ModuleLoader.cs

#region License
// 
// Author: Nate Kohari <nate@enkari.com>
// Copyright (c) 2007-2010, Enkari, Ltd.
// 
// Dual-licensed under the Apache License, Version 2.0, and the Microsoft Public License (Ms-PL).
// See the file LICENSE.txt for details.
// 
#endregion
#if !NO_ASSEMBLY_SCANNING
#region Using Directives
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
#if !NO_WEB
using System.Text.RegularExpressions;
using System.Web;
#endif
using Ninject.Components;
using Ninject.Infrastructure;
#endregion

namespace Ninject.Modules
{
	/// <summary>
	/// Automatically finds and loads modules from assemblies.
	/// </summary>
	public class ModuleLoader : NinjectComponent, IModuleLoader
	{
		/// <summary>
		/// Gets or sets the kernel into which modules will be loaded.
		/// </summary>
		public IKernel Kernel { get; private set; }

		/// <summary>
		/// Initializes a new instance of the <see cref="ModuleLoader"/> class.
		/// </summary>
		/// <param name="kernel">The kernel into which modules will be loaded.</param>
		public ModuleLoader(IKernel kernel)
		{
			Ensure.ArgumentNotNull(kernel, "kernel");
			Kernel = kernel;
		}

		/// <summary>
		/// Loads any modules found in the files that match the specified patterns.
		/// </summary>
		/// <param name="patterns">The patterns to search.</param>
		public void LoadModules(IEnumerable<string> patterns)
		{
			var plugins = Kernel.Components.GetAll<IModuleLoaderPlugin>();

			var fileGroups = patterns
				.SelectMany(pattern => GetFilesMatchingPattern(pattern))
				.GroupBy(filename => Path.GetExtension(filename).ToLowerInvariant());

			foreach (var fileGroup in fileGroups)
			{
				string extension = fileGroup.Key;
				IModuleLoaderPlugin plugin = plugins.Where(p => p.SupportedExtensions.Contains(extension)).FirstOrDefault();

				if (plugin != null)
					plugin.LoadModules(fileGroup);
			}
		}

        private static IEnumerable<string> GetFilesMatchingPattern(string pattern)
        {
            foreach (var path in NormalizePaths(Path.GetDirectoryName(pattern)))
            {
                string glob = Path.GetFileName(pattern);
                foreach (var file in Directory.GetFiles(path, glob))
                {
                    yield return file;
                }
            }
        }

	    private static IEnumerable<string> NormalizePaths(string path)
		{
			if (!Path.IsPathRooted(path))
			{
			    foreach (var baseDirectory in GetBaseDirectories().ToList())
			    {
                    yield return Path.Combine(baseDirectory, path);
			    }
                yield break;
			}

            yield return Path.GetFullPath(path);
		}

        private static IEnumerable<string> GetBaseDirectories()
        {
            string baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
            string searchPath = AppDomain.CurrentDomain.RelativeSearchPath;

            if (!string.IsNullOrEmpty(searchPath))
            {
                var paths = searchPath.Split(new[] {Path.PathSeparator}, StringSplitOptions.RemoveEmptyEntries);
                foreach (var path in paths)
                {
                    yield return Path.Combine(baseDirectory, path);
                }
                yield break;
            }
            yield return baseDirectory;
        }
	}
}
#endif //!NO_ASSEMBLY_SCANNING