mcs/class/System.Web.Mvc/System.Web.Mvc/VirtualPathProviderViewEngine.cs

   1 /* ****************************************************************************\r
   2  *\r
   3  * Copyright (c) Microsoft Corporation. All rights reserved.\r
   4  *\r
   5  * This software is subject to the Microsoft Public License (Ms-PL). \r
   6  * A copy of the license can be found in the license.htm file included \r
   7  * in this distribution.\r
   8  *\r
   9  * You must not remove this notice, or any other, from this software.\r
  10  *\r
  11  * ***************************************************************************/\r
  12 \r
  13 namespace System.Web.Mvc {\r
  14     using System;\r
  15     using System.Diagnostics.CodeAnalysis;\r
  16     using System.Globalization;\r
  17     using System.Linq;\r
  18     using System.Web;\r
  19     using System.Web.Hosting;\r
  20     using System.Web.Mvc.Resources;\r
  21 \r
  22     public abstract class VirtualPathProviderViewEngine : IViewEngine {\r
  23         // format is ":ViewCacheEntry:{cacheType}:{prefix}:{name}:{controllerName}:"\r
  24         private const string _cacheKeyFormat = ":ViewCacheEntry:{0}:{1}:{2}:{3}:";\r
  25         private const string _cacheKeyPrefix_Master = "Master";\r
  26         private const string _cacheKeyPrefix_Partial = "Partial";\r
  27         private const string _cacheKeyPrefix_View = "View";\r
  28         private static readonly string[] _emptyLocations = new string[0];\r
  29 \r
  30         private VirtualPathProvider _vpp;\r
  31 \r
  32         [SuppressMessage("Microsoft.Performance", "CA1819:PropertiesShouldNotReturnArrays")]\r
  33         public string[] MasterLocationFormats {\r
  34             get;\r
  35             set;\r
  36         }\r
  37 \r
  38         [SuppressMessage("Microsoft.Performance", "CA1819:PropertiesShouldNotReturnArrays")]\r
  39         public string[] PartialViewLocationFormats {\r
  40             get;\r
  41             set;\r
  42         }\r
  43 \r
  44         public IViewLocationCache ViewLocationCache {\r
  45             get;\r
  46             set;\r
  47         }\r
  48 \r
  49         [SuppressMessage("Microsoft.Performance", "CA1819:PropertiesShouldNotReturnArrays")]\r
  50         public string[] ViewLocationFormats {\r
  51             get;\r
  52             set;\r
  53         }\r
  54 \r
  55         protected VirtualPathProvider VirtualPathProvider {\r
  56             get {\r
  57                 if (_vpp == null) {\r
  58                     _vpp = HostingEnvironment.VirtualPathProvider;\r
  59                 }\r
  60                 return _vpp;\r
  61             }\r
  62             set {\r
  63                 _vpp = value;\r
  64             }\r
  65         }\r
  66 \r
  67         protected VirtualPathProviderViewEngine() {\r
  68             if (HttpContext.Current == null || HttpContext.Current.IsDebuggingEnabled) {\r
  69                 ViewLocationCache = DefaultViewLocationCache.Null;\r
  70             }\r
  71             else {\r
  72                 ViewLocationCache = new DefaultViewLocationCache();\r
  73             }\r
  74         }\r
  75 \r
  76         private string CreateCacheKey(string prefix, string name, string controllerName) {\r
  77             return String.Format(CultureInfo.InvariantCulture, _cacheKeyFormat,\r
  78                 GetType().AssemblyQualifiedName, prefix, name, controllerName);\r
  79         }\r
  80 \r
  81         protected abstract IView CreatePartialView(ControllerContext controllerContext, string partialPath);\r
  82 \r
  83         protected abstract IView CreateView(ControllerContext controllerContext, string viewPath, string masterPath);\r
  84 \r
  85         protected virtual bool FileExists(ControllerContext controllerContext, string virtualPath) {\r
  86             return VirtualPathProvider.FileExists(virtualPath);\r
  87         }\r
  88 \r
  89         public virtual ViewEngineResult FindPartialView(ControllerContext controllerContext, string partialViewName, bool useCache) {\r
  90             if (controllerContext == null) {\r
  91                 throw new ArgumentNullException("controllerContext");\r
  92             }\r
  93             if (String.IsNullOrEmpty(partialViewName)) {\r
  94                 throw new ArgumentException(MvcResources.Common_NullOrEmpty, "partialViewName");\r
  95             }\r
  96 \r
  97             string[] searched;\r
  98             string controllerName = controllerContext.RouteData.GetRequiredString("controller");\r
  99             string partialPath = GetPath(controllerContext, PartialViewLocationFormats, "PartialViewLocationFormats", partialViewName, controllerName, _cacheKeyPrefix_Partial, useCache, out searched);\r
 100 \r
 101             if (String.IsNullOrEmpty(partialPath)) {\r
 102                 return new ViewEngineResult(searched);\r
 103             }\r
 104 \r
 105             return new ViewEngineResult(CreatePartialView(controllerContext, partialPath), this);\r
 106         }\r
 107 \r
 108         public virtual ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache) {\r
 109             if (controllerContext == null) {\r
 110                 throw new ArgumentNullException("controllerContext");\r
 111             }\r
 112             if (String.IsNullOrEmpty(viewName)) {\r
 113                 throw new ArgumentException(MvcResources.Common_NullOrEmpty, "viewName");\r
 114             }\r
 115 \r
 116             string[] viewLocationsSearched;\r
 117             string[] masterLocationsSearched;\r
 118 \r
 119             string controllerName = controllerContext.RouteData.GetRequiredString("controller");\r
 120             string viewPath = GetPath(controllerContext, ViewLocationFormats, "ViewLocationFormats", viewName, controllerName, _cacheKeyPrefix_View, useCache, out viewLocationsSearched);\r
 121             string masterPath = GetPath(controllerContext, MasterLocationFormats, "MasterLocationFormats", masterName, controllerName, _cacheKeyPrefix_Master, useCache, out masterLocationsSearched);\r
 122 \r
 123             if (String.IsNullOrEmpty(viewPath) || (String.IsNullOrEmpty(masterPath) && !String.IsNullOrEmpty(masterName))) {\r
 124                 return new ViewEngineResult(viewLocationsSearched.Union(masterLocationsSearched));\r
 125             }\r
 126 \r
 127             return new ViewEngineResult(CreateView(controllerContext, viewPath, masterPath), this);\r
 128         }\r
 129 \r
 130         private string GetPath(ControllerContext controllerContext, string[] locations, string locationsPropertyName, string name, string controllerName, string cacheKeyPrefix, bool useCache, out string[] searchedLocations) {\r
 131             searchedLocations = _emptyLocations;\r
 132 \r
 133             if (String.IsNullOrEmpty(name)) {\r
 134                 return String.Empty;\r
 135             }\r
 136 \r
 137             if (locations == null || locations.Length == 0) {\r
 138                 throw new InvalidOperationException(String.Format(CultureInfo.CurrentUICulture,\r
 139                     MvcResources.Common_PropertyCannotBeNullOrEmpty, locationsPropertyName));\r
 140             }\r
 141 \r
 142             bool nameRepresentsPath = IsSpecificPath(name);\r
 143             string cacheKey = CreateCacheKey(cacheKeyPrefix, name, (nameRepresentsPath) ? String.Empty : controllerName);\r
 144 \r
 145             if (useCache) {\r
 146                 string result = ViewLocationCache.GetViewLocation(controllerContext.HttpContext, cacheKey);\r
 147                 if (result != null) {\r
 148                     return result;\r
 149                 }\r
 150             }\r
 151 \r
 152             return (nameRepresentsPath) ?\r
 153                 GetPathFromSpecificName(controllerContext, name, cacheKey, ref searchedLocations) :\r
 154                 GetPathFromGeneralName(controllerContext, locations, name, controllerName, cacheKey, ref searchedLocations);\r
 155         }\r
 156 \r
 157         private string GetPathFromGeneralName(ControllerContext controllerContext, string[] locations, string name, string controllerName, string cacheKey, ref string[] searchedLocations) {\r
 158             string result = String.Empty;\r
 159             searchedLocations = new string[locations.Length];\r
 160 \r
 161             for (int i = 0; i < locations.Length; i++) {\r
 162                 string virtualPath = String.Format(CultureInfo.InvariantCulture, locations[i], name, controllerName);\r
 163 \r
 164                 if (FileExists(controllerContext, virtualPath)) {\r
 165                     searchedLocations = _emptyLocations;\r
 166                     result = virtualPath;\r
 167                     ViewLocationCache.InsertViewLocation(controllerContext.HttpContext, cacheKey, result);\r
 168                     break;\r
 169                 }\r
 170 \r
 171                 searchedLocations[i] = virtualPath;\r
 172             }\r
 173 \r
 174             return result;\r
 175         }\r
 176 \r
 177         private string GetPathFromSpecificName(ControllerContext controllerContext, string name, string cacheKey, ref string[] searchedLocations) {\r
 178             string result = name;\r
 179 \r
 180             if (!FileExists(controllerContext, name)) {\r
 181                 result = String.Empty;\r
 182                 searchedLocations = new[] { name };\r
 183             }\r
 184 \r
 185             ViewLocationCache.InsertViewLocation(controllerContext.HttpContext, cacheKey, result);\r
 186             return result;\r
 187         }\r
 188 \r
 189         private static bool IsSpecificPath(string name) {\r
 190             char c = name[0];\r
 191             return (c == '~' || c == '/');\r
 192         }\r
 193 \r
 194         public virtual void ReleaseView(ControllerContext controllerContext, IView view) {\r
 195             IDisposable disposable = view as IDisposable;\r
 196             if (disposable != null) {\r
 197                 disposable.Dispose();\r
 198             }\r
 199         }\r
 200     }\r
 201 }