Table of Contents
Prerequisites
.Netcore 3.x
Nopcommerce 3.x
come from:
//Contributor: Umbraco (http://www.umbraco.com). Thanks a lot!
//SEE THIS POST for full details of what this does - http://shazwazza.com/post/Developing-a-plugin-framework-in-ASPNET-with-medium-trust.aspx
Code
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Threading;
using System.Web;
using Nop.Core.ComponentModel;
using Microsoft.AspNetCore.Mvc.ApplicationParts;
//Contributor: Umbraco (http://www.umbraco.com). Thanks a lot!
//SEE THIS POST for full details of what this does - http://shazwazza.com/post/Developing-a-plugin-framework-in-ASPNET-with-medium-trust.aspx
namespace Nop.Core.Plugins
{
/// <summary>
/// Sets the application up for the plugin referencing
/// </summary>
public class PluginManager
{
#region Const
private const string InstalledPluginsFilePath = "~/App_Data/InstalledPlugins.txt";
private const string PluginsPath = "~/Plugins";
private const string ShadowCopyPath = "~/Plugins/bin";
#endregion
#region Fields
private static readonly ReaderWriterLockSlim Locker = new ReaderWriterLockSlim();
private static DirectoryInfo _shadowCopyFolder;
#endregion
#region Methods
/// <summary>
/// Returns a collection of all referenced plugin assemblies that have been shadow copied
/// </summary>
public static IEnumerable<PluginDescriptor> ReferencedPlugins { get; set; }
/// <summary>
/// Returns a collection of all plugin which are not compatible with the current version
/// </summary>
public static IEnumerable<string> IncompatiblePlugins { get; set; }
/// <summary>
/// Initialize
/// </summary>
public static void Initialize(ApplicationPartManager applicationPartManager)
{
using (new WriteLockDisposable(Locker))
{
// TODO: Add verbose exception handling / raising here since this is happening on app startup and could
// prevent app from starting altogether
var pluginFolder = new DirectoryInfo(CommonHelper.MapPath(PluginsPath));
_shadowCopyFolder = new DirectoryInfo(CommonHelper.MapPath(ShadowCopyPath));
var referencedPlugins = new List<PluginDescriptor>();
var incompatiblePlugins = new List<string>();
try
{
var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath());
Debug.WriteLine("Creating shadow copy folder and querying for dlls");
//ensure folders are created
Directory.CreateDirectory(pluginFolder.FullName);
Directory.CreateDirectory(_shadowCopyFolder.FullName);
//get list of all files in bin
var binFiles = _shadowCopyFolder.GetFiles("*", SearchOption.AllDirectories);
//load description files
foreach (var dfd in GetDescriptionFilesAndDescriptors(pluginFolder))
{
var descriptionFile = dfd.Key;
var pluginDescriptor = dfd.Value;
//ensure that version of plugin is valid
if (!pluginDescriptor.SupportedVersions.Contains(NopVersion.CurrentVersion, StringComparer.InvariantCultureIgnoreCase))
{
incompatiblePlugins.Add(pluginDescriptor.SystemName);
continue;
}
//some validation
if (String.IsNullOrWhiteSpace(pluginDescriptor.SystemName))
throw new Exception(string.Format("A plugin '{0}' has no system name. Try assigning the plugin a unique name and recompiling.", descriptionFile.FullName));
if (referencedPlugins.Contains(pluginDescriptor))
throw new Exception(string.Format("A plugin with '{0}' system name is already defined", pluginDescriptor.SystemName));
//set 'Installed' property
pluginDescriptor.Installed = installedPluginSystemNames
.FirstOrDefault(x => x.Equals(pluginDescriptor.SystemName, StringComparison.InvariantCultureIgnoreCase)) != null;
try
{
if (descriptionFile.Directory == null)
throw new Exception(string.Format("Directory cannot be resolved for '{0}' description file", descriptionFile.Name));
//get list of all DLLs in plugins (not in bin!)
var pluginFiles = descriptionFile.Directory.GetFiles("*.dll", SearchOption.AllDirectories)
//just make sure we're not registering shadow copied plugins
.Where(x => !binFiles.Select(q => q.FullName).Contains(x.FullName))
.Where(x => IsPackagePluginFolder(x.Directory))
.ToList();
//other plugin description info
var mainPluginFile = pluginFiles
.FirstOrDefault(x => x.Name.Equals(pluginDescriptor.PluginFileName, StringComparison.InvariantCultureIgnoreCase));
pluginDescriptor.OriginalAssemblyFile = mainPluginFile;
//shadow copy main plugin file
pluginDescriptor.ReferencedAssembly = PerformFileDeploy(mainPluginFile, applicationPartManager);
//load all other referenced assemblies now
foreach (var plugin in pluginFiles
.Where(x => !x.Name.Equals(mainPluginFile.Name, StringComparison.InvariantCultureIgnoreCase))
.Where(x => !IsAlreadyLoaded(x)))
PerformFileDeploy(plugin, applicationPartManager);
//init plugin type (only one plugin per assembly is allowed)
foreach (var t in pluginDescriptor.ReferencedAssembly.GetTypes())
if (typeof(IPlugin).IsAssignableFrom(t))
if (!t.IsInterface)
if (t.IsClass && !t.IsAbstract)
{
pluginDescriptor.PluginType = t;
break;
}
referencedPlugins.Add(pluginDescriptor);
}
catch (ReflectionTypeLoadException ex)
{
//add a plugin name. this way we can easily identify a problematic plugin
var msg = string.Format("Plugin '{0}'. ", pluginDescriptor.FriendlyName);
foreach (var e in ex.LoaderExceptions)
msg += e.Message + Environment.NewLine;
var fail = new Exception(msg, ex);
throw fail;
}
catch (Exception ex)
{
//add a plugin name. this way we can easily identify a problematic plugin
var msg = string.Format("Plugin '{0}'. {1}", pluginDescriptor.FriendlyName, ex.Message);
var fail = new Exception(msg, ex);
throw fail;
}
}
}
catch (Exception ex)
{
var msg = string.Empty;
for (var e = ex; e != null; e = e.InnerException)
msg += e.Message + Environment.NewLine;
var fail = new Exception(msg, ex);
throw fail;
}
ReferencedPlugins = referencedPlugins;
IncompatiblePlugins = incompatiblePlugins;
}
}
/// <summary>
/// Mark plugin as installed
/// </summary>
/// <param name="systemName">Plugin system name</param>
public static void MarkPluginAsInstalled(string systemName)
{
if (String.IsNullOrEmpty(systemName))
throw new ArgumentNullException("systemName");
var filePath = CommonHelper.MapPath(InstalledPluginsFilePath);
if (!File.Exists(filePath))
using (File.Create(filePath))
{
//we use 'using' to close the file after it's created
}
var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath());
bool alreadyMarkedAsInstalled = installedPluginSystemNames
.FirstOrDefault(x => x.Equals(systemName, StringComparison.InvariantCultureIgnoreCase)) != null;
if (!alreadyMarkedAsInstalled)
installedPluginSystemNames.Add(systemName);
PluginFileParser.SaveInstalledPluginsFile(installedPluginSystemNames,filePath);
}
/// <summary>
/// Mark plugin as uninstalled
/// </summary>
/// <param name="systemName">Plugin system name</param>
public static void MarkPluginAsUninstalled(string systemName)
{
if (String.IsNullOrEmpty(systemName))
throw new ArgumentNullException("systemName");
var filePath = CommonHelper.MapPath(InstalledPluginsFilePath);
if (!File.Exists(filePath))
using (File.Create(filePath))
{
//we use 'using' to close the file after it's created
}
var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath());
bool alreadyMarkedAsInstalled = installedPluginSystemNames
.FirstOrDefault(x => x.Equals(systemName, StringComparison.InvariantCultureIgnoreCase)) != null;
if (alreadyMarkedAsInstalled)
installedPluginSystemNames.Remove(systemName);
PluginFileParser.SaveInstalledPluginsFile(installedPluginSystemNames,filePath);
}
/// <summary>
/// Mark plugin as uninstalled
/// </summary>
public static void MarkAllPluginsAsUninstalled()
{
var filePath = CommonHelper.MapPath(InstalledPluginsFilePath);
if (File.Exists(filePath))
File.Delete(filePath);
}
/// <summary>
/// Find a plugin descriptor by some type which is located into the same assembly as plugin
/// </summary>
/// <param name="typeInAssembly">Type</param>
/// <returns>Plugin descriptor if exists; otherwise null</returns>
public static PluginDescriptor FindPlugin(Type typeInAssembly)
{
if (typeInAssembly == null)
throw new ArgumentNullException("typeInAssembly");
if (ReferencedPlugins == null)
return null;
return ReferencedPlugins.FirstOrDefault(plugin => plugin.ReferencedAssembly != null
&& plugin.ReferencedAssembly.FullName.Equals(typeInAssembly.Assembly.FullName, StringComparison.InvariantCultureIgnoreCase));
}
#endregion
#region Utilities
/// <summary>
/// Get description files
/// </summary>
/// <param name="pluginFolder">Plugin directory info</param>
/// <returns>Original and parsed description files</returns>
private static IEnumerable<KeyValuePair<FileInfo, PluginDescriptor>> GetDescriptionFilesAndDescriptors(DirectoryInfo pluginFolder)
{
if (pluginFolder == null)
throw new ArgumentNullException("pluginFolder");
//create list (<file info, parsed plugin descritor>)
var result = new List<KeyValuePair<FileInfo, PluginDescriptor>>();
//add display order and path to list
foreach (var descriptionFile in pluginFolder.GetFiles("Description.txt", SearchOption.AllDirectories))
{
if (!IsPackagePluginFolder(descriptionFile.Directory))
continue;
//parse file
var pluginDescriptor = PluginFileParser.ParsePluginDescriptionFile(descriptionFile.FullName);
//populate list
result.Add(new KeyValuePair<FileInfo, PluginDescriptor>(descriptionFile, pluginDescriptor));
}
//sort list by display order. NOTE: Lowest DisplayOrder will be first i.e 0 , 1, 1, 1, 5, 10
//it's required: http://www.nopcommerce.com/boards/t/17455/load-plugins-based-on-their-displayorder-on-startup.aspx
result.Sort((firstPair, nextPair) => firstPair.Value.DisplayOrder.CompareTo(nextPair.Value.DisplayOrder));
return result;
}
/// <summary>
/// Indicates whether assembly file is already loaded
/// </summary>
/// <param name="fileInfo">File info</param>
/// <returns>Result</returns>
private static bool IsAlreadyLoaded(FileInfo fileInfo)
{
//compare full assembly name
//var fileAssemblyName = AssemblyName.GetAssemblyName(fileInfo.FullName);
//foreach (var a in AppDomain.CurrentDomain.GetAssemblies())
//{
// if (a.FullName.Equals(fileAssemblyName.FullName, StringComparison.InvariantCultureIgnoreCase))
// return true;
//}
//return false;
//do not compare the full assembly name, just filename
try
{
string fileNameWithoutExt = Path.GetFileNameWithoutExtension(fileInfo.FullName);
if (string.IsNullOrEmpty(fileNameWithoutExt))
throw new Exception(string.Format("Cannot get file extension for {0}", fileInfo.Name));
foreach (var a in AppDomain.CurrentDomain.GetAssemblies())
{
string assemblyName = a.FullName.Split(new[] { ',' }).FirstOrDefault();
if (fileNameWithoutExt.Equals(assemblyName, StringComparison.InvariantCultureIgnoreCase))
return true;
}
}
catch (Exception exc)
{
Debug.WriteLine("Cannot validate whether an assembly is already loaded. " + exc);
}
return false;
}
/// <summary>
/// Perform file deply
/// </summary>
/// <param name="plug">Plugin file info</param>
/// <param name="applicationPartManager">Application part manager</param>
/// <returns>Assembly</returns>
private static Assembly PerformFileDeploy(FileInfo plug, ApplicationPartManager applicationPartManager)
{
if (plug.Directory == null || plug.Directory.Parent == null)
throw new InvalidOperationException("The plugin directory for the " + plug.Name + " file exists in a folder outside of the allowed nopCommerce folder hierarchy");
//now asp.net core doesn't init DynamicDirectory in AppContext, that's why we commented the following code
//FileInfo shadowCopiedPlug;
//if (CommonHelper.GetTrustLevel() != AspNetHostingPermissionLevel.Unrestricted || string.IsNullOrEmpty(AppDomain.CurrentDomain.DynamicDirectory))
//{
// //all plugins will need to be copied to ~/Plugins/bin/
// //this is absolutely required because all of this relies on probingPaths being set statically in the web.config
// //were running in med trust, so copy to custom bin folder
// var shadowCopyPlugFolder = Directory.CreateDirectory(_shadowCopyFolder.FullName);
// shadowCopiedPlug = InitializeMediumTrust(plug, shadowCopyPlugFolder);
//}
//else
//{
// var directory = AppDomain.CurrentDomain.DynamicDirectory;
// Debug.WriteLine(plug.FullName + " to " + directory);
// //were running in full trust so copy to standard dynamic folder
// shadowCopiedPlug = InitializeFullTrust(plug, new DirectoryInfo(directory));
//}
//but in order to avoid possible issues we still copy libraries into ~/Plugins/bin/ directory
var shadowCopyPlugFolder = Directory.CreateDirectory(_shadowCopyFolder.FullName);
var shadowCopiedPlug = InitializeMediumTrust(plug, shadowCopyPlugFolder);
//we can now register the plugin definition
var shadowCopiedAssembly = Assembly.Load(AssemblyName.GetAssemblyName(shadowCopiedPlug.FullName));
Debug.WriteLine("Adding to ApplicationParts: '{0}'", shadowCopiedAssembly.FullName);
applicationPartManager.ApplicationParts.Add(new AssemblyPart(shadowCopiedAssembly));
return shadowCopiedAssembly;
}
/// <summary>
/// Used to initialize plugins when running in Full Trust
/// </summary>
/// <param name="plug"></param>
/// <param name="shadowCopyPlugFolder"></param>
/// <returns></returns>
private static FileInfo InitializeFullTrust(FileInfo plug, DirectoryInfo shadowCopyPlugFolder)
{
var shadowCopiedPlug = new FileInfo(Path.Combine(shadowCopyPlugFolder.FullName, plug.Name));
try
{
File.Copy(plug.FullName, shadowCopiedPlug.FullName, true);
}
catch (IOException)
{
Debug.WriteLine(shadowCopiedPlug.FullName + " is locked, attempting to rename");
//this occurs when the files are locked,
//for some reason devenv locks plugin files some times and for another crazy reason you are allowed to rename them
//which releases the lock, so that it what we are doing here, once it's renamed, we can re-shadow copy
try
{
var oldFile = shadowCopiedPlug.FullName + Guid.NewGuid().ToString("N") + ".old";
File.Move(shadowCopiedPlug.FullName, oldFile);
}
catch (IOException exc)
{
throw new IOException(shadowCopiedPlug.FullName + " rename failed, cannot initialize plugin", exc);
}
//ok, we've made it this far, now retry the shadow copy
File.Copy(plug.FullName, shadowCopiedPlug.FullName, true);
}
return shadowCopiedPlug;
}
/// <summary>
/// Used to initialize plugins when running in Medium Trust
/// </summary>
/// <param name="plug"></param>
/// <param name="shadowCopyPlugFolder"></param>
/// <returns></returns>
private static FileInfo InitializeMediumTrust(FileInfo plug, DirectoryInfo shadowCopyPlugFolder)
{
var shouldCopy = true;
var shadowCopiedPlug = new FileInfo(Path.Combine(shadowCopyPlugFolder.FullName, plug.Name));
//check if a shadow copied file already exists and if it does, check if it's updated, if not don't copy
if (shadowCopiedPlug.Exists)
{
//it's better to use LastWriteTimeUTC, but not all file systems have this property
//maybe it is better to compare file hash?
var areFilesIdentical = shadowCopiedPlug.CreationTimeUtc.Ticks >= plug.CreationTimeUtc.Ticks;
if (areFilesIdentical)
{
Debug.WriteLine("Not copying; files appear identical: '{0}'", shadowCopiedPlug.Name);
shouldCopy = false;
}
else
{
//delete an existing file
//More info: http://www.nopcommerce.com/boards/t/11511/access-error-nopplugindiscountrulesbillingcountrydll.aspx?p=4#60838
Debug.WriteLine("New plugin found; Deleting the old file: '{0}'", shadowCopiedPlug.Name);
File.Delete(shadowCopiedPlug.FullName);
}
}
if (shouldCopy)
{
try
{
File.Copy(plug.FullName, shadowCopiedPlug.FullName, true);
}
catch (IOException)
{
Debug.WriteLine(shadowCopiedPlug.FullName + " is locked, attempting to rename");
//this occurs when the files are locked,
//for some reason devenv locks plugin files some times and for another crazy reason you are allowed to rename them
//which releases the lock, so that it what we are doing here, once it's renamed, we can re-shadow copy
try
{
var oldFile = shadowCopiedPlug.FullName + Guid.NewGuid().ToString("N") + ".old";
File.Move(shadowCopiedPlug.FullName, oldFile);
}
catch (IOException exc)
{
throw new IOException(shadowCopiedPlug.FullName + " rename failed, cannot initialize plugin", exc);
}
//ok, we've made it this far, now retry the shadow copy
File.Copy(plug.FullName, shadowCopiedPlug.FullName, true);
}
}
return shadowCopiedPlug;
}
/// <summary>
/// Determines if the folder is a bin plugin folder for a package
/// </summary>
/// <param name="folder"></param>
/// <returns></returns>
private static bool IsPackagePluginFolder(DirectoryInfo folder)
{
if (folder == null) return false;
if (folder.Parent == null) return false;
if (!folder.Parent.Name.Equals("Plugins", StringComparison.InvariantCultureIgnoreCase)) return false;
return true;
}
/// <summary>
/// Gets the full path of InstalledPlugins.txt file
/// </summary>
/// <returns></returns>
private static string GetInstalledPluginsFilePath()
{
return CommonHelper.MapPath(InstalledPluginsFilePath);
}
#endregion
}
}