add support for XWebinarGroupEntity and it's InMemory Repository and also Register it's required Services and usage in WebinarHub ...

DI/XDIHelperExtension.cs

@@ -1,12 +1,16 @@
 using System;
 using Microsoft.Extensions.DependencyInjection;
 using xCommons.Extensions;
+using xDataService.Interfaces;
+using xDataService.Providers;
 using xExceptions.Constants;
 using xWebinarService.Interfaces;
 using xWebinarService.Interfaces.Entities;
+using xWebinarService.Models.Entities;
 using xWebinarService.Providers;
 
-namespace xWebinarService.DI {
+namespace xWebinarService.DI
+{
     public static class XDIHelperExtension
     {
         /// <summary>
@@ -89,6 +93,11 @@ namespace xWebinarService.DI {
                 throw exception;
             }
 
+            //
+            // Register Webinar Group In Memory Repository ...
+            services.AddSingleton<IXKeyGenerator<XWebinarGroupEntity, Guid>, XGuidKeyGenerator<XWebinarGroupEntity>>();
+            services.Add(new ServiceDescriptor(typeof(IXWebinarGroupStore), typeof(XWebinarGroupStore), ServiceLifetime.Singleton));
+
             //
             // Register Resource Providers ...
             services.Add(new ServiceDescriptor(typeof(IXWebinarTitleResourceProvider), typeof(XWebinarTitleResourceProvider), lifeTime));

Hubs/XWebinarHub.cs

@@ -1,18 +1,18 @@
 using System;
-using System.Text;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
 using System.Threading.Tasks;
-using System.Xml.Linq;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.SignalR;
 using Microsoft.Extensions.Logging;
 using xCommons.Extensions;
 using xExceptions.Constants;
-using xIdentityModels.Models;
 using xPushService.Base;
 using xPushService.Extensions;
 using xWebinarService.Constants;
-using xWebinarService.Models.Dtos;
 using xWebinarService.Interfaces;
+using xWebinarService.Models.Entities;
 
 namespace xWebinarService.Hubs
 {
@@ -21,16 +21,19 @@ namespace xWebinarService.Hubs
         //
         #region Props ...
         public readonly IXWebinarProvider webinarProvider;
+        private readonly IXWebinarGroupStore webinarGroupStore;
         #endregion
 
         //
         #region Constructor ...
         public XWebinarHub(
             ILogger<XWebinarHub> logger,
-            IXWebinarProvider webinarProvider
+            IXWebinarProvider webinarProvider,
+            IXWebinarGroupStore webinarGroupStore
         ) : base(logger)
         {
             this.webinarProvider = webinarProvider;
+            this.webinarGroupStore = webinarGroupStore;
         }
         #endregion
 
@@ -107,6 +110,35 @@ namespace xWebinarService.Hubs
                 //
                 // Create a Group and Put User on it ...
                 await Groups.AddToGroupAsync(connectionId, webinarId.ToString());
+
+                //
+                // Check Exists or not ...
+                var connection = new XHubConnectionDto
+                {
+                    UserId = userInfo.UserId,
+                    ConnectionId = connectionId,
+                    Username = userInfo.UserName,
+                };
+                var groupEntity = await webinarGroupStore.FindOneAsync(x => x.WebinarId == webinarId);
+                if (!groupEntity.IsNullOrDefault())
+                {
+                    //
+                    // Update ...
+                    groupEntity.Connections.Clear();
+                    groupEntity.Connections.Add(connection);
+                    await webinarGroupStore.UpdateAsync(groupEntity.Id, groupEntity);
+                }
+                else
+                {
+                    //
+                    // Add ...
+                    groupEntity = new XWebinarGroupEntity
+                    {
+                        WebinarId = webinarId
+                    };
+                    groupEntity.Connections.Add(connection);
+                    await webinarGroupStore.AddAsync(groupEntity);
+                }
             }
             catch { }
         }
@@ -183,6 +215,14 @@ namespace xWebinarService.Hubs
                 var webinarName = webinarId.ToString();
                 await Clients.OthersInGroup(webinarName).SendAsync(XWebinarHubAction.WebinarClosed.ToString());
                 await Groups.RemoveFromGroupAsync(connectionId, webinarName);
+
+                //
+                // Check Exists or not ...
+                var groupEntity = await webinarGroupStore.FindOneAsync(x => x.WebinarId == webinarId);
+                if (!groupEntity.IsNullOrDefault())
+                {
+                    await webinarGroupStore.RemoveAsync(groupEntity.Id);
+                }
             }
             catch { }
         }
@@ -266,6 +306,33 @@ namespace xWebinarService.Hubs
                     userInfo.UserId,
                     userInfo.UserName
                 );
+
+                //
+                // Check Exists or not ...
+                var connection = new XHubConnectionDto
+                {
+                    UserId = userInfo.UserId,
+                    ConnectionId = connectionId,
+                    Username = userInfo.UserName,
+                };
+                var groupEntity = await webinarGroupStore.FindOneAsync(x => x.WebinarId == webinarId);
+                if (!groupEntity.IsNullOrDefault())
+                {
+                    //
+                    // Check Current User ID Exists ...
+                    var userConnection = groupEntity.Connections.FirstOrDefault(c => c.UserId == userInfo.UserId);
+                    if (!userConnection.IsNullOrDefault())
+                    {
+                        userConnection.ConnectionId = connectionId;
+                    }
+                    else
+                    {
+                        groupEntity.Connections.Add(connection);
+                    }
+
+                    //
+                    await webinarGroupStore.UpdateAsync(groupEntity.Id, groupEntity);
+                }
             }
             catch
             { }
@@ -350,11 +417,65 @@ namespace xWebinarService.Hubs
                     userInfo.UserId,
                     userInfo.UserName
                 );
+
+                //
+                // Check Exists or not ...
+                var groupEntity = await webinarGroupStore.FindOneAsync(x => x.WebinarId == webinarId);
+                if (!groupEntity.IsNullOrDefault())
+                {
+                    //
+                    // Check Current User ID Exists ...
+                    var userConnection = groupEntity.Connections.FirstOrDefault(c => c.ConnectionId == connectionId);
+                    if (!userConnection.IsNullOrDefault())
+                    {
+                        groupEntity.Connections.Remove(userConnection);
+                    }
+
+                    //
+                    await webinarGroupStore.UpdateAsync(groupEntity.Id, groupEntity);
+                }
             }
             catch
             { }
         }
 
+        /// <summary>
+        /// Return a Collection of Webinars Visitors ...
+        /// </summary>
+        /// <param name="webinarId"></param>
+        /// <returns></returns>
+        [Authorize]
+        public async Task<IEnumerable<XHubConnectionDto>> WebinarVisitors(Guid webinarId)
+        {
+            //
+            var result = new List<XHubConnectionDto>();
+
+            //
+            // Reading and Validate Requirements ...
+            var userInfo = Context.GetUserInfo();
+            var connectionId = Context.ConnectionId;
+
+
+            //
+            // Check Group Exists ...
+            var groupEntity = await webinarGroupStore.FindOneAsync(x => x.WebinarId == webinarId);
+            if (!groupEntity.IsNullOrDefault())
+            {
+                //
+                // Validate Requester is a Viewer ...
+                var connection = groupEntity.Connections.FirstOrDefault(c => c.ConnectionId == connectionId ||
+                    c.UserId == userInfo.UserId
+                );
+                if (!connection.IsNullOrDefault())
+                {
+                    result = groupEntity.Connections;
+                }
+            }
+
+            //
+            return result;
+        }
+
         /// <summary>
         /// Send a Message to Specified Webinar ...
         /// </summary>

Interfaces/IXWebinarGroupStore.cs

@@ -0,0 +1,11 @@
+using System;
+using xDataService.Interfaces;
+using xWebinarService.Models.Entities;
+
+namespace xWebinarService.Interfaces
+{
+    public interface IXWebinarGroupStore : IXBaseRepository<XWebinarGroupEntity, Guid>
+    {
+        
+    }
+}

Models/Entities/XWebinarGroupEntity.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using xModels.Base;
+using xPushService.Base;
+
+namespace xWebinarService.Models.Entities
+{
+    public class XWebinarGroupEntity : XBaseGuidIDEntity
+    {
+       public Guid WebinarId { get; set; } 
+       public List<XHubConnectionDto> Connections { get; set; } = new List<XHubConnectionDto>();
+    }
+}

Providers/XWebinarGroupStore.cs

@@ -0,0 +1,20 @@
+using System;
+using xDataService.Configuration;
+using xDataService.InMemRepositories;
+using xDataService.Interfaces;
+using xWebinarService.Interfaces;
+using xWebinarService.Models.Entities;
+
+namespace xWebinarService.Providers
+{
+    public class XWebinarGroupStore : XBaseInMemoryRepositoy<XWebinarGroupEntity, Guid>, IXWebinarGroupStore
+    {
+        public XWebinarGroupStore(
+            XDataServiceConfiguration configuration,
+            IXKeyGenerator<XWebinarGroupEntity, Guid> keyGenerator = null,
+            IXBaseRepositoryEvents<XWebinarGroupEntity> baseRepositoryEvents = null
+        ) : base(configuration, keyGenerator, baseRepositoryEvents)
+        {
+        }
+    }
+}

xWebinarService.csproj

@@ -22,7 +22,7 @@
 
   <!-- Local Modules -->
   <ItemGroup>
-    <PackageReference Include="xDashboard.xDataService" Version="1.0.0" />
+    <!-- <PackageReference Include="xDashboard.xDataService" Version="1.0.0" /> -->
     <PackageReference Include="xDashboard.xStringService" Version="1.0.0" />
     <!-- <PackageReference Include="xDashboard.xIdentityService" Version="1.0.0" /> -->
   </ItemGroup>
@@ -31,8 +31,8 @@
   <ItemGroup>
     <ProjectReference Include="../xPushService/xPushService.csproj" />
     <ProjectReference Include="../xIdentityService/xIdentityService.csproj" /> 
-    <!-- 
     <ProjectReference Include="../xDataService/xDataService.csproj" />
+    <!-- 
     <ProjectReference Include="../xStringService/xStringService.csproj" />
     -->
   </ItemGroup>