Audit Changes in a Manually Created ObjectSpace

• Apr 27, 2022
• 2 minutes to read

Object Space API helps you manage data stores in XAF applications. To access the API, you usually need to call the XafApplication.CreateObjectSpace method that initializes an XPObjectSpace object. The Audit Trail Module then automatically tracks all changes in the new object space.

If you create an XPObjectSpace manually (for example, a non-secured object space in a secured application), the Audit Trail Module does not log changes made within this XPObjectSpace. To enable audit, register the object space and handle its events as shown below:

C#

using DevExpress.ExpressApp;
using DevExpress.ExpressApp.Actions;
using DevExpress.ExpressApp.Security.ClientServer;
using DevExpress.ExpressApp.Xpo;
using DevExpress.Persistent.AuditTrail;
using DevExpress.Persistent.Base;
using MySolution.Module.BusinessObjects;
using System;
using System.Linq;

namespace MySolution.Module.Win.Controllers {
    public class CustomWinController : ObjectViewController<DetailView,Contact> {
        public CustomWinController() {
             var myAction1 = new SimpleAction(this, "MyWinAction1", PredefinedCategory.Edit);
              myAction1.Execute += MyAction1_Execute;
        }

        private void MyAction1_Execute(object sender, SimpleActionExecuteEventArgs e) {
            SecuredObjectSpaceProvider securedObjectSpaceProvider = (SecuredObjectSpaceProvider)
              Application.ObjectSpaceProviders.First(
                p => p is SecuredObjectSpaceProvider
              );
            // Create a 'free' XPObjectSpace
            IObjectSpace unsecuredObjectSpace = securedObjectSpaceProvider.CreateNonsecuredObjectSpace(); 
            var _contact = (Contact)unsecuredObjectSpace.GetObject(View.CurrentObject);

            AuditTrailService.Instance.BeginSessionAudit(((XPObjectSpace)unsecuredObjectSpace).Session, AuditTrailStrategy.OnObjectChanged);
            unsecuredObjectSpace.Committed += new EventHandler(ObjectSpace_Committed);
            unsecuredObjectSpace.Reloaded += new EventHandler(ObjectSpace_Reloaded);

            _contact.LastName = "NewName" + DateTime.Now.Millisecond;
            unsecuredObjectSpace.CommitChanges();
        }

        private void ObjectSpace_Reloaded(object sender, EventArgs e) {
            AuditTrailService.Instance.EndSessionAudit(((XPObjectSpace)sender).Session);
            AuditTrailService.Instance.BeginSessionAudit(((XPObjectSpace)sender).Session, AuditTrailStrategy.OnObjectChanged);
        }
        private void ObjectSpace_Committed(object sender, EventArgs e) {
            AuditTrailService.Instance.SaveAuditData(((XPObjectSpace)sender).Session);
            AuditTrailService.Instance.BeginSessionAudit(((XPObjectSpace)sender).Session, AuditTrailStrategy.OnObjectChanged);
        }

    }
} 

VB.NET

Imports DevExpress.ExpressApp
Imports DevExpress.ExpressApp.Actions
Imports DevExpress.ExpressApp.Security.ClientServer
Imports DevExpress.ExpressApp.Xpo
Imports DevExpress.Persistent.AuditTrail
Imports DevExpress.Persistent.Base
Imports System
Imports System.Linq
Public Class ViewController1
    Inherits ViewController

    Public Sub New()

        Dim simpleAction1 = New SimpleAction(Me, "MyWinAction1", PredefinedCategory.Edit)
        simpleAction1.Caption = "MyChangeObject"
        AddHandler simpleAction1.Execute, AddressOf SimpleAction1_Execute

    End Sub

    Private Sub SimpleAction1_Execute(sender As Object, e As SimpleActionExecuteEventArgs)

        Dim _securedObjectSpaceProvider As SecuredObjectSpaceProvider = CType(Application.ObjectSpaceProviders.First(Function(p) TypeOf p Is SecuredObjectSpaceProvider), SecuredObjectSpaceProvider)

        ' Create a 'free' XPObjectSpace
        Dim unsecuredObjectSpace As XPObjectSpace = _securedObjectSpaceProvider.CreateNonsecuredObjectSpace()
        Dim _contact = CType(unsecuredObjectSpace.GetObject(View.CurrentObject), Contact)

        AuditTrailService.Instance.BeginSessionAudit(unsecuredObjectSpace.Session, AuditTrailStrategy.OnObjectChanged)
        AddHandler unsecuredObjectSpace.Committed, AddressOf ObjectSpace_Committed
        AddHandler unsecuredObjectSpace.Reloaded, AddressOf ObjectSpace_Reloaded

        _contact.LastName = "NewName" + DateTime.Now.Millisecond.ToString()
        unsecuredObjectSpace.CommitChanges()
    End Sub

    Private Sub ObjectSpace_Reloaded(ByVal sender As Object, ByVal e As EventArgs)
        AuditTrailService.Instance.EndSessionAudit((CType(sender, XPObjectSpace)).Session)
        AuditTrailService.Instance.BeginSessionAudit((CType(sender, XPObjectSpace)).Session, AuditTrailStrategy.OnObjectChanged)
    End Sub

    Private Sub ObjectSpace_Committed(ByVal sender As Object, ByVal e As EventArgs)
        AuditTrailService.Instance.SaveAuditData((CType(sender, XPObjectSpace)).Session)
        AuditTrailService.Instance.BeginSessionAudit((CType(sender, XPObjectSpace)).Session, AuditTrailStrategy.OnObjectChanged)
    End Sub
End Class