Merge pull request #35 from linq2db/feature/support_linq2db3.X

Added support linq2db 3.X

Author: sdanyliv

Build/linq2db.Default.props

@@ -1,6 +1,6 @@
 <Project>
 	<PropertyGroup>
-		<Version>2.0.6</Version>
+		<Version>3.0.0</Version>
 
 		<Description>Allows to execute Linq to DB (linq2db) queries in Entity Framework Core DbContext.</Description>
 		<Title>Linq to DB (linq2db) extensions for Entity Framework Core</Title>

NuGet/linq2db.EntityFrameworkCore.nuspec

@@ -15,8 +15,8 @@
 		<license type="file">MIT-LICENSE.txt</license>
 		<dependencies>
 			<group targetFramework=".NETStandard2.1">
-				<dependency id="Microsoft.EntityFrameworkCore.Relational" version="3.0.0" />
-				<dependency id="linq2db" version="2.9.6" />
+				<dependency id="Microsoft.EntityFrameworkCore.Relational" version="3.1.3" />
+				<dependency id="linq2db" version="3.0.0-preview.2" />
 			</group>
 		</dependencies>
 	</metadata>

Source/LinqToDB.EntityFrameworkCore/EFCoreMetadataReader.cs

@@ -243,13 +243,15 @@ private Sql.ExpressionAttribute GetDbFunctionFromMethodCall(Type type, MethodInf
 
 				if (!methodInfo.IsGenericMethodDefinition && !mi.GetCustomAttributes<Sql.ExpressionAttribute>().Any())
 				{
-					var objExpr = new SqlTransparentExpression(Expression.Constant(DefaultValue.GetValue(type), type), _mappingSource.FindMapping(type));
+					var value = Expression.Constant(DefaultValue.GetValue(type), type);
+
+					var objExpr = new SqlTransparentExpression(value, _mappingSource?.FindMapping(type));
 					var parameterInfos = methodInfo.GetParameters();
 					var parametersArray = parameterInfos
 						.Select(p =>
 							(SqlExpression)new SqlTransparentExpression(
 								Expression.Constant(DefaultValue.GetValue(p.ParameterType), p.ParameterType),
-								_mappingSource.FindMapping(p.ParameterType))).ToArray();
+								_mappingSource?.FindMapping(p.ParameterType))).ToArray();
 
 					var newExpression = _dependencies.MethodCallTranslatorProvider.Translate(_model, objExpr, methodInfo, parametersArray);
 					if (newExpression != null)
@@ -280,7 +282,7 @@ private Sql.ExpressionAttribute GetDbFunctionFromProperty(Type type, PropertyInf
 
 				if ((propInfo.GetMethod?.IsStatic != true) && !mi.GetCustomAttributes<Sql.ExpressionAttribute>().Any())
 				{
-					var objExpr = new SqlTransparentExpression(Expression.Constant(DefaultValue.GetValue(type), type), _mappingSource.FindMapping(propInfo));
+					var objExpr = new SqlTransparentExpression(Expression.Constant(DefaultValue.GetValue(type), type), _mappingSource?.FindMapping(propInfo));
 
 					var newExpression = _dependencies.MemberTranslatorProvider.Translate(objExpr, propInfo, propInfo.GetMemberType());
 					if (newExpression != null)

Source/LinqToDB.EntityFrameworkCore/LinqToDBForEFTools.cs

@@ -75,6 +75,9 @@ static bool InitializeInternal()
 
 			LinqExtensions.ExtensionsAdapter = new LinqToDBExtensionsAdapter();
 
+			// Set linq2db to allow multiple queries by default
+			Common.Configuration.Linq.AllowMultipleQuery = true;
+
 			return true;
 		}
 
@@ -262,18 +265,20 @@ public static DataConnection CreateLinqToDbConnection(this DbContext context,
 			if (transaction != null)
 			{
 				var dbTrasaction = transaction.GetDbTransaction();
-				if (provider.IsCompatibleConnection(dbTrasaction.Connection))
+				// TODO: we need API for testing current connection
+				//if (provider.IsCompatibleConnection(dbTrasaction.Connection))
 					dc = new LinqToDBForEFToolsDataConnection(context, provider, dbTrasaction, context.Model, TransformExpression);
 			}
 
 			if (dc == null)
 			{
 				var dbConnection = context.Database.GetDbConnection();
-				if (provider.IsCompatibleConnection(dbConnection))
+				// TODO: we need API for testing current connection
+				if (true /*provider.IsCompatibleConnection(dbConnection)*/)
 					dc = new LinqToDBForEFToolsDataConnection(context, provider, dbConnection, context.Model, TransformExpression);
 				else
 				{
-					dc = new LinqToDBForEFToolsDataConnection(context, provider, connectionInfo.ConnectionString, context.Model, TransformExpression);
+					//dc = new LinqToDBForEFToolsDataConnection(context, provider, connectionInfo.ConnectionString, context.Model, TransformExpression);
 				}
 			}
 
@@ -318,17 +323,21 @@ public static IDataContext CreateLinqToDbContext(this DbContext context,
 			if (transaction != null)
 			{
 				var dbTransaction = transaction.GetDbTransaction();
-				if (provider.IsCompatibleConnection(dbTransaction.Connection))
-					dc = new LinqToDBForEFToolsDataConnection(context, provider, dbTransaction, context.Model, TransformExpression);
+
+				// TODO: we need API for testing current connection
+				// if (provider.IsCompatibleConnection(dbTransaction.Connection))
+				dc = new LinqToDBForEFToolsDataConnection(context, provider, dbTransaction, context.Model, TransformExpression);
 			}
 
 			if (dc == null)
 			{
 				var dbConnection = context.Database.GetDbConnection();
-				if (provider.IsCompatibleConnection(dbConnection))
+				// TODO: we need API for testing current connection
+				if (true /*provider.IsCompatibleConnection(dbConnection)*/)
 					dc = new LinqToDBForEFToolsDataConnection(context, provider, context.Database.GetDbConnection(), context.Model, TransformExpression);
 				else
 				{
+					/*
 					// special case when we have to create data connection by itself
 					var dataContext = new LinqToDBForEFToolsDataContext(context, provider, connectionInfo.ConnectionString, context.Model, TransformExpression);
 
@@ -339,6 +348,7 @@ public static IDataContext CreateLinqToDbContext(this DbContext context,
 						dataContext.OnTraceConnection = t => Implementation.LogConnectionTrace(t, logger);
 						
 					return dataContext;
+					*/
 				}
 			}