Use the Security System

Sep 12, 2023
7 minutes to read

This article explains how to implement the Security System in your application. The system applies the SecurityStrategyComplex security strategy. According to this strategy, the application users have roles with different permission sets. For more information about permissions, see the following article: Security (Access Control & Authentication).

The instructions below describe how to do the following:

Enable the AuthenticationStandard authentication type.
Create an administrator user and a common user in code.
Create a user and a role at runtime.

The administrator has a full-access permission set. The user has a limited permission set. The administrator can create User objects and Role objects, specify Permissions for them, and then assign Roles to Users at runtime.

With AuthenticationStandard authentication type, the Security System uses the internal XAF authentication mechanism and stores user credentials in the application’s database. Users need to input their name and password in the login form before application startup.

Note

Before you proceed, take a moment to review this lesson:

Supply Initial Data

Implement Standard Authentication in Code

In the MySolution.Module\Business Objects folder, create the ApplicationUser class. Replace the generated class declaration with the following code:

using System.Collections.ObjectModel;
using System.ComponentModel;
using DevExpress.ExpressApp;
using DevExpress.ExpressApp.Security;
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;

namespace MySolution.Module.BusinessObjects;

[DefaultProperty(nameof(UserName))]
public class ApplicationUser : PermissionPolicyUser, ISecurityUserWithLoginInfo
{
    public ApplicationUser() : base()
    {
        UserLogins = new ObservableCollection<ApplicationUserLoginInfo>();
    }

    [Browsable(false)]
    [DevExpress.ExpressApp.DC.Aggregated]
    public virtual IList<ApplicationUserLoginInfo> UserLogins { get; set; }

    IEnumerable<ISecurityUserLoginInfo> IOAuthSecurityUser.UserLogins => UserLogins.OfType<ISecurityUserLoginInfo>();

    ISecurityUserLoginInfo ISecurityUserWithLoginInfo.CreateUserLoginInfo(string loginProviderName, string providerUserKey)
    {
        ApplicationUserLoginInfo result = ((IObjectSpaceLink)this).ObjectSpace.CreateObject<ApplicationUserLoginInfo>();
        result.LoginProviderName = loginProviderName;
        result.ProviderUserKey = providerUserKey;
        result.User = this;
        return result;
    }
}

You inherit this class from the PermissionPolicyUser class that defines an XAF user with a list of associated security roles.

In the same manner, create the ApplicationUserLoginInfo class.

using DevExpress.ExpressApp.ConditionalAppearance;
using DevExpress.ExpressApp.Security;
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace MySolution.Module.BusinessObjects;

[Table("PermissionPolicyUserLoginInfo")]
public class ApplicationUserLoginInfo : ISecurityUserLoginInfo
{

    public ApplicationUserLoginInfo() { }

    [Browsable(false)]
    public virtual Guid ID { get; protected set; }

    [Appearance("PasswordProvider", Enabled = false, Criteria = 
    "!(IsNewObject(this)) and LoginProviderName == '" + SecurityDefaults.PasswordAuthentication + "'", Context = "DetailView")]
    public virtual string LoginProviderName { get; set; }

    [Appearance("PasswordProviderUserKey", Enabled = false, Criteria = 
    "!(IsNewObject(this)) and LoginProviderName == '" + SecurityDefaults.PasswordAuthentication + "'", Context = "DetailView")]
    public virtual string ProviderUserKey { get; set; }

    [Browsable(false)]
    public virtual Guid UserForeignKey { get; set; }

    [Required]
    [ForeignKey(nameof(UserForeignKey))]
    public virtual ApplicationUser User { get; set; }

    object ISecurityUserLoginInfo.User => User;
}

Go to the MySolution.Module\MySolutionDbContext file and add properties of ApplicationUser and ApplicationUserLoginInfo types to DbSet:

public class MySolutionEFCoreDbContext : DbContext {
    //...
    public DbSet<ApplicationUser> Users { get; set; }
    public DbSet<ApplicationUserLoginInfo> UserLoginInfos { get; set; }
}

Add a migration and update the database. See the following section for details: Use a DBMS: Setup Migrations.

Enable Standard Authentication in the platform-specific Startup files:

C# (ASP.NET Core Blazor)
C# (Windows Forms)

// ...
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;
using MySolution.Module.BusinessObjects;

public class Startup {
// ...
    public void ConfigureServices(IServiceCollection services) {
        // ...
        services.AddXaf(Configuration, builder => {
             // ...
             builder.ObjectSpaceProviders
                 .AddSecuredEFCore().WithDbContext<MySolution.Module.BusinessObjects.MySolutionEFCoreDbContext>((serviceProvider, options) => {
                     // ...
                 })
                 .AddNonPersistent();
             builder.Security
                 .UseIntegratedMode(options => {
                     options.RoleType = typeof(PermissionPolicyRole);
                     options.UserType = typeof(ApplicationUser);
                     options.UserLoginInfoType = typeof(ApplicationUserLoginInfo);
                     options.SupportNavigationPermissionsForTypes = false;
             })
             .AddPasswordAuthentication(options => options.IsSupportChangePassword = true);
        });
        services.AddAuthentication(CookieAuthenticationDefaults.AuthenticationScheme)
            .AddCookie(options => {
                options.LoginPath = "/LoginPage";
            });
    }
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env) {
        //...
        app.UseRequestLocalization();
        //..
        app.UseAuthentication();
        app.UseAuthorization();
        //...
    }
}

// ...
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;
using MySolution.Module.BusinessObjects;

public class ApplicationBuilder : IDesignTimeApplicationFactory {
    public static WinApplication BuildApplication(string connectionString) {
    var builder = WinApplication.CreateBuilder();
    builder.UseApplication<MySolutionWindowsFormsApplication>();
    builder.ObjectSpaceProviders
         .AddSecuredEFCore().WithDbContext<MySolution.Module.BusinessObjects.MySolutionEFCoreDbContext>((application, options) => {
             // ...
         })
         // ...
     builder.Security
         .UseIntegratedMode(options =>
         {
             options.RoleType = typeof(PermissionPolicyRole);
             options.UserType = typeof(ApplicationUser);
             options.UserLoginInfoType = typeof(ApplicationUserLoginInfo);
             options.SupportNavigationPermissionsForTypes = false;
         })
     .UsePasswordAuthentication();               
     //...
    }
}

Expand the MySolution.Module project in the Solution Explorer and go to the DatabaseUpdate folder. Open the Updater.cs file and create the Administrator user in the ModuleUpdater.UpdateDatabaseAfterUpdateSchema method.

//...
using DevExpress.ExpressApp.Security;
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;
using MySolution.Module.BusinessObjects;

public class Updater : DevExpress.ExpressApp.Updating.ModuleUpdater {
    //...
    public override void UpdateDatabaseAfterUpdateSchema() {
        base.UpdateDatabaseAfterUpdateSchema();
        //...
        ApplicationUser userAdmin = ObjectSpace.FirstOrDefault<ApplicationUser>(u => u.UserName == "Admin");
        if (userAdmin == null)
        {
            userAdmin = ObjectSpace.CreateObject<ApplicationUser>();
            userAdmin.UserName = "Admin";
            // Set a password if the standard authentication type is used
            userAdmin.SetPassword("");

            /* The UserLoginInfo object requires a user object Id (Oid).
               Commit the user object to the database before you create a UserLoginInfo object.
               This will correctly initialize the user key property. */

            ObjectSpace.CommitChanges(); //This line persists created object(s).
            ((ISecurityUserWithLoginInfo)userAdmin).CreateUserLoginInfo(SecurityDefaults.PasswordAuthentication, 
            ObjectSpace.GetKeyValueAsString(userAdmin));
        }
        // If a role with the Administrators name doesn't exist in the database, create this role.
        PermissionPolicyRole adminRole = 
        ObjectSpace.FirstOrDefault<PermissionPolicyRole>(r => r.Name == "Administrators");
        if (adminRole == null)
        {
            adminRole = ObjectSpace.CreateObject<PermissionPolicyRole>();
            adminRole.Name = "Administrators";
        }
        //Set the user's role to Administrative. This role has access to objects of all types.
        adminRole.IsAdministrative = true;
        userAdmin.Roles.Add(adminRole);

        ObjectSpace.CommitChanges(); //Uncomment this line to persist created object(s).
    }
}

In the same manner, create a common user.

//...
using DevExpress.ExpressApp.Security;
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;
using MySolution.Module.BusinessObjects;

public class Updater : DevExpress.ExpressApp.Updating.ModuleUpdater {
    //...
    public override void UpdateDatabaseAfterUpdateSchema() {
        base.UpdateDatabaseAfterUpdateSchema();
        //...
        ApplicationUser commonUser = ObjectSpace.FirstOrDefault<ApplicationUser>(u => u.UserName == "User");
        if (commonUser == null)
        {
            commonUser = ObjectSpace.CreateObject<ApplicationUser>();
            commonUser.UserName = "User";
            // Set a password if the standard authentication type is used
            commonUser.SetPassword("");

            /* The UserLoginInfo object requires a user object Id (Oid).
               Commit the user object to the database before you create a UserLoginInfo object.
               This will correctly initialize the user key property.*/

            ObjectSpace.CommitChanges(); //This line persists created object(s).

            ((ISecurityUserWithLoginInfo)commonUser).CreateUserLoginInfo(SecurityDefaults.PasswordAuthentication, 
            ObjectSpace.GetKeyValueAsString(commonUser));
        }
        PermissionPolicyRole defaultRole = CreateDefaultRole();
        commonUser.Roles.Add(defaultRole);
    }
}

Create a common user role and specify its permissions. This user only has access to the current user object.

 using MySolution.Module.BusinessObjects;
 using DevExpress.ExpressApp.SystemModule;
 //...

 public class Updater : DevExpress.ExpressApp.Updating.ModuleUpdater {
     //...
     public override void UpdateDatabaseAfterUpdateSchema() {
         base.UpdateDatabaseBeforeUpdateSchema();
     }

    private PermissionPolicyRole CreateDefaultRole()
    {
        PermissionPolicyRole defaultRole = 
        ObjectSpace.FirstOrDefault<PermissionPolicyRole>(role => role.Name == "Default");
        if (defaultRole == null)
        {
            defaultRole = ObjectSpace.CreateObject<PermissionPolicyRole>();
            defaultRole.Name = "Default";

            defaultRole.AddObjectPermissionFromLambda<ApplicationUser>(SecurityOperations.Read, 
            cm => cm.ID == (Guid)CurrentUserIdOperator.CurrentUserId(), SecurityPermissionState.Allow);
            defaultRole.AddNavigationPermission(@"Application/NavigationItems/Items/Default/Items/MyDetails", 
            SecurityPermissionState.Allow);
            defaultRole.AddMemberPermissionFromLambda<ApplicationUser>(SecurityOperations.Write, 
            "ChangePasswordOnFirstLogon", cm => cm.ID == (Guid)CurrentUserIdOperator.CurrentUserId(), 
            SecurityPermissionState.Allow);
            defaultRole.AddMemberPermissionFromLambda<ApplicationUser>(SecurityOperations.Write, 
            "StoredPassword", cm => cm.ID == (Guid)CurrentUserIdOperator.CurrentUserId(), 
            SecurityPermissionState.Allow);
            defaultRole.AddTypePermissionsRecursively<PermissionPolicyRole>(SecurityOperations.Read, 
            SecurityPermissionState.Deny);
            defaultRole.AddTypePermissionsRecursively<ModelDifference>(SecurityOperations.ReadWriteAccess, 
            SecurityPermissionState.Allow);
            defaultRole.AddTypePermissionsRecursively<ModelDifferenceAspect>(SecurityOperations.ReadWriteAccess, 
            SecurityPermissionState.Allow);
            defaultRole.AddTypePermissionsRecursively<ModelDifference>(SecurityOperations.Create, 
            SecurityPermissionState.Allow);
            defaultRole.AddTypePermissionsRecursively<ModelDifferenceAspect>(SecurityOperations.Create, 
            SecurityPermissionState.Allow);
        }
        return defaultRole;
    }
 }

Note

You can find more examples in the following topic: Security (Access Control & Authentication).

Optionally, you can configure your application to store user differences (individual user settings) in the database. Make the following changes in the MySolution.Blazor.Server\BlazorModule.cs (ASP.NET Core Blazor) and MySolution.Win\WinModule.cs (Windows Forms) files:

ASP.NET Core Blazor
Windows Forms

using DevExpress.ExpressApp;
using DevExpress.Persistent.BaseImpl;
// ...

public sealed class MySolutionBlazorModule : ModuleBase {
    // ...
    public override void Setup(XafApplication application) {
        base.Setup(application);
        application.CreateCustomUserModelDifferenceStore += Application_CreateCustomUserModelDifferenceStore;
    }
    private void Application_CreateCustomUserModelDifferenceStore(object sender, CreateCustomModelDifferenceStoreEventArgs e) {
        e.Store = new ModelDifferenceDbStore((XafApplication)sender, typeof(ModelDifference), false, "Blazor");
        e.Handled = true;
    }
}

using DevExpress.ExpressApp;
using DevExpress.Persistent.BaseImpl;
// ...

public sealed class MySolutionWinModule : ModuleBase {
    // ...
    public override void Setup(XafApplication application) {
        base.Setup(application);
        application.CreateCustomUserModelDifferenceStore += Application_CreateCustomUserModelDifferenceStore;
    }
    private void Application_CreateCustomUserModelDifferenceStore(object sender, CreateCustomModelDifferenceStoreEventArgs e) {
        e.Store = new ModelDifferenceDbStore((XafApplication)sender, typeof(ModelDifference), false, "Win");
        e.Handled = true;
    }
}

This way you can persist Detail View Layout changes made by individual users among other things. See the following help topic for more details: Persist Layout Customization For Individual Users.

Run the application. Log in under Admin. Leave the password field empty (you didn’t specify the password when you created this user). When you click the Log In button, the user’s credentials are authenticated and the application runs.
Select the My Details item in the navigation control and see the Detail View.

Create a Role in the UI

Administrators and other users with Role creation permission can create roles at runtime.

Select the Role item in the navigation control and click the New button. In the invoked Detail View, set the name and permissions for the new role.

ASP.NET Core Blazor

Windows Forms

With the Permission Policy property, you can assign the following permission policies:
- Deny all by default
- Read only all by default
- Allow all by default
For each operation, you can explicitly specify the Allow or Deny modifier, or leave it blank. If you don’t specify the modifier, the permission follows the role’s permission policy.

Create a User in the UI

Administrators and other users with User creation permission can create users at runtime.

Select the Application User item in the navigation control and click the New button. In the invoked Detail View, specify the User Name and assign one or more roles.

ASP.NET Core Blazor

Windows Forms

Tip
Deselect the Is Active checkbox if you need to deny user access to the application.

Controls

Tools

Controls and Extensions

Tools

Maintenance Mode

Controls

Tools

Controls and Extensions

Tools

Maintenance Mode

Implement Standard Authentication in Code

Create a Role in the UI

Create a User in the UI