//******************************************************************************************************//  EmbeddedResourceProvider.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 a////      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://  ----------------------------------------------------------------------------------------------------//  08/04/2016 - J. Ritchie Carroll//       Generated original version of source code.////****************************************************************************************************** using System;using System.Collections;using System.IO;using System.Reflection;using System.Runtime.CompilerServices;using System.Web.Caching;using System.Web.Compilation;using System.Web.Hosting;using GSF.Reflection; namespace GSF.Web.Embedded{    /// <summary>    /// Represents a <see cref="VirtualPathProvider"/> that allows access to embedded resources.    /// </summary>    /// <remarks>    /// <para>    /// This provider responds to requests for embedded resources when the virtual path begins with an "@", e.g.,    /// http://localhost/@GSF.Web.Model.Scripts.gsf.web.client.js    /// </para>    /// <para>    /// To use, add the following to the Global.asax.cs Application_Start function:    /// <code>    ///     // Add additional virtual path provider to allow access to embedded resources    ///     EmbeddedResourceProvider.Register();    /// </code>    /// Then add the namespace paths to the embedded resources for which you need access to the Web.config &lt;system.webServer&gt; section:    /// <code>    /// &lt;system.webServer&gt;    ///   &lt;handlers&gt;    ///     &lt;!-- Add embedded resource handler for GSF script resources using slash delimiters --&gt;    ///     &lt;add name="EmbeddedResourceHandler-GSFScripts" path="@GSF/Web/Model/Scripts/*" verb="*" type="System.Web.StaticFileHandler" allowPathInfo="true" /&gt;    ///     &lt;!-- Add embedded resource handler for GSF view resources using slash delimiters --&gt;    ///     &lt;add name="EmbeddedResourceHandler-GSFViews" path="@GSF/Web/Model/Views/*" verb="*" type="System.Web.StaticFileHandler" allowPathInfo="true" /&gt;    ///     &lt;!-- Add embedded resource handler for GSF handler resources using slash delimiters --&gt;    ///     &lt;add name="EmbeddedResourceHandler-GSFHandlers" path="@GSF/Web/Model/Handlers/*" verb="*" type="System.Web.UI.SimpleHandlerFactory" allowPathInfo="true" /&gt;    ///     &lt;!-- Add embedded resource handler for fully qualified type names using dot delimiters (this should be defined last) --&gt;    ///     &lt;add name="EmbeddedResourceHandler-FQName" path="@*" verb="*" type="System.Web.StaticFileHandler" allowPathInfo="true" /&gt;    ///   &lt;/handlers&gt;    /// &lt;/system.webServer&gt;    /// </code>    /// </para>    /// </remarks>    public class EmbeddedResourceProvider : VirtualPathProvider    {        #region [ Members ]         // Nested Types         private class EmbeddedResource : VirtualFile        {            public EmbeddedResource(string virtualPath) : base(virtualPath)            {            }             public override Stream Open() => WebExtensions.OpenEmbeddedResourceStream(ParseResourceNameFromVirtualPath(VirtualPath));        }         #endregion         #region [ Methods ]         /// <summary>        /// Gets a value that indicates whether a file exists in the virtual file system.        /// </summary>        /// <returns>true if the file exists in the virtual file system; otherwise, false.</returns>        /// <param name="virtualPath">The path to the virtual file.</param>        /// <remarks>        /// Any virtual path that begins with an @ symbol is assumed to be an embedded resource where        /// the path represents the namespace hierarchy in either slash or dot notation.        /// </remarks>        public override bool FileExists(string virtualPath)        {            return WebExtensions.EmbeddedResourceExists(ParseResourceNameFromVirtualPath(virtualPath)) || Previous.FileExists(virtualPath);        }         /// <summary>        /// Gets a file from the virtual file system.        /// </summary>        /// <returns>An implementation of the <see cref="VirtualFile"/> class that represents a file in the virtual file system.</returns>        /// <param name="virtualPath">The path to the virtual file.</param>        public override VirtualFile GetFile(string virtualPath)        {            return WebExtensions.EmbeddedResourceExists(ParseResourceNameFromVirtualPath(virtualPath)) ? new EmbeddedResource(virtualPath) : Previous.GetFile(virtualPath);        }         /// <summary>        /// Gets a value that indicates whether a directory exists in the virtual file system.        /// </summary>        /// <returns>true if the directory exists in the virtual file system; otherwise, false.</returns>        /// <param name="virtualDir">The path to the virtual directory.</param>        public override bool DirectoryExists(string virtualDir)        {            // Assume any given resource path exists - GetFile will validate full namespace for resource            return IsEmbeddedResource(virtualDir) || Previous.DirectoryExists(virtualDir);        }         /// <summary>        /// Gets a virtual directory from the virtual file system.        /// </summary>        /// <returns>A descendant of the <see cref="VirtualDirectory" /> class that represents a directory in the virtual file system.</returns>        /// <param name="virtualDir">The path to the virtual directory.</param>        public override VirtualDirectory GetDirectory(string virtualDir)        {            return Previous.GetDirectory(virtualDir);        }         /// <summary>        /// Creates a cache dependency based on the specified virtual paths.        /// </summary>        /// <returns>A <see cref="CacheDependency" /> object for the specified virtual resources.</returns>        /// <param name="virtualPath">The path to the primary virtual resource.</param>        /// <param name="virtualPathDependencies">An array of paths to other resources required by the primary virtual resource.</param>        /// <param name="utcStart">The UTC time at which the virtual resources were read.</param>        public override CacheDependency GetCacheDependency(string virtualPath, IEnumerable virtualPathDependencies, DateTime utcStart)        {            return IsEmbeddedResource(virtualPath) ? null : Previous.GetCacheDependency(virtualPath, virtualPathDependencies, utcStart);        }         #endregion         #region [ Static ]         /// <summary>        /// Registers the <see cref="EmbeddedResourceProvider"/> within a <see cref="HostingEnvironment"/>.        /// </summary>        /// <remarks>        /// This function will properly register the <see cref="EmbeddedResourceProvider"/> even when being run from        /// within a pre-compiled web application.        /// </remarks>        public static void Register()        {            if (BuildManager.IsPrecompiledApp)            {                // HACK: Call internal registration function for virtual path provider in pre-compiled web application                Type hostingEnvironment = AssemblyInfo.FindType("System.Web.Hosting.HostingEnvironment");                 if ((object)hostingEnvironment == null)                    throw new InvalidOperationException("Failed to register EmbeddedResourceProvider: could not find type \"System.Web.Hosting.HostingEnvironment\".");                 MethodInfo internalRegisterVirtualPathProvider = hostingEnvironment.GetMethod("RegisterVirtualPathProviderInternal", BindingFlags.NonPublic | BindingFlags.Static);                 if ((object)internalRegisterVirtualPathProvider == null)                    throw new InvalidOperationException("Failed to register EmbeddedResourceProvider: could not find internal static method \"System.Web.Hosting.HostingEnvironment.RegisterVirtualPathProviderInternal()\".");                 internalRegisterVirtualPathProvider.Invoke(null, new object[] { new EmbeddedResourceProvider() });            }            else            {                HostingEnvironment.RegisterVirtualPathProvider(new EmbeddedResourceProvider());            }        }         [MethodImpl(MethodImplOptions.AggressiveInlining)]        private static string ParseResourceNameFromVirtualPath(string virtualPath)        {            return virtualPath.Substring(virtualPath.IndexOf('@') + 1).Replace('/', '.');        }         [MethodImpl(MethodImplOptions.AggressiveInlining)]        private static bool IsEmbeddedResource(string virtualPath)        {            return virtualPath.StartsWith("@") || virtualPath.Contains("/@");        }         #endregion    }}