Move import/export to its own module (#6986)

Also clean up ImportExportPreferencesFragment a bit.

app/build.gradle

@@ -86,6 +86,7 @@ dependencies {
     implementation project(':playback:base')
     implementation project(':playback:cast')
     implementation project(':storage:database')
+    implementation project(':storage:importexport')
     implementation project(':storage:preferences')
     implementation project(':ui:app-start-intent')
     implementation project(':ui:common')

app/src/androidTest/java/de/test/antennapod/util/syndication/feedgenerator/Rss2Generator.java

@@ -6,13 +6,15 @@ import org.xmlpull.v1.XmlSerializer;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.text.SimpleDateFormat;
 import java.util.ArrayList;
+import java.util.Date;
+import java.util.Locale;
 
 import de.danoeh.antennapod.model.feed.Feed;
 import de.danoeh.antennapod.model.feed.FeedFunding;
 import de.danoeh.antennapod.model.feed.FeedItem;
 import de.danoeh.antennapod.parser.feed.namespace.PodcastIndex;
-import de.danoeh.antennapod.core.util.DateFormatter;
 
 /**
  * Creates RSS 2.0 feeds. See FeedGenerator for more information.
@@ -98,7 +100,7 @@ public class Rss2Generator implements FeedGenerator {
                 }
                 if (item.getPubDate() != null) {
                     xml.startTag(null, "pubDate");
-                    xml.text(DateFormatter.formatRfc822Date(item.getPubDate()));
+                    xml.text(formatRfc822Date(item.getPubDate()));
                     xml.endTag(null, "pubDate");
                 }
                 if ((flags & FEATURE_WRITE_GUID) != 0) {
@@ -132,4 +134,9 @@ public class Rss2Generator implements FeedGenerator {
 
         xml.endDocument();
     }
+
+    private static String formatRfc822Date(Date date) {
+        SimpleDateFormat format = new SimpleDateFormat("dd MMM yy HH:mm:ss Z", Locale.US);
+        return format.format(date);
+    }
 }

app/src/main/java/de/danoeh/antennapod/activity/OpmlImportActivity.java

@@ -26,14 +26,14 @@ import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.core.app.ActivityCompat;
 import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.core.export.opml.OpmlElement;
-import de.danoeh.antennapod.core.export.opml.OpmlReader;
 import de.danoeh.antennapod.core.preferences.ThemeSwitcher;
 
 import de.danoeh.antennapod.core.storage.DBTasks;
 import de.danoeh.antennapod.core.util.download.FeedUpdateManager;
 import de.danoeh.antennapod.databinding.OpmlSelectionBinding;
 import de.danoeh.antennapod.model.feed.Feed;
+import de.danoeh.antennapod.storage.importexport.OpmlElement;
+import de.danoeh.antennapod.storage.importexport.OpmlReader;
 import io.reactivex.Completable;
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;

app/src/main/java/de/danoeh/antennapod/asynctask/DocumentFileExportWorker.java

@@ -1,68 +0,0 @@
-package de.danoeh.antennapod.asynctask;
-
-import android.content.Context;
-import android.net.Uri;
-import androidx.annotation.NonNull;
-import androidx.documentfile.provider.DocumentFile;
-
-import java.io.IOException;
-import java.io.OutputStream;
-import java.io.OutputStreamWriter;
-import java.nio.charset.Charset;
-
-import de.danoeh.antennapod.core.export.ExportWriter;
-import de.danoeh.antennapod.core.storage.DBReader;
-import io.reactivex.Observable;
-
-/**
- * Writes an OPML file into the user selected export directory in the background.
- */
-public class DocumentFileExportWorker {
-
-    private final @NonNull ExportWriter exportWriter;
-    private @NonNull Context context;
-    private @NonNull Uri outputFileUri;
-
-    public DocumentFileExportWorker(@NonNull ExportWriter exportWriter, @NonNull Context context, @NonNull Uri outputFileUri) {
-        this.exportWriter = exportWriter;
-        this.context = context;
-        this.outputFileUri = outputFileUri;
-    }
-
-    public Observable<DocumentFile> exportObservable() {
-        DocumentFile output = DocumentFile.fromSingleUri(context, outputFileUri);
-        return Observable.create(subscriber -> {
-            OutputStream outputStream = null;
-            OutputStreamWriter writer = null;
-            try {
-                Uri uri = output.getUri();
-                outputStream = context.getContentResolver().openOutputStream(uri, "wt");
-                if (outputStream == null) {
-                    throw new IOException();
-                }
-                writer = new OutputStreamWriter(outputStream, Charset.forName("UTF-8"));
-                exportWriter.writeDocument(DBReader.getFeedList(), writer, context);
-                subscriber.onNext(output);
-            } catch (IOException e) {
-                subscriber.onError(e);
-            } finally {
-                if (writer != null) {
-                    try {
-                        writer.close();
-                    } catch (IOException e) {
-                        subscriber.onError(e);
-                    }
-                }
-                if (outputStream != null) {
-                    try {
-                        outputStream.close();
-                    } catch (IOException e) {
-                        subscriber.onError(e);
-                    }
-                }
-                subscriber.onComplete();
-            }
-        });
-    }
-
-}

app/src/main/java/de/danoeh/antennapod/asynctask/ExportWorker.java

@@ -1,68 +0,0 @@
-package de.danoeh.antennapod.asynctask;
-
-import android.content.Context;
-import androidx.annotation.NonNull;
-import android.util.Log;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.io.OutputStreamWriter;
-import java.nio.charset.Charset;
-
-import de.danoeh.antennapod.core.export.ExportWriter;
-import de.danoeh.antennapod.storage.preferences.UserPreferences;
-import de.danoeh.antennapod.core.storage.DBReader;
-import io.reactivex.Observable;
-
-/**
- * Writes an OPML file into the export directory in the background.
- */
-public class ExportWorker {
-
-    private static final String EXPORT_DIR = "export/";
-    private static final String TAG = "ExportWorker";
-    private static final String DEFAULT_OUTPUT_NAME = "antennapod-feeds";
-
-    private final @NonNull ExportWriter exportWriter;
-    private final @NonNull File output;
-    private final Context context;
-
-    public ExportWorker(@NonNull ExportWriter exportWriter, Context context) {
-        this(exportWriter, new File(UserPreferences.getDataFolder(EXPORT_DIR),
-                DEFAULT_OUTPUT_NAME + "." + exportWriter.fileExtension()), context);
-    }
-
-    private ExportWorker(@NonNull ExportWriter exportWriter, @NonNull File output, Context context) {
-        this.exportWriter = exportWriter;
-        this.output = output;
-        this.context = context;
-    }
-
-    public Observable<File> exportObservable() {
-        if (output.exists()) {
-            boolean success = output.delete();
-            Log.w(TAG, "Overwriting previously exported file: " + success);
-        }
-        return Observable.create(subscriber -> {
-            OutputStreamWriter writer = null;
-            try {
-                writer = new OutputStreamWriter(new FileOutputStream(output), Charset.forName("UTF-8"));
-                exportWriter.writeDocument(DBReader.getFeedList(), writer, context);
-                subscriber.onNext(output);
-            } catch (IOException e) {
-                subscriber.onError(e);
-            } finally {
-                if (writer != null) {
-                    try {
-                        writer.close();
-                    } catch (IOException e) {
-                        subscriber.onError(e);
-                    }
-                }
-                subscriber.onComplete();
-            }
-        });
-    }
-
-}

app/src/main/java/de/danoeh/antennapod/fragment/preferences/ImportExportPreferencesFragment.java

@@ -16,6 +16,7 @@ import androidx.activity.result.contract.ActivityResultContracts.GetContent;
 import androidx.activity.result.contract.ActivityResultContracts.StartActivityForResult;
 import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
+import androidx.documentfile.provider.DocumentFile;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import androidx.core.app.ShareCompat;
 import androidx.core.content.FileProvider;
@@ -25,13 +26,15 @@ import de.danoeh.antennapod.PodcastApp;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.OpmlImportActivity;
 import de.danoeh.antennapod.activity.PreferenceActivity;
-import de.danoeh.antennapod.asynctask.DocumentFileExportWorker;
+import de.danoeh.antennapod.core.storage.DBReader;
-import de.danoeh.antennapod.asynctask.ExportWorker;
+import de.danoeh.antennapod.model.feed.FeedItem;
-import de.danoeh.antennapod.core.export.ExportWriter;
+import de.danoeh.antennapod.model.feed.FeedItemFilter;
-import de.danoeh.antennapod.core.export.favorites.FavoritesWriter;
+import de.danoeh.antennapod.model.feed.SortOrder;
-import de.danoeh.antennapod.core.export.html.HtmlWriter;
+import de.danoeh.antennapod.storage.importexport.DatabaseExporter;
-import de.danoeh.antennapod.core.export.opml.OpmlWriter;
+import de.danoeh.antennapod.storage.importexport.FavoritesWriter;
-import de.danoeh.antennapod.core.storage.DatabaseExporter;
+import de.danoeh.antennapod.storage.importexport.HtmlWriter;
+import de.danoeh.antennapod.storage.importexport.OpmlWriter;
+import de.danoeh.antennapod.storage.preferences.UserPreferences;
 import io.reactivex.Completable;
 import io.reactivex.Observable;
 import io.reactivex.android.schedulers.AndroidSchedulers;
@@ -39,8 +42,14 @@ import io.reactivex.disposables.Disposable;
 import io.reactivex.schedulers.Schedulers;
 
 import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.nio.charset.Charset;
 import java.text.SimpleDateFormat;
 import java.util.Date;
+import java.util.List;
 import java.util.Locale;
 
 public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
@@ -57,18 +66,29 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
     private static final String CONTENT_TYPE_HTML = "text/html";
     private static final String DEFAULT_FAVORITES_OUTPUT_NAME = "antennapod-favorites-%s.html";
     private static final String DATABASE_EXPORT_FILENAME = "AntennaPodBackup-%s.db";
+
     private final ActivityResultLauncher<Intent> chooseOpmlExportPathLauncher =
-            registerForActivityResult(new StartActivityForResult(), this::chooseOpmlExportPathResult);
+            registerForActivityResult(new StartActivityForResult(),
+                    result -> exportToDocument(result, Export.OPML));
     private final ActivityResultLauncher<Intent> chooseHtmlExportPathLauncher =
-            registerForActivityResult(new StartActivityForResult(), this::chooseHtmlExportPathResult);
+            registerForActivityResult(new StartActivityForResult(),
+                    result -> exportToDocument(result, Export.HTML));
     private final ActivityResultLauncher<Intent> chooseFavoritesExportPathLauncher =
-            registerForActivityResult(new StartActivityForResult(), this::chooseFavoritesExportPathResult);
+            registerForActivityResult(new StartActivityForResult(),
+                    result -> exportToDocument(result, Export.FAVORITES));
     private final ActivityResultLauncher<Intent> restoreDatabaseLauncher =
             registerForActivityResult(new StartActivityForResult(), this::restoreDatabaseResult);
     private final ActivityResultLauncher<String> backupDatabaseLauncher =
             registerForActivityResult(new BackupDatabase(), this::backupDatabaseResult);
     private final ActivityResultLauncher<String> chooseOpmlImportPathLauncher =
-            registerForActivityResult(new GetContent(), this::chooseOpmlImportPathResult);
+            registerForActivityResult(new GetContent(), uri -> {
+                if (uri != null) {
+                    final Intent intent = new Intent(getContext(), OpmlImportActivity.class);
+                    intent.setData(uri);
+                    startActivity(intent);
+                }
+            });
+
     private Disposable disposable;
     private ProgressDialog progressDialog;
 
@@ -95,20 +115,16 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
         }
     }
 
-    private String dateStampFilename(String fname) {
-        return String.format(fname, new SimpleDateFormat("yyyy-MM-dd", Locale.US).format(new Date()));
-    }
-
     private void setupStorageScreen() {
         findPreference(PREF_OPML_EXPORT).setOnPreferenceClickListener(
                 preference -> {
-                    openExportPathPicker(Export.OPML, chooseOpmlExportPathLauncher, new OpmlWriter());
+                    openExportPathPicker(Export.OPML, chooseOpmlExportPathLauncher);
                     return true;
                 }
         );
         findPreference(PREF_HTML_EXPORT).setOnPreferenceClickListener(
                 preference -> {
-                    openExportPathPicker(Export.HTML, chooseHtmlExportPathLauncher, new HtmlWriter());
+                    openExportPathPicker(Export.HTML, chooseHtmlExportPathLauncher);
                     return true;
                 });
         findPreference(PREF_OPML_IMPORT).setOnPreferenceClickListener(
@@ -132,32 +148,13 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
                 });
         findPreference(PREF_FAVORITE_EXPORT).setOnPreferenceClickListener(
                 preference -> {
-                    openExportPathPicker(Export.FAVORITES, chooseFavoritesExportPathLauncher, new FavoritesWriter());
+                    openExportPathPicker(Export.FAVORITES, chooseFavoritesExportPathLauncher);
                     return true;
                 });
     }
 
-    private void exportWithWriter(ExportWriter exportWriter, Uri uri, Export exportType) {
+    private String dateStampFilename(String fname) {
-        Context context = getActivity();
+        return String.format(fname, new SimpleDateFormat("yyyy-MM-dd", Locale.US).format(new Date()));
-        progressDialog.show();
-        if (uri == null) {
-            Observable<File> observable = new ExportWorker(exportWriter, getContext()).exportObservable();
-            disposable = observable.subscribeOn(Schedulers.io())
-                    .observeOn(AndroidSchedulers.mainThread())
-                    .subscribe(output -> {
-                        Uri fileUri = FileProvider.getUriForFile(context.getApplicationContext(),
-                                context.getString(R.string.provider_authority), output);
-                        showExportSuccessSnackbar(fileUri, exportType.contentType);
-                    }, this::showExportErrorDialog, progressDialog::dismiss);
-        } else {
-            DocumentFileExportWorker worker = new DocumentFileExportWorker(exportWriter, context, uri);
-            disposable = worker.exportObservable()
-                    .subscribeOn(Schedulers.io())
-                    .observeOn(AndroidSchedulers.mainThread())
-                    .subscribe(output ->
-                            showExportSuccessSnackbar(output.getUri(), exportType.contentType),
-                            this::showExportErrorDialog, progressDialog::dismiss);
-        }
     }
 
     private void exportDatabase() {
@@ -211,30 +208,6 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
         alert.show();
     }
 
-    private void chooseOpmlExportPathResult(final ActivityResult result) {
-        if (result.getResultCode() != Activity.RESULT_OK || result.getData() == null) {
-            return;
-        }
-        final Uri uri = result.getData().getData();
-        exportWithWriter(new OpmlWriter(), uri, Export.OPML);
-    }
-
-    private void chooseHtmlExportPathResult(final ActivityResult result) {
-        if (result.getResultCode() != Activity.RESULT_OK || result.getData() == null) {
-            return;
-        }
-        final Uri uri = result.getData().getData();
-        exportWithWriter(new HtmlWriter(), uri, Export.HTML);
-    }
-
-    private void chooseFavoritesExportPathResult(final ActivityResult result) {
-        if (result.getResultCode() != Activity.RESULT_OK || result.getData() == null) {
-            return;
-        }
-        final Uri uri = result.getData().getData();
-        exportWithWriter(new FavoritesWriter(), uri, Export.FAVORITES);
-    }
-
     private void restoreDatabaseResult(final ActivityResult result) {
         if (result.getResultCode() != Activity.RESULT_OK || result.getData() == null) {
             return;
@@ -264,16 +237,7 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
                 }, this::showExportErrorDialog);
     }
 
-    private void chooseOpmlImportPathResult(final Uri uri) {
+    private void openExportPathPicker(Export exportType, ActivityResultLauncher<Intent> result) {
-        if (uri == null) {
-            return;
-        }
-        final Intent intent = new Intent(getContext(), OpmlImportActivity.class);
-        intent.setData(uri);
-        startActivity(intent);
-    }
-
-    private void openExportPathPicker(Export exportType, ActivityResultLauncher<Intent> result, ExportWriter writer) {
         String title = dateStampFilename(exportType.outputNameTemplate);
 
         Intent intentPickAction = new Intent(Intent.ACTION_CREATE_DOCUMENT)
@@ -292,7 +256,78 @@ public class ImportExportPreferencesFragment extends PreferenceFragmentCompat {
 
         // If we are using a SDK lower than API 21 or the implicit intent failed
         // fallback to the legacy export process
-        exportWithWriter(writer, null, exportType);
+        File output = new File(UserPreferences.getDataFolder("export/"), title);
+        exportToFile(exportType, output);
+    }
+
+    private void exportToFile(Export exportType, File output) {
+        progressDialog.show();
+        disposable = Observable.create(
+                subscriber -> {
+                    if (output.exists()) {
+                        boolean success = output.delete();
+                        Log.w(TAG, "Overwriting previously exported file: " + success);
+                    }
+                    try (FileOutputStream fileOutputStream = new FileOutputStream(output)) {
+                        writeToStream(fileOutputStream, exportType);
+                        subscriber.onNext(output);
+                    } catch (IOException e) {
+                        subscriber.onError(e);
+                    }
+                })
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(outputFile -> {
+                    progressDialog.dismiss();
+                    Uri fileUri = FileProvider.getUriForFile(getActivity().getApplicationContext(),
+                            getString(R.string.provider_authority), output);
+                    showExportSuccessSnackbar(fileUri, exportType.contentType);
+                }, this::showExportErrorDialog, progressDialog::dismiss);
+    }
+
+    private void exportToDocument(final ActivityResult result, Export exportType) {
+        if (result.getResultCode() != Activity.RESULT_OK || result.getData() == null) {
+            return;
+        }
+        progressDialog.show();
+        DocumentFile output = DocumentFile.fromSingleUri(getContext(), result.getData().getData());
+        disposable = Observable.create(
+                subscriber -> {
+                    try (OutputStream outputStream = getContext().getContentResolver()
+                            .openOutputStream(output.getUri(), "wt")) {
+                        writeToStream(outputStream, exportType);
+                        subscriber.onNext(output);
+                    } catch (IOException e) {
+                        subscriber.onError(e);
+                    }
+                })
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(ignore -> {
+                    progressDialog.dismiss();
+                    showExportSuccessSnackbar(output.getUri(), exportType.contentType);
+                }, this::showExportErrorDialog, progressDialog::dismiss);
+    }
+
+    private void writeToStream(OutputStream outputStream, Export type) throws IOException {
+        try (OutputStreamWriter writer = new OutputStreamWriter(outputStream, Charset.forName("UTF-8"))) {
+            switch (type) {
+                case HTML:
+                    HtmlWriter.writeDocument(DBReader.getFeedList(), writer, getContext());
+                    break;
+                case OPML:
+                    OpmlWriter.writeDocument(DBReader.getFeedList(), writer);
+                    break;
+                case FAVORITES:
+                    List<FeedItem> allFavorites = DBReader.getEpisodes(0, Integer.MAX_VALUE,
+                            new FeedItemFilter(FeedItemFilter.IS_FAVORITE), SortOrder.DATE_NEW_OLD);
+                    FavoritesWriter.writeDocument(allFavorites, writer, getContext());
+                    break;
+                default:
+                    showExportErrorDialog(new Exception("Invalid export type"));
+                    break;
+            }
+        }
     }
 
     private static class BackupDatabase extends ActivityResultContracts.CreateDocument {

core/build.gradle

@@ -35,6 +35,7 @@ dependencies {
     implementation project(':playback:base')
     implementation project(':playback:cast')
     implementation project(':storage:database')
+    implementation project(':storage:importexport')
     implementation project(':storage:preferences')
     implementation project(':ui:app-start-intent')
     implementation project(':ui:common')

core/src/main/java/de/danoeh/antennapod/core/backup/OpmlBackupAgent.java

@@ -10,6 +10,9 @@ import android.util.Log;
 
 import de.danoeh.antennapod.core.storage.DBTasks;
 import de.danoeh.antennapod.core.util.download.FeedUpdateManager;
+import de.danoeh.antennapod.storage.importexport.OpmlElement;
+import de.danoeh.antennapod.storage.importexport.OpmlReader;
+import de.danoeh.antennapod.storage.importexport.OpmlWriter;
 import org.apache.commons.io.IOUtils;
 import org.xmlpull.v1.XmlPullParserException;
 
@@ -31,9 +34,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 
-import de.danoeh.antennapod.core.export.opml.OpmlElement;
-import de.danoeh.antennapod.core.export.opml.OpmlReader;
-import de.danoeh.antennapod.core.export.opml.OpmlWriter;
 import de.danoeh.antennapod.model.feed.Feed;
 import de.danoeh.antennapod.core.storage.DBReader;
 
@@ -81,7 +81,7 @@ public class OpmlBackupAgent extends BackupAgentHelper {
 
             try {
                 // Write OPML
-                new OpmlWriter().writeDocument(DBReader.getFeedList(), writer, mContext);
+                OpmlWriter.writeDocument(DBReader.getFeedList(), writer);
 
                 // Compare checksum of new and old file to see if we need to perform a backup at all
                 if (digester != null) {

core/src/main/java/de/danoeh/antennapod/core/export/CommonSymbols.java

@@ -1,25 +0,0 @@
-/*
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package de.danoeh.antennapod.core.export;
-
-public class CommonSymbols {
-
-    public static final String HEAD = "head";
-    public static final String BODY = "body";
-    public static final String TITLE = "title";
-
-    public static final String XML_FEATURE_INDENT_OUTPUT = "http://xmlpull.org/v1/doc/features.html#indent-output";
-
-}

core/src/main/java/de/danoeh/antennapod/core/export/ExportWriter.java

@@ -1,31 +0,0 @@
-/*
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package de.danoeh.antennapod.core.export;
-
-import android.content.Context;
-import java.io.IOException;
-import java.io.Writer;
-import java.util.List;
-
-import de.danoeh.antennapod.model.feed.Feed;
-
-public interface ExportWriter {
-
-    void writeDocument(List<Feed> feeds, Writer writer, Context context)
-            throws IllegalArgumentException, IllegalStateException, IOException;
-
-    String fileExtension();
-
-}

core/src/main/java/de/danoeh/antennapod/core/util/DateFormatter.java

@@ -3,11 +3,9 @@ package de.danoeh.antennapod.core.util;
 import android.content.Context;
 
 import java.text.DateFormat;
-import java.text.SimpleDateFormat;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.GregorianCalendar;
-import java.util.Locale;
 
 /**
  * Formats dates.
@@ -17,11 +15,6 @@ public class DateFormatter {
 
     }
 
-    public static String formatRfc822Date(Date date) {
-        SimpleDateFormat format = new SimpleDateFormat("dd MMM yy HH:mm:ss Z", Locale.US);
-        return format.format(date);
-    }
-
     public static String formatAbbrev(final Context context, final Date date) {
         if (date == null) {
             return "";

settings.gradle

@@ -34,6 +34,7 @@ include ':playback:base'
 include ':playback:cast'
 
 include ':storage:database'
+include ':storage:importexport'
 include ':storage:preferences'
 
 include ':ui:app-start-intent'

storage/importexport/README.md

@@ -0,0 +1,3 @@
+# :storage:importexport
+
+Import/Export of the AntennaPod database.

storage/importexport/build.gradle

@@ -0,0 +1,21 @@
+plugins {
+    id("com.android.library")
+}
+apply from: "../../common.gradle"
+
+android {
+    namespace "de.danoeh.antennapod.storage.importexport"
+}
+
+dependencies {
+    implementation project(':storage:database')
+    implementation project(':storage:preferences')
+    implementation project(':ui:i18n')
+    implementation project(':model')
+
+    annotationProcessor "androidx.annotation:annotation:$annotationVersion"
+    implementation "commons-io:commons-io:$commonsioVersion"
+    implementation "io.reactivex.rxjava2:rxandroid:$rxAndroidVersion"
+    implementation "io.reactivex.rxjava2:rxjava:$rxJavaVersion"
+    implementation 'androidx.documentfile:documentfile:1.0.1'
+}

storage/importexport/src/main/assets/html-export-template.html

@@ -16,6 +16,7 @@
                 background-image: linear-gradient(180deg, #0f9cff, #0682ff);
                 text-align: center;
                 padding: 10px;
+                min-height: 100%;
             }
             h1 {
                 color: #fff;

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/DatabaseExporter.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.storage;
+package de.danoeh.antennapod.storage.importexport;
 
 import android.content.Context;
 import android.database.sqlite.SQLiteDatabase;
@@ -7,7 +7,6 @@ import android.net.Uri;
 import android.os.ParcelFileDescriptor;
 import android.text.format.Formatter;
 import android.util.Log;
-import de.danoeh.antennapod.core.R;
 import de.danoeh.antennapod.storage.database.PodDBAdapter;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/FavoritesWriter.java

@@ -1,9 +1,8 @@
-package de.danoeh.antennapod.core.export.favorites;
+package de.danoeh.antennapod.storage.importexport;
 
 import android.content.Context;
 import android.util.Log;
 
-import de.danoeh.antennapod.model.feed.FeedItemFilter;
 import org.apache.commons.io.IOUtils;
 
 import java.io.IOException;
@@ -14,21 +13,17 @@ import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
 
-import de.danoeh.antennapod.core.export.ExportWriter;
 import de.danoeh.antennapod.model.feed.Feed;
 import de.danoeh.antennapod.model.feed.FeedItem;
-import de.danoeh.antennapod.core.storage.DBReader;
-import de.danoeh.antennapod.model.feed.SortOrder;
 
 /** Writes saved favorites to file. */
-public class FavoritesWriter implements ExportWriter {
+public class FavoritesWriter {
     private static final String TAG = "FavoritesWriter";
     private static final String FAVORITE_TEMPLATE = "html-export-favorites-item-template.html";
     private static final String FEED_TEMPLATE = "html-export-feed-template.html";
     private static final String UTF_8 = "UTF-8";
 
-    @Override
+    public static void writeDocument(List<FeedItem> allFavorites, Writer writer, Context context)
-    public void writeDocument(List<Feed> feeds, Writer writer, Context context)
             throws IllegalArgumentException, IllegalStateException, IOException {
         Log.d(TAG, "Starting to write document");
 
@@ -43,8 +38,6 @@ public class FavoritesWriter implements ExportWriter {
         InputStream feedTemplateStream = context.getAssets().open(FEED_TEMPLATE);
         String feedTemplate = IOUtils.toString(feedTemplateStream, UTF_8);
 
-        List<FeedItem> allFavorites = DBReader.getEpisodes(0, Integer.MAX_VALUE,
-                new FeedItemFilter(FeedItemFilter.IS_FAVORITE), SortOrder.DATE_NEW_OLD);
         Map<Long, List<FeedItem>> favoriteByFeed = getFeedMap(allFavorites);
 
         writer.append(templateParts[0]);
@@ -72,7 +65,7 @@ public class FavoritesWriter implements ExportWriter {
      * @param favoritesList {@code List} of all favorite episodes.
      * @return A {@code Map} favorite episodes, keyed by feed ID.
      */
-    private Map<Long, List<FeedItem>> getFeedMap(List<FeedItem> favoritesList) {
+    private static Map<Long, List<FeedItem>> getFeedMap(List<FeedItem> favoritesList) {
         Map<Long, List<FeedItem>> feedMap = new TreeMap<>();
 
         for (FeedItem item : favoritesList) {
@@ -89,7 +82,7 @@ public class FavoritesWriter implements ExportWriter {
         return feedMap;
     }
 
-    private void writeFeed(Writer writer, Feed feed, String feedTemplate) throws IOException {
+    private static void writeFeed(Writer writer, Feed feed, String feedTemplate) throws IOException {
         String feedInfo = feedTemplate
                 .replace("{FEED_IMG}", feed.getImageUrl())
                 .replace("{FEED_TITLE}", feed.getTitle())
@@ -99,7 +92,7 @@ public class FavoritesWriter implements ExportWriter {
         writer.append(feedInfo);
     }
 
-    private void writeFavoriteItem(Writer writer, FeedItem item, String favoriteTemplate) throws IOException {
+    private static void writeFavoriteItem(Writer writer, FeedItem item, String favoriteTemplate) throws IOException {
         String favItem = favoriteTemplate.replace("{FAV_TITLE}", item.getTitle().trim());
         if (item.getLink() != null) {
             favItem = favItem.replace("{FAV_WEBSITE}", item.getLink());
@@ -114,9 +107,4 @@ public class FavoritesWriter implements ExportWriter {
 
         writer.append(favItem);
     }
-
-    @Override
-    public String fileExtension() {
-        return "html";
-    }
 }

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/HtmlWriter.java

@@ -1,8 +1,7 @@
-package de.danoeh.antennapod.core.export.html;
+package de.danoeh.antennapod.storage.importexport;
 
 import android.content.Context;
 import android.util.Log;
-import de.danoeh.antennapod.core.export.ExportWriter;
 import de.danoeh.antennapod.model.feed.Feed;
 import java.io.IOException;
 import java.io.InputStream;
@@ -11,15 +10,14 @@ import java.util.List;
 import org.apache.commons.io.IOUtils;
 
 /** Writes HTML documents. */
-public class HtmlWriter implements ExportWriter {
+public class HtmlWriter {
     private static final String TAG = "HtmlWriter";
 
     /**
      * Takes a list of feeds and a writer and writes those into an HTML
      * document.
      */
-    @Override
+    public static void writeDocument(List<Feed> feeds, Writer writer, Context context)
-    public void writeDocument(List<Feed> feeds, Writer writer, Context context)
             throws IllegalArgumentException, IllegalStateException, IOException {
         Log.d(TAG, "Starting to write document");
 
@@ -43,9 +41,4 @@ public class HtmlWriter implements ExportWriter {
         writer.append(templateParts[1]);
         Log.d(TAG, "Finished writing document");
     }
-
-    public String fileExtension() {
-        return "html";
-    }
-
 }

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/OpmlElement.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.export.opml;
+package de.danoeh.antennapod.storage.importexport;
 
 /**
  * Represents a single feed in an OPML file.

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/OpmlReader.java

@@ -1,7 +1,9 @@
-package de.danoeh.antennapod.core.export.opml;
+package de.danoeh.antennapod.storage.importexport;
 
+import android.text.TextUtils;
 import android.util.Log;
 
+import de.danoeh.antennapod.storage.preferences.BuildConfig;
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
 import org.xmlpull.v1.XmlPullParserFactory;
@@ -10,8 +12,6 @@ import java.io.IOException;
 import java.io.Reader;
 import java.util.ArrayList;
 
-import de.danoeh.antennapod.core.BuildConfig;
-
 /**
  * Reads OPML documents.
  */
@@ -53,7 +53,7 @@ public class OpmlReader {
                         OpmlElement element = new OpmlElement();
 
                         final String title = xpp.getAttributeValue(null, OpmlSymbols.TITLE);
-                        if (title != null) {
+                        if (!TextUtils.isEmpty(title)) {
                             Log.i(TAG, "Using title: " + title);
                             element.setText(title);
                         } else {
@@ -63,8 +63,8 @@ public class OpmlReader {
                         element.setXmlUrl(xpp.getAttributeValue(null, OpmlSymbols.XMLURL));
                         element.setHtmlUrl(xpp.getAttributeValue(null, OpmlSymbols.HTMLURL));
                         element.setType(xpp.getAttributeValue(null, OpmlSymbols.TYPE));
-                        if (element.getXmlUrl() != null) {
+                        if (!TextUtils.isEmpty(element.getXmlUrl())) {
-                            if (element.getText() == null) {
+                            if (TextUtils.isEmpty(element.getText())) {
                                 Log.i(TAG, "Opml element has no text attribute.");
                                 element.setText(element.getXmlUrl());
                             }

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/OpmlSymbols.java

@@ -1,12 +1,14 @@
-package de.danoeh.antennapod.core.export.opml;
+package de.danoeh.antennapod.storage.importexport;
-
-import de.danoeh.antennapod.core.export.CommonSymbols;
 
 /**
  * Contains symbols for reading and writing OPML documents.
  */
-final class OpmlSymbols extends CommonSymbols {
+final class OpmlSymbols {
+    public static final String XML_FEATURE_INDENT_OUTPUT = "http://xmlpull.org/v1/doc/features.html#indent-output";
 
+    public static final String HEAD = "head";
+    public static final String BODY = "body";
+    public static final String TITLE = "title";
     public static final String OPML = "opml";
     static final String OUTLINE = "outline";
     static final String TEXT = "text";
@@ -19,5 +21,4 @@ final class OpmlSymbols extends CommonSymbols {
     private OpmlSymbols() {
 
     }
-
 }

storage/importexport/src/main/java/de/danoeh/antennapod/storage/importexport/OpmlWriter.java

@@ -1,22 +1,21 @@
-package de.danoeh.antennapod.core.export.opml;
+package de.danoeh.antennapod.storage.importexport;
 
-import android.content.Context;
 import android.util.Log;
 import android.util.Xml;
 
-import de.danoeh.antennapod.core.util.DateFormatter;
 import org.xmlpull.v1.XmlSerializer;
 
 import java.io.IOException;
 import java.io.Writer;
+import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.List;
+import java.util.Locale;
 
-import de.danoeh.antennapod.core.export.ExportWriter;
 import de.danoeh.antennapod.model.feed.Feed;
 
 /** Writes OPML documents. */
-public class OpmlWriter implements ExportWriter {
+public class OpmlWriter {
 
     private static final String TAG = "OpmlWriter";
     private static final String ENCODING = "UTF-8";
@@ -27,8 +26,7 @@ public class OpmlWriter implements ExportWriter {
      * Takes a list of feeds and a writer and writes those into an OPML
      * document.
      */
-    @Override
+    public static void writeDocument(List<Feed> feeds, Writer writer)
-    public void writeDocument(List<Feed> feeds, Writer writer, Context context)
             throws IllegalArgumentException, IllegalStateException, IOException {
         Log.d(TAG, "Starting to write document");
         XmlSerializer xs = Xml.newSerializer();
@@ -44,7 +42,7 @@ public class OpmlWriter implements ExportWriter {
         xs.text(OPML_TITLE);
         xs.endTag(null, OpmlSymbols.TITLE);
         xs.startTag(null, OpmlSymbols.DATE_CREATED);
-        xs.text(DateFormatter.formatRfc822Date(new Date()));
+        xs.text(formatRfc822Date(new Date()));
         xs.endTag(null, OpmlSymbols.DATE_CREATED);
         xs.endTag(null, OpmlSymbols.HEAD);
 
@@ -68,8 +66,8 @@ public class OpmlWriter implements ExportWriter {
         Log.d(TAG, "Finished writing document");
     }
 
-    public String fileExtension() {
+    private static String formatRfc822Date(Date date) {
-        return "opml";
+        SimpleDateFormat format = new SimpleDateFormat("dd MMM yy HH:mm:ss Z", Locale.US);
+        return format.format(date);
     }
-
 }