Filter and middleware changes

- renamed and moved to subfolders
- more methods to override and customize behavior
- summary for methods updated

Author: alex-kulakov

…Orm.Web/SessionToActionProviderFilter.cs …e.Orm.Web/Filters/SessionActionFilter.csExtensions/Xtensive.Orm.Web/SessionToActionProviderFilter.cs renamed to Extensions/Xtensive.Orm.Web/Filters/SessionActionFilter.cs Extensions/Xtensive.Orm.Web/SessionToActionProviderFilter.cs renamed to Extensions/Xtensive.Orm.Web/Filters/SessionActionFilter.cs

@@ -11,9 +11,9 @@
 namespace Xtensive.Orm.Web.Filters
 {
   /// <summary>
-  /// Filter that 
+  /// DataObjects.Net Session providing action filter.
   /// </summary>
-  public class SessionToActionProviderFilter : IActionFilter, IAsyncActionFilter
+  public class SessionActionFilter : IActionFilter, IAsyncActionFilter
   {
     private SessionAccessor sessionAccessor;
     private IDisposable contextBindResource;
@@ -38,62 +38,65 @@ public async Task OnActionExecutionAsync(ActionExecutingContext context, ActionE
     }
 
     /// <summary>
-    /// Opens session.
+    /// Opens <see cref="Session"/>.
     /// </summary>
-    /// <param name="domain">Domain instance</param>
-    /// <param name="context">Action executing context</param>
+    /// <param name="domain"><see cref="Domain"/> instance.</param>
+    /// <param name="context">Action executing context.</param>
     /// <returns>Instance of <see cref="Session"/>.</returns>
     protected virtual Session OpenSession(Domain domain, ActionExecutingContext context) => domain.OpenSession();
 
     /// <summary>
-    /// Opens session asynchronously.
+    /// Opens <see cref="Session"/> asynchronously.
     /// </summary>
-    /// <param name="domain">Domain instance</param>
-    /// <param name="context">Action executing context</param>
+    /// <param name="domain">A <see cref="Domain"/> instance.</param>
+    /// <param name="context">The <see cref="ActionExecutingContext"/>.</param>
     /// <returns>Instance of <see cref="Session"/>.</returns>
     protected virtual Task<Session> OpenSessionAsync(Domain domain, ActionExecutingContext context) => domain.OpenSessionAsync();
 
     /// <summary>
-    /// Opens transaction scope.
+    /// Opens <see cref="TransactionScope"/>.
     /// </summary>
-    /// <param name="session">Domain instance.</param>
-    /// <param name="context">Action executing context.</param>
+    /// <param name="session">The <see cref="Session"/> to open transaction scope.</param>
+    /// <param name="context">The <see cref="ActionExecutingContext"/>.</param>
     /// <returns>Instance of <see cref="TransactionScope"/>.</returns>
     protected virtual TransactionScope OpenTransaction(Session session, ActionExecutingContext context) =>
       session.OpenTransaction();
 
     /// <summary>
-    /// Opens transaction scope asynchronously.
+    /// Opens <see cref="TransactionScope"/> asynchronously.
     /// </summary>
-    /// <param name="session">Domain instance.</param>
-    /// <param name="context">Action executing context.</param>
+    /// <param name="session">The <see cref="Session"/> to open transaction scope.</param>
+    /// <param name="context">The <see cref="ActionExecutingContext"/>.</param>
     /// <returns>Instance of <see cref="TransactionScope"/>.</returns>
     protected virtual async Task<TransactionScope> OpenTransactionAsync(Session session, ActionExecutingContext context) =>
       await session.OpenTransactionAsync();
 
     /// <summary>
-    /// Executes before <see cref="TransactionScope"/> dispose.
+    /// Executes before <paramref name="transactionScope"/> disposing.
     /// </summary>
     /// <param name="transactionScope">The transaction scope which is about to be disposed.</param>
-    /// <param name="session">The session transaction scope belongs to.</param>
+    /// <param name="session">The <see cref="Session"/> transaction scope belongs to.</param>
     /// <param name="context">The <see cref="ActionExecutedContext"/>.</param>
     protected virtual void OnTransactionScopeDisposing(TransactionScope transactionScope, Session session, ActionExecutedContext context)
     {
+      if (context.Exception == null || CompleteTransactionOnException(context.Exception, context)) {
+        transactionScope.Complete();
+      }
     }
 
     /// <summary>
-    /// Executes after <see cref="TransactionScope"/> is dispose.
+    /// Executes after <see cref="TransactionScope"/> is disposed.
     /// </summary>
-    /// <param name="session">The session the disposed transaction scope belonged to.</param>
+    /// <param name="session">The <see cref="Session"/> the disposed transaction scope belonged to.</param>
     /// <param name="context">The <see cref="ActionExecutedContext"/>.</param>
     protected virtual void OnTransactionScopeDisposed(Session session, ActionExecutedContext context)
     {
     }
 
     /// <summary>
-    /// Executes before <see cref="Session"/> dispose.
+    /// Executes before <paramref name="session"/> disposing.
     /// </summary>
-    /// <param name="session">The session which is about to be disposed.</param>
+    /// <param name="session">The <see cref="Session"/> which is about to be disposed.</param>
     /// <param name="context">The <see cref="ActionExecutedContext"/>.</param>
     protected virtual void OnSessionDisposing(Session session, ActionExecutedContext context)
     {
@@ -107,18 +110,29 @@ protected virtual void OnSessionDisposed(ActionExecutedContext context)
     {
     }
 
+
+    /// <summary>
+    /// Allows to define what exceptions will not leat to transaction rollback.
+    /// </summary>
+    /// <param name="exception">The exception thrown by action.</param>
+    /// <param name="context">The <see cref="ActionExecutedContext"/>.</param>
+    /// <returns><see langword="true"/> for complete transaction scope, otherwise, <see langword="false"/>.</returns>
+    protected virtual bool CompleteTransactionOnException(Exception exception, ActionExecutedContext context) => false;
+
     //internal void Persist(PersistReason reason) => Persist(reason, false).GetAwaiter().GetResult();
     private async ValueTask ExecuteBeforeAction(ActionExecutingContext context, bool isAsync)
     {
       var actionParameters = context.ActionDescriptor.Parameters;
 
+      skipResourcesRelease = true;
+
       //this search can probably be improved by caching action names with needed parameters
       foreach (var p in actionParameters) {
         if (p.ParameterType == WellKnownTypes.SessionAccessorType) {
           // trying to get registered accessor as service
           var accessor = GetSessionAccesorFromServices(context.HttpContext);
           if (accessor != null) {
-            // this is registered as service and probably filled with middlewere
+            // this is registered as service and probably filled with middleware
             skipResourcesRelease = true;
             sessionAccessor = accessor;
             if (accessor.ContextIsBound) {
@@ -199,12 +213,10 @@ private async ValueTask<IDisposable> CreateSessionAndBindContext(SessionAccessor
     private static Domain GetDomainFromServices(HttpContext context)
     {
       var domain = (Domain) context.RequestServices.GetService(WellKnownTypes.DomainType);
-      return domain == null
-        ? throw new InvalidOperationException("Domain is not found among registered services.")
-        : domain;
+      return domain ?? throw new InvalidOperationException("Domain is not found among registered services.");
     }
 
     private static SessionAccessor GetSessionAccesorFromServices(HttpContext context) =>
       (SessionAccessor) context.RequestServices.GetService(WellKnownTypes.SessionAccessorType);
   }
-}
+}

…tensive.Orm.Web/OpenSessionMiddlewere.cs ….Web/Middleware/OpenSessionMiddleware.csExtensions/Xtensive.Orm.Web/OpenSessionMiddlewere.cs renamed to Extensions/Xtensive.Orm.Web/Middleware/OpenSessionMiddleware.cs Extensions/Xtensive.Orm.Web/OpenSessionMiddlewere.cs renamed to Extensions/Xtensive.Orm.Web/Middleware/OpenSessionMiddleware.cs

@@ -7,13 +7,12 @@
 using System.Threading.Tasks;
 using System.Runtime.ExceptionServices;
 
-namespace Xtensive.Orm.Web
+namespace Xtensive.Orm.Web.Middleware
 {
-
   /// <summary>
   /// DataObjects.Net Session providing middleware.
   /// </summary>
-  public class OpenSessionMiddlewere
+  public class OpenSessionMiddleware
   {
     private readonly RequestDelegate next;
 
@@ -50,8 +49,13 @@ public async Task Invoke(HttpContext context)
           }
           finally {
             RemoveResourcesFromContext(context);
+            await OnTransactionDisposingAsync(transaction, session, context);
             await transaction.DisposeAsync();
+            await OnTransactionDisposedAsync(session, context);
+
+            await OnSessionDisposingAsync(session, context);
             await session.DisposeAsync();
+            await OnSessionDisposedAsync(context);
           }
         }
       }
@@ -61,22 +65,54 @@ public async Task Invoke(HttpContext context)
     }
 
     /// <summary>
-    /// Opens session asynchronously.
+    /// Opens <see cref="Session"/> asynchronously.
     /// </summary>
-    /// <param name="domain">Domain instance</param>
-    /// <param name="context">Action executing context</param>
+    /// <param name="domain">A <see cref="Domain"/> instance.</param>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
     /// <returns>Instance of <see cref="Session"/>.</returns>
     protected virtual Task<Session> OpenSessionAsync(Domain domain, HttpContext context) => domain.OpenSessionAsync();
 
     /// <summary>
-    /// Opens transaction scope asynchronously.
+    /// Opens <see cref="TransactionScope"/> asynchronously.
     /// </summary>
-    /// <param name="session">Domain instance.</param>
-    /// <param name="context">Action executing context.</param>
+    /// <param name="session">A <see cref="Session"/> instance to open transaction for.</param>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
     /// <returns>Instance of <see cref="TransactionScope"/>.</returns>
     protected virtual async Task<TransactionScope> OpenTransactionAsync(Session session, HttpContext context) =>
       await session.OpenTransactionAsync();
 
+    /// <summary>
+    /// Executes before <paramref name="transactionScope"/> disposing.
+    /// </summary>
+    /// <param name="transactionScope">The <see cref="TransactionScope"/> to be disposed.</param>
+    /// <param name="session">The <see cref="Session"/> the <paramref name="transactionScope"/> belongs to.</param>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
+    /// <returns>Task performing this operation.</returns>
+    protected virtual ValueTask OnTransactionDisposingAsync(TransactionScope transactionScope, Session session, HttpContext context) => default;
+
+    /// <summary>
+    /// Executes after <see cref="TransactionScope"/> disposed.
+    /// </summary>
+    /// <param name="session">The <see cref="Session"/> disposed scoped belonged too.</param>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
+    /// <returns>Task performing this operation.</returns>
+    protected virtual ValueTask OnTransactionDisposedAsync(Session session, HttpContext context) => default;
+
+    /// <summary>
+    /// Executes before <paramref name="session"/> disposing.
+    /// </summary>
+    /// <param name="session">The <see cref="Session"/> to be disposed.</param>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
+    /// <returns>Task performing this operation.</returns>
+    protected virtual ValueTask OnSessionDisposingAsync(Session session, HttpContext context) => default;
+
+    /// <summary>
+    /// Executes after <see cref="Session"/> disposed.
+    /// </summary>
+    /// <param name="context">The <see cref="HttpContext"/>.</param>
+    /// <returns>Task performing this operation.</returns>
+    protected virtual ValueTask OnSessionDisposedAsync(HttpContext context) => default;
+
     /// <summary>
     /// Determines whether transaction should be completed even though exception appeared.
     /// </summary>
@@ -108,18 +144,16 @@ private static void RemoveResourcesFromContext(HttpContext context)
     private static Domain GetDomainFromServices(HttpContext context)
     {
       var domain = (Domain) context.RequestServices.GetService(WellKnownTypes.DomainType);
-      return domain == null
-        ? throw new InvalidOperationException("Domain is not found among registered services.")
-        : domain;
+      return domain ?? throw new InvalidOperationException("Domain is not found among registered services.");
     }
 
     /// <summary>
-    /// Creates an instance of <see cref="OpenSessionMiddlewere"/>
+    /// Creates an instance of <see cref="OpenSessionMiddleware"/>
     /// </summary>
     /// <param name="next"></param>
-    public OpenSessionMiddlewere(RequestDelegate next)
+    public OpenSessionMiddleware(RequestDelegate next)
     {
       this.next = next;
     }
   }
-}
+}