//******************************************************************************************************//  HubClientBase.cs - Gbtc////  Copyright © 2016, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may not use this//  file except in compliance with the License. You may obtain a copy of the License at:////      http://opensource.org/licenses/MIT////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  08/16/2016 - Ritchie Carroll//       Generated original version of source code.////****************************************************************************************************** using System;using Microsoft.AspNet.SignalR.Hubs; namespace GSF.Web.Hubs{    /// <summary>    /// Represents a base class implementation for <see cref="IHubClient"/> implementations.    /// </summary>    /// <remarks>    /// This base class is useful for defining classes that should persist per SignalR session.    /// </remarks>    public abstract class HubClientBase : IHubClient    {        #region [ Members ]         // Fields        private dynamic m_clientScript;        private bool m_disposed;         #endregion         #region [ Properties ]         /// <summary>        /// Gets reference to SignalR hub client browser DOM functionality.        /// </summary>        /// <remarks>        /// This property can be used to call registered Javascript hub functions.        /// </remarks>        public dynamic ClientScript => m_clientScript ?? (m_clientScript = HubInstance?.Clients?.Client(ConnectionID));         /// <summary>        /// Gets or sets reference to SignalR hub instance.        /// </summary>        public IHub HubInstance        {            get;            set;        }         /// <summary>        /// Gets or sets the connection ID of the calling client.        /// </summary>        public string ConnectionID        {            get;            set;        }         /// <summary>        /// Gets or sets delegate to use to log status messages.        /// </summary>        public Action<string, UpdateType> LogStatusMessageFunction        {            get;            set;        }         /// <summary>        /// Gets or sets delegate to use to log exception messages.        /// </summary>        public Action<Exception> LogExceptionFunction        {            get;            set;        }         #endregion         #region [ Methods ]         /// <summary>        /// Releases all the resources used by the <see cref="HubClientBase"/> object.        /// </summary>        public void Dispose()        {            Dispose(true);            GC.SuppressFinalize(this);        }         /// <summary>        /// Releases the unmanaged resources used by the <see cref="HubClientBase"/> object and optionally releases the managed resources.        /// </summary>        /// <param name="disposing">true to release both managed and unmanaged resources; false to release only unmanaged resources.</param>        protected virtual void Dispose(bool disposing)        {            if (!m_disposed)            {                try                {                    if (disposing)                    {                        m_clientScript = null;                        HubInstance = null;                        LogStatusMessageFunction = null;                        LogExceptionFunction = null;                    }                }                finally                {                    m_disposed = true;  // Prevent duplicate dispose.                }            }        }         /// <summary>        /// Logs a status message to hub client and any provided log status message delegate.        /// </summary>        /// <param name="message">Message content to log.</param>        /// <param name="type">Type of message to log.</param>        /// <param name="logToClient">Determines if message should be logged to hub client.</param>        /// <remarks>        /// When <paramref name="logToClient"/> is <c>true</c>, function will        /// call "sendInfoMessage" Javascript hub client function if defined.        /// </remarks>        protected void LogStatusMessage(string message, UpdateType type = UpdateType.Information, bool logToClient = true)        {            try            {                // Send status message to hub client                if (logToClient)                    ClientScript?.sendInfoMessage(message, type == UpdateType.Information ? 2000 : -1);            }            catch (NullReferenceException)            {                // Attempting to access this property from self-created hub instance, i.e., a manually created                // instance instead of one created by SignalR, will cause a null-reference exception.            }             // Send status message to program host            LogStatusMessageFunction?.Invoke(message, type);        }         /// <summary>        /// Logs an exception to hub client and any provided log exception delegate.        /// </summary>        /// <param name="ex">Exception to log.</param>        /// <param name="logToClient">Determines if message should be logged to hub client.</param>        /// <remarks>        /// When <paramref name="logToClient"/> is <c>true</c>, function will        /// call "sendErrorMessage" Javascript hub client function if defined.        /// </remarks>        protected void LogException(Exception ex, bool logToClient = true)        {            try            {                // Send exception to hub client                if (logToClient)                    ClientScript?.sendErrorMessage(ex.Message, -1);            }            catch (NullReferenceException)            {                // Attempting to access this property from self-created hub instance, i.e., a manually created                // instance instead of one created by SignalR, will cause a null-reference exception.            }             // Send exception to program host            LogExceptionFunction?.Invoke(ex);        }         #endregion    }}