Rework database loading/migration

Application/Data/Database.cs

@@ -1,218 +1,25 @@
-using FeedCenter.Properties;
-using Serilog;
-using System;
-using System.Collections.Generic;
-using System.Data.SqlServerCe;
-using System.IO;
-using System.Linq;
+using System.IO;
 
 namespace FeedCenter.Data
 {
     public static class Database
     {
-        #region Static database settings
+        public static string DatabaseFile { get; set; }
+        public static string DatabasePath { get; set; }
 
-        public static string DatabaseFile;
-        public static string DatabasePath;
+        public static FeedCenterEntities Entities { get; set; }
 
-        #endregion
+        public static bool Exists => File.Exists(DatabaseFile);
 
-        #region File version
-
-        public static FeedCenterEntities Entities;
-
-        private enum SqlServerCeFileVersion
-        {
-            Unknown,
-            Version20,
-            Version30,
-            Version35,
-            Version40,
-        }
+        public static bool Loaded { get; set; }
 
         public static void Load()
         {
+            if (Loaded) return;
+
             Entities = new FeedCenterEntities();
-        }
 
-        private static SqlServerCeFileVersion GetFileVersion(string databasePath)
-        {
-            // Create a mapping of version numbers to the version enumeration
-            var versionMapping = new Dictionary<int, SqlServerCeFileVersion>
-                    {
-                        { 0x73616261, SqlServerCeFileVersion.Version20 },
-                        { 0x002dd714, SqlServerCeFileVersion.Version30 },
-                        { 0x00357b9d, SqlServerCeFileVersion.Version35 },
-                        { 0x003d0900, SqlServerCeFileVersion.Version40 }
-                    };
-
-            int signature;
-
-            try
-            {
-                // Open the database file
-                using var stream = new FileStream(databasePath, FileMode.Open, FileAccess.Read);
-                // Read the file using the binary reader
-                var reader = new BinaryReader(stream);
-
-                // Seek to the version signature
-                stream.Seek(16, SeekOrigin.Begin);
-
-                // Read the version signature
-                signature = reader.ReadInt32();
-            }
-            catch (Exception exception)
-            {
-                Log.Logger.Error(exception, "Exception");
-
-                throw;
-            }
-
-            // If we know about the version number then return the right enumeration - otherwise unknown
-            return versionMapping.ContainsKey(signature) ? versionMapping[signature] : SqlServerCeFileVersion.Unknown;
-        }
-
-        #endregion
-
-        public static bool DatabaseExists => File.Exists(DatabaseFile);
-
-        public static void CreateDatabase()
-        {
-            Log.Logger.Information("Creating database engine");
-
-            // Create the database engine
-            using var engine = new SqlCeEngine($"Data Source={DatabaseFile}");
-            Log.Logger.Information("Creating database");
-
-            // Create the database itself
-            engine.CreateDatabase();
-
-            Log.Logger.Information("Running database script");
-
-            // Run the creation script                
-            ExecuteScript(Resources.CreateDatabase);
-        }
-
-        private static int GetVersion(SqlCeConnection connection)
-        {
-            string versionString;
-
-            try
-            {
-                // Check the database version table
-                using var command = new SqlCeCommand("SELECT Value FROM DatabaseVersion", connection);
-                versionString = command.ExecuteScalar().ToString();
-            }
-            catch (SqlCeException)
-            {
-                // Check the setting table for the version
-                using var command = new SqlCeCommand("SELECT Value FROM Setting WHERE Name = 'DatabaseVersion'", connection);
-                versionString = command.ExecuteScalar().ToString();
-            }
-
-            if (string.IsNullOrEmpty(versionString))
-                versionString = "0";
-
-            Log.Logger.Information("Database version: {0}", versionString);
-
-            return int.Parse(versionString);
-        }
-
-        public static void UpdateDatabase()
-        {
-            Log.Logger.Information("Getting database file version");
-
-            // Get the database file version
-            var fileVersion = GetFileVersion(DatabaseFile);
-
-            Log.Logger.Information("Database file version: {0}", fileVersion);
-
-            // See if we need to upgrade the database file version
-            if (fileVersion != SqlServerCeFileVersion.Version40)
-            {
-                Log.Logger.Information("Creating database engine");
-
-                // Create the database engine
-                using var engine = new SqlCeEngine($"Data Source={DatabaseFile}");
-                Log.Logger.Information("Upgrading database");
-
-                // Upgrade the database (if needed)
-                engine.Upgrade();
-            }
-
-            Log.Logger.Information("Getting database version");
-
-            // Create a database connection
-            using var connection = new SqlCeConnection($"Data Source={DatabaseFile}");
-            // Open the connection
-            connection.Open();
-
-            // Get the database version
-            var databaseVersion = GetVersion(connection);
-
-            // Create a dictionary of database upgrade scripts and their version numbers
-            var scriptList = new Dictionary<int, string>();
-
-            // Loop over the properties of the resource object looking for update scripts
-            foreach (var property in typeof(Resources).GetProperties().Where(property => property.Name.StartsWith("DatabaseUpdate")))
-            {
-                // Get the name of the property
-                var propertyName = property.Name;
-
-                // Extract the version from the name
-                var version = int.Parse(propertyName.Substring(propertyName.IndexOf("_", StringComparison.Ordinal) + 1));
-
-                // Add to the script list
-                scriptList[version] = propertyName;
-            }
-
-            // Loop over the scripts ordered by version
-            foreach (var pair in scriptList.OrderBy(pair => pair.Key))
-            {
-                // If the database version is less than or equal to the script version the script needs to run
-                if (databaseVersion <= pair.Key)
-                {
-                    // Get the script text
-                    var scriptText = Resources.ResourceManager.GetString(pair.Value);
-
-                    // Run the script
-                    ExecuteScript(scriptText);
-                }
-            }
-        }
-
-        public static void MaintainDatabase()
-        {
-            Log.Logger.Information("Creating database engine");
-
-            // Create the database engine
-            using var engine = new SqlCeEngine($"Data Source={DatabaseFile}");
-            Log.Logger.Information("Shrinking database");
-
-            // Compact the database
-            engine.Shrink();
-        }
-
-        private static void ExecuteScript(string scriptText)
-        {
-            // Create a database connection
-            using var connection = new SqlCeConnection($"Data Source={DatabaseFile}");
-            // Open the connection
-            connection.Open();
-
-            // Setup the delimiters
-            var delimiters = new[] { "\r\nGO\r\n" };
-
-            // Split the script at the delimiters
-            var statements = scriptText.Split(delimiters, StringSplitOptions.RemoveEmptyEntries);
-
-            // Loop over each statement in the script
-            foreach (var statement in statements)
-            {
-                // Execute the statement
-                using var command = new SqlCeCommand(statement, connection);
-                command.ExecuteNonQuery();
-            }
+            Loaded = true;
         }
     }
-}
+}

Application/Data/Extensions.cs

@@ -1,13 +0,0 @@
-using System.Data.SqlTypes;
-
-namespace FeedCenter.Data
-{
-    public static class Extensions
-    {
-        #region SqlDateTime
-
-        public static SqlDateTime SqlDateTimeZero = new SqlDateTime(0, 0);
-
-        #endregion
-    }
-}

Application/Data/LegacyDatabase.cs

@@ -0,0 +1,234 @@
+using Dapper;
+using FeedCenter.Options;
+using FeedCenter.Properties;
+using Realms;
+using Serilog;
+using System;
+using System.Collections.Generic;
+using System.Data.SqlServerCe;
+using System.IO;
+using System.Linq;
+
+namespace FeedCenter.Data;
+
+public static class LegacyDatabase
+{
+    public static string DatabaseFile { get; set; }
+    public static string DatabasePath { get; set; }
+
+    private enum SqlServerCeFileVersion
+    {
+        Unknown,
+        Version20,
+        Version30,
+        Version35,
+        Version40,
+    }
+
+    private static SqlServerCeFileVersion GetFileVersion(string databasePath)
+    {
+        // Create a mapping of version numbers to the version enumeration
+        var versionMapping = new Dictionary<int, SqlServerCeFileVersion>
+        {
+            { 0x73616261, SqlServerCeFileVersion.Version20 },
+            { 0x002dd714, SqlServerCeFileVersion.Version30 },
+            { 0x00357b9d, SqlServerCeFileVersion.Version35 },
+            { 0x003d0900, SqlServerCeFileVersion.Version40 }
+        };
+
+        int signature;
+
+        try
+        {
+            // Open the database file
+            using var stream = new FileStream(databasePath, FileMode.Open, FileAccess.Read);
+            // Read the file using the binary reader
+            var reader = new BinaryReader(stream);
+
+            // Seek to the version signature
+            stream.Seek(16, SeekOrigin.Begin);
+
+            // Read the version signature
+            signature = reader.ReadInt32();
+        }
+        catch (Exception exception)
+        {
+            Log.Logger.Error(exception, "Exception");
+
+            throw;
+        }
+
+        // If we know about the version number then return the right enumeration - otherwise unknown
+        return versionMapping.TryGetValue(signature, out var value) ? value : SqlServerCeFileVersion.Unknown;
+    }
+
+    public static bool Exists => File.Exists(DatabaseFile);
+
+    private static int GetVersion(SqlCeConnection connection)
+    {
+        string versionString;
+
+        try
+        {
+            // Check the database version table
+            using var command = new SqlCeCommand("SELECT Value FROM DatabaseVersion", connection);
+            versionString = command.ExecuteScalar().ToString();
+        }
+        catch (SqlCeException)
+        {
+            // Check the setting table for the version
+            using var command = new SqlCeCommand("SELECT Value FROM Setting WHERE Name = 'DatabaseVersion'", connection);
+            versionString = command.ExecuteScalar().ToString();
+        }
+
+        if (string.IsNullOrEmpty(versionString))
+            versionString = "0";
+
+        Log.Logger.Information("Database version: {0}", versionString);
+
+        return int.Parse(versionString);
+    }
+
+    public static void UpdateDatabase()
+    {
+        Log.Logger.Information("Getting database file version");
+
+        // Get the database file version
+        var fileVersion = GetFileVersion(DatabaseFile);
+
+        Log.Logger.Information("Database file version: {0}", fileVersion);
+
+        // See if we need to upgrade the database file version
+        if (fileVersion != SqlServerCeFileVersion.Version40)
+        {
+            Log.Logger.Information("Creating database engine");
+
+            // Create the database engine
+            using var engine = new SqlCeEngine($"Data Source={DatabaseFile}");
+            Log.Logger.Information("Upgrading database");
+
+            // Upgrade the database (if needed)
+            engine.Upgrade();
+        }
+
+        Log.Logger.Information("Getting database version");
+
+        // Create a database connection
+        using var connection = new SqlCeConnection($"Data Source={DatabaseFile}");
+        // Open the connection
+        connection.Open();
+
+        // Get the database version
+        var databaseVersion = GetVersion(connection);
+
+        // Create a dictionary of database upgrade scripts and their version numbers
+        var scriptList = new Dictionary<int, string>();
+
+        // Loop over the properties of the resource object looking for update scripts
+        foreach (var property in typeof(Resources).GetProperties().Where(property => property.Name.StartsWith("DatabaseUpdate")))
+        {
+            // Get the name of the property
+            var propertyName = property.Name;
+
+            // Extract the version from the name
+            var version = int.Parse(propertyName[(propertyName.IndexOf("_", StringComparison.Ordinal) + 1)..]);
+
+            // Add to the script list
+            scriptList[version] = propertyName;
+        }
+
+        // Loop over the scripts ordered by version
+        foreach (var pair in scriptList.OrderBy(pair => pair.Key))
+        {
+            // If the database version is beyond this script then we can skip it
+            if (databaseVersion > pair.Key) continue;
+
+            // Get the script text
+            var scriptText = Resources.ResourceManager.GetString(pair.Value);
+
+            // Run the script
+            ExecuteScript(scriptText);
+        }
+    }
+
+    public static void MaintainDatabase()
+    {
+        Log.Logger.Information("Creating database engine");
+
+        // Create the database engine
+        using var engine = new SqlCeEngine($"Data Source={DatabaseFile}");
+        Log.Logger.Information("Shrinking database");
+
+        // Compact the database
+        engine.Shrink();
+    }
+
+    public static void MigrateDatabase()
+    {
+        var realmConfiguration = new RealmConfiguration($"{Database.DatabaseFile}");
+
+        var realm = Realm.GetInstance(realmConfiguration);
+
+        if (!File.Exists(DatabaseFile)) 
+            return;
+        
+        using var connection = new SqlCeConnection($"Data Source={DatabaseFile}");
+
+        connection.Open();
+
+        var settings = connection.Query<Setting>("SELECT * FROM Setting").OrderBy(s => s.Version).ToList();
+        var categories = connection.Query<Category>("SELECT * FROM Category").ToList();
+        var feeds = connection.Query<Feed>("SELECT * FROM Feed").ToList();
+        var feedItems = connection.Query<FeedItem>("SELECT * FROM FeedItem").ToList();
+
+        realm.Write(() =>
+        {
+            foreach (var category in categories)
+            {
+                category.Feeds = feeds.Where(f => f.CategoryId == category.Id).ToList();
+            }
+
+            foreach (var feed in feeds)
+            {
+                feed.Category = categories.FirstOrDefault(c => c.Id == feed.CategoryId);
+            }
+
+            foreach (var feedItem in feedItems)
+            {
+                var feed = feeds.First(f => f.Id == feedItem.FeedId);
+
+                feed.Items.Add(feedItem);
+            }
+
+            realm.Add(feeds);
+            realm.Add(categories);
+            realm.Add(settings, true);
+        });
+
+        connection.Close();
+
+        File.Move(DatabaseFile, DatabaseFile + "_bak");
+    }
+
+    private static void ExecuteScript(string scriptText)
+    {
+        // Create a database connection
+        using var connection = new SqlCeConnection($"Data Source={DatabaseFile}");
+        // Open the connection
+        connection.Open();
+
+        // Setup the delimiters
+        var delimiters = new[] { "\r\nGO\r\n" };
+
+        // Split the script at the delimiters
+        var statements = scriptText.Split(delimiters, StringSplitOptions.RemoveEmptyEntries);
+
+        // Loop over each statement in the script
+        foreach (var statement in statements)
+        {
+            // Execute the statement
+            using var command = new SqlCeCommand(statement, connection);
+            command.ExecuteNonQuery();
+        }
+    }
+}