Fixed: Improved database backup journal handling

src/NzbDrone.Core/Backup/BackupService.cs

@@ -1,6 +1,7 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Data;
+using System.Data.SQLite;
 using System.IO;
 using System.Linq;
 using System.Text.RegularExpressions;
@@ -25,6 +26,7 @@ namespace NzbDrone.Core.Backup
     public class BackupService : IBackupService, IExecute<BackupCommand>
     {
         private readonly IMainDatabase _maindDb;
+        private readonly IMakeDatabaseBackup _makeDatabaseBackup;
         private readonly IDiskTransferService _diskTransferService;
         private readonly IDiskProvider _diskProvider;
         private readonly IAppFolderInfo _appFolderInfo;
@@ -36,6 +38,7 @@ namespace NzbDrone.Core.Backup
         private static readonly Regex BackupFileRegex = new Regex(@"nzbdrone_backup_[._0-9]+\.zip", RegexOptions.Compiled | RegexOptions.IgnoreCase);
 
         public BackupService(IMainDatabase maindDb,
+                             IMakeDatabaseBackup makeDatabaseBackup,
                              IDiskTransferService diskTransferService,
                              IDiskProvider diskProvider,
                              IAppFolderInfo appFolderInfo,
@@ -43,6 +46,7 @@ namespace NzbDrone.Core.Backup
                              Logger logger)
         {
             _maindDb = maindDb;
+            _makeDatabaseBackup = makeDatabaseBackup;
             _diskTransferService = diskTransferService;
             _diskProvider = diskProvider;
             _appFolderInfo = appFolderInfo;
@@ -111,17 +115,7 @@ namespace NzbDrone.Core.Backup
         {
             _logger.ProgressDebug("Backing up database");
 
-            using (var unitOfWork = new UnitOfWork(() => _maindDb.GetDataMapper()))
+            _makeDatabaseBackup.BackupDatabase(_maindDb, _backupTempFolder);
-            {
-                unitOfWork.BeginTransaction(IsolationLevel.Serializable);
-
-                var databaseFile = _appFolderInfo.GetDatabase();
-                var tempDatabaseFile = Path.Combine(_backupTempFolder, Path.GetFileName(databaseFile));
-
-                _diskTransferService.TransferFile(databaseFile, tempDatabaseFile, TransferMode.Copy);
-
-                unitOfWork.Commit();
-            }
         }
 
         private void BackupConfigFile()

src/NzbDrone.Core/Backup/MakeDatabaseBackup.cs

@@ -0,0 +1,64 @@
+using System;
+using System.Collections.Generic;
+using System.Data.SQLite;
+using System.IO;
+using System.Linq;
+using System.Text;
+using NLog;
+using NzbDrone.Core.Datastore;
+using System.Data;
+
+namespace NzbDrone.Core.Backup
+{
+    public interface IMakeDatabaseBackup
+    {
+        void BackupDatabase(IDatabase database, string targetDirectory);
+    }
+
+    public class MakeDatabaseBackup : IMakeDatabaseBackup
+    {
+        private readonly Logger _logger;
+
+        public MakeDatabaseBackup(Logger logger)
+        {
+            _logger = logger;
+        }
+
+        public void BackupDatabase(IDatabase database, string targetDirectory)
+        {
+            var sourceConnectionString = database.GetDataMapper().ConnectionString;
+            var backupConnectionStringBuilder = new SQLiteConnectionStringBuilder(sourceConnectionString);
+
+            backupConnectionStringBuilder.DataSource = Path.Combine(targetDirectory, Path.GetFileName(backupConnectionStringBuilder.DataSource));
+
+            using (var sourceConnection = (SQLiteConnection)SQLiteFactory.Instance.CreateConnection())
+            using (var backupConnection = (SQLiteConnection)SQLiteFactory.Instance.CreateConnection())
+            {
+                sourceConnection.ConnectionString = sourceConnectionString;
+                backupConnection.ConnectionString = backupConnectionStringBuilder.ToString();
+
+                sourceConnection.Open();
+                backupConnection.Open();
+
+                sourceConnection.BackupDatabase(backupConnection, "main", "main", -1, null, 500);
+
+                // Make sure there are no lingering connections so the wal gets truncated.
+                SQLiteConnection.ClearAllPools();
+            }
+
+            var backupWalPath = backupConnectionStringBuilder.DataSource + "-wal";
+            if (backupConnectionStringBuilder.JournalMode == SQLiteJournalModeEnum.Wal && !File.Exists(backupWalPath))
+            {
+                // Make sure the wal gets created in the backup so users are less likely to make an error during restore.
+                File.WriteAllBytes(backupWalPath, new byte[0]);
+            }
+
+            var backupJournalPath = backupConnectionStringBuilder.DataSource + "-journal";
+            if (backupConnectionStringBuilder.JournalMode != SQLiteJournalModeEnum.Wal && !File.Exists(backupJournalPath))
+            {
+                // Make sure the journal gets created in the backup so users are less likely to make an error during restore.
+                File.WriteAllBytes(backupJournalPath, new byte[0]);
+            }
+        }
+    }
+}

src/NzbDrone.Core/Datastore/Database.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using Marr.Data;
 using NLog;
 using NzbDrone.Common.Instrumentation;
@@ -25,7 +25,6 @@ namespace NzbDrone.Core.Datastore
             _datamapperFactory = datamapperFactory;
         }
 
-
         public IDataMapper GetDataMapper()
         {
             return _datamapperFactory();

src/NzbDrone.Core/NzbDrone.Core.csproj

@@ -127,6 +127,7 @@
     <Compile Include="Backup\Backup.cs" />
     <Compile Include="Backup\BackupCommand.cs" />
     <Compile Include="Backup\BackupService.cs" />
+    <Compile Include="Backup\MakeDatabaseBackup.cs" />
     <Compile Include="Blacklisting\Blacklist.cs" />
     <Compile Include="Blacklisting\BlacklistRepository.cs" />
     <Compile Include="Blacklisting\BlacklistService.cs" />