WIP: Make QueryProvider.Connection virtual

src/Data/ConnectionHelper.cs

@@ -1,8 +1,6 @@
 using System;
-using System.Collections.Generic;
 using System.Data;
 using System.Data.Common;
-using System.Text;
 
 namespace Kros.KORM.Data
 {
@@ -45,9 +43,6 @@ protected virtual void Dispose(bool disposing)
             }
         }
 
-        public void Dispose()
-        {
-            Dispose(true);
-        }
+        public void Dispose() => Dispose(true);
     }
 }

src/Data/TransactionHelper.cs

@@ -1,4 +1,5 @@
-using Kros.Utils;
+using Kros.KORM.Properties;
+using Kros.Utils;
 using System;
 using System.Collections.Generic;
 using System.Data;
@@ -13,34 +14,35 @@ namespace Kros.KORM.Data
     internal class TransactionHelper
     {
         public const IsolationLevel DefaultIsolationLevel = IsolationLevel.ReadCommitted;
-        private const int TIMEOUT_DEFAULT = 30;
-
-        private readonly DbConnection _connection;
-        private Transaction _topTransaction;
-        private bool _canCommit = true;
-        private readonly Stack<ITransaction> _transactions = new Stack<ITransaction>();
+        private const int DefaultCommandTimeout = 30;
 
         #region Nested types
 
         private class Transaction : ITransaction
         {
-            private readonly ConnectionHelper _connectionHelper;
+            private readonly DbConnection _connection;
+            private readonly bool _closeConnection;
             private readonly Lazy<DbTransaction> _transaction;
             private readonly TransactionHelper _transactionHelper;
             private bool _wasCommitOrRollback = false;
 
-            public Transaction(TransactionHelper transactionHelper, ConnectionHelper connectionHelper, IsolationLevel isolationLevel)
+            public Transaction(
+                TransactionHelper transactionHelper,
+                DbConnection connection,
+                bool closeConnection,
+                IsolationLevel isolationLevel)
             {
-                _connectionHelper = connectionHelper;
-                _transaction = new Lazy<DbTransaction>(() => connectionHelper.Connection.BeginTransaction(isolationLevel));
                 _transactionHelper = transactionHelper;
+                _connection = connection;
+                _closeConnection = closeConnection;
+                _transaction = new Lazy<DbTransaction>(() => _connection.BeginTransaction(isolationLevel));
             }
 
             public void Commit()
             {
-                _wasCommitOrRollback = true;
                 if (_transactionHelper.CanCommitTransaction)
                 {
+                    _wasCommitOrRollback = true;
                     _transaction.Value.Commit();
                     _transactionHelper.EndTransaction(true);
                 }
@@ -53,7 +55,7 @@ public void Rollback()
                 _transactionHelper.EndTransaction(false);
             }
 
-            public int CommandTimeout { get; set; } = TIMEOUT_DEFAULT;
+            public int CommandTimeout { get; set; } = DefaultCommandTimeout;
 
             public static implicit operator DbTransaction(Transaction transaction)
                 => transaction?._transaction.Value;
@@ -69,7 +71,10 @@ public void Dispose()
                 {
                     _transaction.Value.Dispose();
                 }
-                _connectionHelper.Dispose();
+                if (_closeConnection)
+                {
+                    _connection.Close();
+                }
             }
         }
 
@@ -87,8 +92,14 @@ public NestedTransaction(TransactionHelper transactionHelper, int timeout)
 
             public void Commit()
             {
+                _wasCommitOrRollback = true;
                 _transactionHelper.EndTransaction(true);
+            }
+
+            public void Rollback()
+            {
                 _wasCommitOrRollback = true;
+                _transactionHelper.EndTransaction(false);
             }
 
             public void Dispose()
@@ -99,39 +110,39 @@ public void Dispose()
                 }
             }
 
-            public void Rollback()
-            {
-                _transactionHelper.EndTransaction(false);
-                _wasCommitOrRollback = true;
-            }
-
             public int CommandTimeout
             {
-                get => _timeout;
-                set { }
+                get => DefaultCommandTimeout;
+                set => throw new InvalidOperationException(Resources.NestedTransactionCommandTimeoutIsReadonly);
             }
         }
 
         #endregion
 
-        public TransactionHelper(DbConnection connection)
+        private readonly DbConnection _connection;
+        private readonly bool _closeConnection;
+        private Transaction _topTransaction;
+        private bool _canCommit = true;
+        private readonly Stack<ITransaction> _transactions = new Stack<ITransaction>();
+
+        public TransactionHelper(DbConnection connection, bool closeConnection)
         {
             _connection = Check.NotNull(connection, nameof(connection));
+            _closeConnection = closeConnection;
         }
 
         public ITransaction BeginTransaction(IsolationLevel isolationLevel)
         {
             if (_transactions.Count == 0)
             {
-                _topTransaction = new Transaction(this, new ConnectionHelper(_connection), isolationLevel);
+                _topTransaction = new Transaction(this, _connection, _closeConnection, isolationLevel);
                 _transactions.Push(_topTransaction);
                 _canCommit = true;
             }
             else
             {
                 _transactions.Push(new NestedTransaction(this, _topTransaction.CommandTimeout));
             }
-
             return _transactions.Peek();
         }
 
@@ -145,7 +156,6 @@ private void EndTransaction(bool success)
         {
             _canCommit &= success;
             _transactions.Pop();
-
             if (!_transactions.Any())
             {
                 _topTransaction = null;
@@ -160,7 +170,6 @@ public DbCommand CreateCommand()
                 cmd.Transaction = _topTransaction;
                 cmd.CommandTimeout = _topTransaction.CommandTimeout;
             }
-
             return cmd;
         }
     }

src/Database.cs

@@ -60,8 +60,14 @@ public partial class Database : IDatabase
         /// <summary>
         /// Builder for creating <see cref="IDatabase"/> instance.
         /// </summary>
+        [Obsolete("Use CreateBuilder method.")]
         public static IDatabaseBuilder Builder => new DatabaseBuilder();
 
+        /// <summary>
+        /// Creates a builder for creating <see cref="IDatabase"/> instance.
+        /// </summary>
+        public static IDatabaseBuilder CreateBuilder() => new DatabaseBuilder();
+
         #endregion
 
         #region Private fields

src/IAuthTokenProvider.cs

@@ -0,0 +1,14 @@
+namespace Kros.KORM
+{
+    /// <summary>
+    /// Support for token-based authentication for SQL Server.
+    /// </summary>
+    public interface IAuthTokenProvider
+    {
+        /// <summary>
+        /// Returns authentication token, or <see langword="null" /> value, if token can not be obtained.
+        /// </summary>
+        /// <returns>Authentication token.</returns>
+        string GetToken();
+    }
+}

src/Query/Providers/QueryProvider.cs

@@ -16,6 +16,7 @@
 using System.Collections.Generic;
 using System.Data;
 using System.Data.Common;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
@@ -122,7 +123,7 @@ protected QueryProvider(
             InitSqlExpressionVisitor(Check.NotNull(sqlGeneratorFactory, nameof(sqlGeneratorFactory)));
             IsExternalConnection = false;
             _modelBuilder = Check.NotNull(modelBuilder, nameof(modelBuilder));
-            _transactionHelper = new Lazy<TransactionHelper>(() => new TransactionHelper(Connection));
+            _transactionHelper = new Lazy<TransactionHelper>(TransactionHelperFactory);
         }
 
         /// <summary>
@@ -147,11 +148,17 @@ protected QueryProvider(
 
             InitSqlExpressionVisitor(Check.NotNull(sqlGeneratorFactory, nameof(sqlGeneratorFactory)));
             IsExternalConnection = true;
-            _transactionHelper = new Lazy<TransactionHelper>(() => new TransactionHelper(Connection));
+            _transactionHelper = new Lazy<TransactionHelper>(TransactionHelperFactory);
         }
 
         private void InitSqlExpressionVisitor(ISqlExpressionVisitorFactory sqlGeneratorFactory)
-            => _sqlExpressionVisitor = new Lazy<ISqlExpressionVisitor>(() => sqlGeneratorFactory.CreateVisitor(Connection));
+            => _sqlExpressionVisitor = new Lazy<ISqlExpressionVisitor>(() => sqlGeneratorFactory.CreateVisitor(GetConnection()));
+
+        private TransactionHelper TransactionHelperFactory()
+        {
+            DbConnection connection = GetConnection();
+            return new TransactionHelper(connection, !connection.State.HasFlag(ConnectionState.Open));
+        }
 
         #endregion
 
@@ -190,7 +197,7 @@ public void SetParameterDbType(DbParameter parameter, string tableName, string c
         private TableSchema LoadTableSchema(string tableName)
         {
             IDatabaseSchemaLoader schemaLoader = GetSchemaLoader();
-            TableSchema tableSchema = schemaLoader.LoadTableSchema(Connection, tableName);
+            TableSchema tableSchema = schemaLoader.LoadTableSchema(GetConnection(), tableName);
             return tableSchema
                 ?? throw new InvalidOperationException(string.Format(Resources.QueryProviderCouldNotGetTableSchema, tableName));
         }
@@ -541,7 +548,7 @@ public IIdGeneratorsForDatabaseInit GetIdGeneratorsForDatabaseInit()
 
         private IDbConnection GetConnectionForIdGenerator()
         {
-            var connection = (Connection as ICloneable).Clone() as DbConnection;
+            var connection = (GetConnection() as ICloneable).Clone() as DbConnection;
             try
             {
                 connection.Open();
@@ -631,24 +638,27 @@ public TResult Execute<TResult>(Expression expression)
         /// Vráti spojenie na databázu s ktorou trieda pracuje. Ak trieda bola vytvorená iba so zadaným
         /// connection string-om, je vytvorené nové spojenie.
         /// </summary>
-        protected DbConnection Connection
+        [Obsolete("Use GetConnection() method.")]
+        protected DbConnection Connection => GetConnection();
+
+        /// <summary>
+        /// Returns (creates if needed) connection.
+        /// </summary>
+        /// <returns><see cref="DbConnection"/> instance.</returns>
+        protected virtual DbConnection GetConnection()
         {
-            get
+            if (_connection == null)
             {
-                if (_connection == null)
-                {
-                    _connection = DbProviderFactory.CreateConnection();
-                    _connection.ConnectionString = _connectionSettings.ConnectionString;
-                }
-                return _connection;
+                _connection = DbProviderFactory.CreateConnection();
+                _connection.ConnectionString = _connectionSettings.ConnectionString;
             }
+            return _connection;
         }
 
-        private Data.ConnectionHelper OpenConnection()
-        {
-            return new Data.ConnectionHelper(Connection);
-        }
+        private Data.ConnectionHelper OpenConnection() => new Data.ConnectionHelper(GetConnection());
 
+        [SuppressMessage("Security", "CA2100:Review SQL queries for security vulnerabilities",
+            Justification = "Query is external or generated.")]
         private DbCommandInfo CreateCommand<T>(IQuery<T> query)
         {
             DbCommand command = _transactionHelper.Value.CreateCommand();
@@ -671,6 +681,8 @@ private DbCommandInfo CreateCommand<T>(IQuery<T> query)
         protected internal void SetQueryFilter<T>(IQuery<T> query, ISqlExpressionVisitor sqlVisitor)
             => (query as IQueryBaseInternal).ApplyQueryFilter(_databaseMapper, sqlVisitor);
 
+        [SuppressMessage("Security", "CA2100:Review SQL queries for security vulnerabilities",
+            Justification = "Query is external or generated.")]
         private DbCommand CreateCommand(string commandText, CommandParameterCollection parameters)
         {
             DbCommand command = _transactionHelper.Value.CreateCommand();
@@ -683,7 +695,6 @@ private DbCommand CreateCommand(string commandText, CommandParameterCollection p
                     AddCommandParameter(command, parameter);
                 }
             }
-
             return command;
         }