Save app details to temp table, then flush after update verified.

F-Droid/AndroidManifest.xml

@@ -88,6 +88,11 @@
             android:name="org.fdroid.fdroid.data.TempApkProvider"
             android:exported="false"/>
 
+        <provider
+            android:authorities="org.fdroid.fdroid.data.TempAppProvider"
+            android:name="org.fdroid.fdroid.data.TempAppProvider"
+            android:exported="false"/>
+
         <provider
             android:authorities="org.fdroid.fdroid.data.InstalledAppProvider"
             android:name="org.fdroid.fdroid.data.InstalledAppProvider"

F-Droid/src/org/fdroid/fdroid/RepoUpdater.java

@@ -18,6 +18,7 @@ import org.fdroid.fdroid.data.AppProvider;
 import org.fdroid.fdroid.data.Repo;
 import org.fdroid.fdroid.data.RepoProvider;
 import org.fdroid.fdroid.data.TempApkProvider;
+import org.fdroid.fdroid.data.TempAppProvider;
 import org.fdroid.fdroid.net.Downloader;
 import org.fdroid.fdroid.net.DownloaderFactory;
 import org.xml.sax.InputSource;
@@ -203,11 +204,13 @@ public class RepoUpdater {
     }
 
     private void flushBufferToDb() throws UpdateException {
-        Log.d(TAG, "Flushing details of " + MAX_APP_BUFFER + " and their packages to the database.");
+        if (apksToSave.size() > 0 || appsToSave.size() > 0) {
-        flushAppsToDbInBatch();
+            Log.d(TAG, "Flushing details of up to " + MAX_APP_BUFFER + " apps and their packages to the database.");
-        flushApksToDbInBatch();
+            flushAppsToDbInBatch();
-        apksToSave.clear();
+            flushApksToDbInBatch();
-        appsToSave.clear();
+            apksToSave.clear();
+            appsToSave.clear();
+        }
     }
 
     private void flushApksToDbInBatch() throws UpdateException {
@@ -236,7 +239,7 @@ public class RepoUpdater {
         ArrayList<ContentProviderOperation> appOperations = insertOrUpdateApps(appsToSave);
 
         try {
-            context.getContentResolver().applyBatch(AppProvider.getAuthority(), appOperations);
+            context.getContentResolver().applyBatch(TempAppProvider.getAuthority(), appOperations);
         } catch (RemoteException|OperationApplicationException e) {
             Log.e(TAG, "Error updating apps", e);
             throw new UpdateException(repo, "Error updating apps: " + e.getMessage(), e);
@@ -290,7 +293,7 @@ public class RepoUpdater {
      * <strong>Does not do any checks to see if the app already exists or not.</strong>
      */
     private ContentProviderOperation updateExistingApp(App app) {
-        Uri uri = AppProvider.getContentUri(app);
+        Uri uri = TempAppProvider.getAppUri(app);
         ContentValues values = app.toContentValues();
         for (final String toIgnore : APP_FIELDS_TO_IGNORE) {
             if (values.containsKey(toIgnore)) {
@@ -306,7 +309,7 @@ public class RepoUpdater {
      */
     private ContentProviderOperation insertNewApp(App app) {
         ContentValues values = app.toContentValues();
-        Uri uri = AppProvider.getContentUri();
+        Uri uri = TempAppProvider.getContentUri();
         return ContentProviderOperation.newInsert(uri).withValues(values).build();
     }
 
@@ -415,6 +418,7 @@ public class RepoUpdater {
             // the index was signed with until we've finished reading it - and we don't
             // want to put stuff in the real database until we are sure it is from a
             // trusted source.
+            TempAppProvider.Helper.init(context);
             TempApkProvider.Helper.init(context);
 
             // Due to a bug in Android 5.0 Lollipop, the inclusion of spongycastle causes
@@ -433,12 +437,17 @@ public class RepoUpdater {
             final RepoXMLHandler repoXMLHandler = new RepoXMLHandler(repo, createIndexReceiver());
             reader.setContentHandler(repoXMLHandler);
             reader.parse(new InputSource(indexInputStream));
+
+            flushBufferToDb();
+
             signingCertFromJar = getSigningCertFromJar(indexEntry);
 
             // JarEntry can only read certificates after the file represented by that JarEntry
             // has been read completely, so verification cannot run until now...
             assertSigningCertFromXmlCorrect();
 
+            Log.i(TAG, "Repo signature verified, saving app metadata to database.");
+            TempAppProvider.Helper.commit(context);
             TempApkProvider.Helper.commit(context);
             RepoProvider.Helper.update(context, repo, repoDetailsToSave);
 

F-Droid/src/org/fdroid/fdroid/data/TempApkProvider.java

@@ -31,14 +31,12 @@ public class TempApkProvider extends ApkProvider {
 
     private static final int CODE_INIT = 10000;
     private static final int CODE_COMMIT = CODE_INIT + 1;
-    private static final int CODE_ROLLBACK = CODE_INIT + 2;
 
     private static final UriMatcher matcher = new UriMatcher(-1);
 
     static {
         matcher.addURI(getAuthority(), PATH_INIT, CODE_INIT);
         matcher.addURI(getAuthority(), PATH_COMMIT, CODE_COMMIT);
-        matcher.addURI(getAuthority(), PATH_ROLLBACK, CODE_ROLLBACK);
         matcher.addURI(getAuthority(), PATH_APK + "/#/*", CODE_SINGLE);
         matcher.addURI(getAuthority(), PATH_REPO_APK + "/#/*", CODE_REPO_APK);
     }
@@ -94,14 +92,6 @@ public class TempApkProvider extends ApkProvider {
             context.getContentResolver().insert(uri, new ContentValues());
         }
 
-        /**
-         * Not sure that this is strictly necessary, but this will remove the temp table.
-         */
-        public static void rollback(Context context) {
-            Uri uri = Uri.withAppendedPath(getContentUri(), PATH_ROLLBACK);
-            context.getContentResolver().insert(uri, new ContentValues());
-        }
-
     }
 
     @Override
@@ -114,16 +104,13 @@ public class TempApkProvider extends ApkProvider {
         } else if (code == CODE_COMMIT) {
             commitTable();
             return null;
-        } else if (code == CODE_ROLLBACK) {
-            removeTable();
-            return null;
         } else {
             return super.insert(uri, values);
         }
     }
 
     private void initTable() {
-        removeTable();
+        write().execSQL("DROP TABLE IF EXISTS " + getTableName());
         write().execSQL("CREATE TEMPORARY TABLE " + getTableName() + " AS SELECT * FROM " + DBHelper.TABLE_APK);
     }
 

F-Droid/src/org/fdroid/fdroid/data/TempAppProvider.java

@@ -0,0 +1,103 @@
+package org.fdroid.fdroid.data;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.UriMatcher;
+import android.net.Uri;
+import android.util.Log;
+
+import java.util.List;
+
+/**
+ * This class does all of its operations in a temporary sqlite table.
+ */
+public class TempAppProvider extends AppProvider {
+
+    private static final String TAG = "TempAppProvider";
+
+    private static final String PROVIDER_NAME = "TempAppProvider";
+
+    private static final String PATH_INIT = "init";
+    private static final String PATH_COMMIT = "commit";
+    private static final String PATH_ROLLBACK = "rollback";
+
+    private static final int CODE_INIT = 10000;
+    private static final int CODE_COMMIT = CODE_INIT + 1;
+
+    private static final UriMatcher matcher = new UriMatcher(-1);
+
+    static {
+        matcher.addURI(getAuthority(), PATH_INIT, CODE_INIT);
+        matcher.addURI(getAuthority(), PATH_COMMIT, CODE_COMMIT);
+        matcher.addURI(getAuthority(), "*", CODE_SINGLE);
+    }
+
+    @Override
+    protected String getTableName() {
+        return "temp_" + super.getTableName();
+    }
+
+    public static String getAuthority() {
+        return AUTHORITY + "." + PROVIDER_NAME;
+    }
+
+    public static Uri getContentUri() {
+        return Uri.parse("content://" + getAuthority());
+    }
+
+    public static Uri getAppUri(App app) {
+        return Uri.withAppendedPath(getContentUri(), app.id);
+    }
+
+    public static class Helper {
+
+        /**
+         * Deletes the old temporary table (if it exists). Then creates a new temporary apk provider
+         * table and populates it with all the data from the real apk provider table.
+         */
+        public static void init(Context context) {
+            Uri uri = Uri.withAppendedPath(getContentUri(), PATH_INIT);
+            context.getContentResolver().insert(uri, new ContentValues());
+        }
+
+        /**
+         * Saves data from the temp table to the apk table, by removing _EVERYTHING_ from the real
+         * apk table and inserting all of the records from here. The temporary table is then removed.
+         */
+        public static void commit(Context context) {
+            Uri uri = Uri.withAppendedPath(getContentUri(), PATH_COMMIT);
+            context.getContentResolver().insert(uri, new ContentValues());
+        }
+
+    }
+
+    @Override
+    public Uri insert(Uri uri, ContentValues values) {
+        int code = matcher.match(uri);
+
+        if (code == CODE_INIT) {
+            initTable();
+            return null;
+        } else if (code == CODE_COMMIT) {
+            commitTable();
+            return null;
+        } else {
+            return super.insert(uri, values);
+        }
+    }
+
+    private void initTable() {
+        write().execSQL("DROP TABLE IF EXISTS " + getTableName());
+        write().execSQL("CREATE TEMPORARY TABLE " + getTableName() + " AS SELECT * FROM " + DBHelper.TABLE_APP);
+    }
+
+    private void commitTable() {
+        Log.d(TAG, "Deleting all apks from " + DBHelper.TABLE_APP + " so they can be copied from " + getTableName());
+        write().execSQL("DELETE FROM " + DBHelper.TABLE_APP);
+        write().execSQL("INSERT INTO " + DBHelper.TABLE_APP + " SELECT * FROM " + getTableName());
+    }
+
+    private void removeTable() {
+
+    }
+}