override
   public int onStartCommand(Intent intent, int flags, int startId) {
+    startForeground(NOTIFICATION_UPLOAD_IN_PROGRESS,
+        curNotification.setContentText(getText(R.string.starting_uploads)).build());
     if (ACTION_START_SERVICE.equals(intent.getAction()) && freshStart) {
       compositeDisposable.add(contributionDao.updateStates(Contribution.STATE_FAILED,
           new int[]{Contribution.STATE_QUEUED, Contribution.STATE_IN_PROGRESS})
@@ -215,7 +233,14 @@ public class UploadService extends CommonsDaggerService {
           .subscribeOn(ioThreadScheduler)
           .subscribe());
       freshStart = false;
-    }
+    } else if (PROCESS_PENDING_LIMITED_CONNECTION_MODE_UPLOADS.equals(intent.getAction())) {
+        contributionDao.getContribution(Contribution.STATE_QUEUED_LIMITED_CONNECTION_MODE)
+            .flatMapObservable(
+                (Function<List<Contribution>, ObservableSource<Contribution>>) contributions -> Observable.fromIterable(contributions))
+            .concatMapCompletable(contribution -> Completable.fromAction(() -> queue(contribution)))
+        .subscribeOn(ioThreadScheduler)
+        .subscribe();
+      }
     return START_REDELIVER_INTENT;
   }
 

app/src/main/res/layout/menu_switch.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Switch xmlns:android="http://schemas.android.com/apk/res/android"
+  android:layout_width="wrap_content"
+  android:layout_height="match_parent"
+  android:id="@+id/switch_toggle_limited_connection_mode"/>

app/src/main/res/menu/contribution_activity_notification_menu.xml

@@ -1,5 +1,12 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <item android:id="@+id/toggle_limited_connection_mode"
+      android:title="@string/limited_connection"
+      app:showAsAction="always"
+      android:checkable="true"
+      app:actionLayout="@layout/menu_switch"
+      />
     <item android:id="@+id/notifications"
         android:title="@string/notifications"
         app:showAsAction="ifRoom|withText"

app/src/main/res/values/strings.xml

@@ -10,6 +10,7 @@
     <item quantity="one">(%1$d)</item>
     <item quantity="other">(%1$d)</item>
   </plurals>
+  <string name="starting_uploads"> Starting Uploads</string>
   <plurals name="starting_multiple_uploads">
     <item quantity="one">Starting %1$d upload</item>
     <item quantity="other">Starting %1$d uploads</item>
@@ -54,6 +55,7 @@
   <string name="upload_failed">File not found. Please try another file.</string>
   <string name="authentication_failed">Authentication failed, please login again</string>
   <string name="uploading_started">Upload started!</string>
+  <string name="uploading_queued">Upload queued (limited connection mode enabled)</string>
   <string name="upload_completed_notification_title">%1$s uploaded!</string>
   <string name="upload_completed_notification_text">Tap to view your upload</string>
   <string name="upload_progress_notification_title_start">Starting %1$s upload</string>
@@ -692,4 +694,7 @@ Upload your first media by tapping on the add button.</string>
   <string name="mapbox_telemetry">Telemetry Opt Out</string>
   <string name="telemetry_opt_out_summary">Send anonymized location and usage data to Mapbox when using Nearby feature</string>
   <string name="map_attribution" translatable="false"><![CDATA[&#169; <a href="https://www.mapbox.com/about/maps/">Mapbox</a> &#169; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> <a href="https://www.mapbox.com/map-feedback/">Improve this map</a>]]></string>
+  <string name="limited_connection_enabled">Limited connection mode enabled!</string>
+  <string name="limited_connection_disabled">Limited connection mode disabled. Pending uploads will resume now.</string>
+  <string name="limited_connection">Limited Connection</string>
 </resources>

app/src/test/kotlin/fr/free/nrw/commons/upload/UploadPresenterTest.kt

@@ -1,8 +1,10 @@
 package fr.free.nrw.commons.upload
 
 import com.nhaarman.mockitokotlin2.verify
+import fr.free.nrw.commons.CommonsApplication
 import fr.free.nrw.commons.contributions.Contribution
 import fr.free.nrw.commons.filepicker.UploadableFile
+import fr.free.nrw.commons.kvstore.JsonKvStore
 import fr.free.nrw.commons.repository.UploadRepository
 import io.reactivex.Observable
 import org.junit.Before
@@ -27,6 +29,9 @@ class UploadPresenterTest {
     @Mock
     lateinit var contribution: Contribution
 
+    @Mock
+    lateinit var defaultKvStore: JsonKvStore
+
     @Mock
     private lateinit var uploadableFile: UploadableFile
 
@@ -65,6 +70,22 @@ class UploadPresenterTest {
         verify(repository).buildContributions()
     }
 
+    @Test
+    fun handleSubmitTestUserLoggedInAndLimitedConnectionOn() {
+        `when`(
+            defaultKvStore
+                .getBoolean(
+                    CommonsApplication.IS_LIMITED_CONNECTION_MODE_ENABLED,
+                    false
+                )).thenReturn(true)
+        `when`(view.isLoggedIn).thenReturn(true)
+        uploadPresenter.handleSubmit()
+        verify(view).isLoggedIn
+        verify(view).showProgress(true)
+        verify(repository).buildContributions()
+        verify(repository).buildContributions()
+    }
+
     /**
      * unit test case for method UploadPresenter.handleSubmit
      */