set up WorkManager on demand to avoid slowing down starts

This also provides a convenient place to configure the debug logging.

app/proguard-rules.pro

@@ -4,13 +4,11 @@
 -keep class org.fdroid.fdroid.** {*;}
 -dontskipnonpubliclibraryclassmembers
 -dontwarn android.test.**
--dontwarn com.android.support.test.**
 
 -dontwarn javax.naming.**
 -dontwarn org.slf4j.**
 -dontnote org.apache.http.**
 -dontnote android.net.http.**
--dontnote android.support.**
 -dontnote **ILicensingService
 
 # Needed for espresso https://stackoverflow.com/a/21706087
@@ -49,3 +47,8 @@ public static final org.codehaus.jackson.annotate.JsonAutoDetect$Visibility *; }
 -keep public class your.class.** {
   *;
 }
+
+# This is necessary so that RemoteWorkManager can be initialized (also marked with @Keep)
+-keep class androidx.work.multiprocess.RemoteWorkManagerClient {
+    public <init>(...);
+}

app/src/main/AndroidManifest.xml

@@ -266,8 +266,11 @@
                 android:name=".AddRepoIntentService"
                 android:exported="false"/>
 
-
+        <provider
-        <!-- Warning: Please add all new services to HidingManager -->
+                android:name="androidx.work.impl.WorkManagerInitializer"
+                android:authorities="${applicationId}.workmanager-init"
+                android:exported="false"
+                tools:node="remove" />
 
         <activity
                 android:name=".views.main.MainActivity"

app/src/main/java/org/fdroid/fdroid/FDroidApp.java

@@ -46,11 +46,10 @@ import android.util.Log;
 import android.view.Display;
 import android.view.WindowManager;
 import android.widget.Toast;
-
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.collection.LongSparseArray;
 import androidx.core.content.ContextCompat;
-
 import com.nostra13.universalimageloader.cache.disc.DiskCache;
 import com.nostra13.universalimageloader.cache.disc.impl.UnlimitedDiskCache;
 import com.nostra13.universalimageloader.cache.disc.impl.ext.LruDiskCache;
@@ -58,7 +57,8 @@ import com.nostra13.universalimageloader.core.DefaultConfigurationFactory;
 import com.nostra13.universalimageloader.core.ImageLoader;
 import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
 import com.nostra13.universalimageloader.core.process.BitmapProcessor;
-
+import info.guardianproject.netcipher.NetCipher;
+import info.guardianproject.netcipher.proxy.OrbotHelper;
 import org.acra.ACRA;
 import org.acra.ReportField;
 import org.acra.ReportingInteractionMode;
@@ -82,17 +82,13 @@ import org.fdroid.fdroid.net.ImageLoaderForUIL;
 import org.fdroid.fdroid.panic.HidingManager;
 import org.fdroid.fdroid.work.CleanCacheWorker;
 
+import javax.microedition.khronos.opengles.GL10;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.security.Security;
 import java.util.List;
 import java.util.UUID;
 
-import javax.microedition.khronos.opengles.GL10;
-
-import info.guardianproject.netcipher.NetCipher;
-import info.guardianproject.netcipher.proxy.OrbotHelper;
-
 @ReportsCrashes(mailTo = BuildConfig.ACRA_REPORT_EMAIL,
         mode = ReportingInteractionMode.DIALOG,
         reportDialogClass = org.fdroid.fdroid.acra.CrashReportActivity.class,
@@ -113,7 +109,7 @@ import info.guardianproject.netcipher.proxy.OrbotHelper;
                 ReportField.STACK_TRACE,
         }
 )
-public class FDroidApp extends Application {
+public class FDroidApp extends Application implements androidx.work.Configuration.Provider {
 
     private static final String TAG = "FDroidApp";
     private static final String ACRA_ID = BuildConfig.APPLICATION_ID + ":acra";
@@ -654,7 +650,7 @@ public class FDroidApp extends Application {
 
     /**
      * Put proxy settings (or Tor settings) globally into effect based on whats configured in Preferences.
-     *
+     * <p>
      * Must be called on App startup and after every proxy configuration change.
      */
     public static void configureProxy(Preferences preferences) {
@@ -676,4 +672,26 @@ public class FDroidApp extends Application {
     public static Context getInstance() {
         return instance;
     }
+
+    /**
+     * Set up WorkManager on demand to avoid slowing down starts.
+     *
+     * @see CleanCacheWorker
+     * @see org.fdroid.fdroid.work.PopularityContestWorker
+     * @see org.fdroid.fdroid.work.UpdateWorker
+     * @see <a href="https://developer.android.com/codelabs/android-adv-workmanager#3">example</a>
+     */
+    @NonNull
+    @Override
+    public androidx.work.Configuration getWorkManagerConfiguration() {
+        if (BuildConfig.DEBUG) {
+            return new androidx.work.Configuration.Builder()
+                    .setMinimumLoggingLevel(Log.DEBUG)
+                    .build();
+        } else {
+            return new androidx.work.Configuration.Builder()
+                    .setMinimumLoggingLevel(Log.ERROR)
+                    .build();
+        }
+    }
 }