mcs/class/System.Web/System.Web.Caching/OutputCacheModule.cs

   1 //
   2 // System.Web.Caching.OutputCacheModule
   3 //
   4 // Authors:
   5 //  Jackson Harper (jackson@ximian.com)
   6 //
   7 // (C) 2003 Novell, Inc (http://www.novell.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System.IO;
  32 using System.Web;
  33 using System.Web.UI;
  34 using System.Web.Util;
  35 using System.Collections;
  36 using System.Web.Compilation;
  37
  38 #if NET_2_0
  39 using System.Collections.Generic;
  40 #endif
  41
  42 namespace System.Web.Caching {
  43
  44         internal sealed class OutputCacheModule : IHttpModule {
  45
  46                 CacheItemRemovedCallback response_removed;
  47
  48 #if NET_2_0
  49                 static object keysCacheLock = new object ();
  50                 Dictionary <string, string> keysCache;
  51                 Dictionary <string, string> entriesToInvalidate;
  52 #endif
  53
  54                 public OutputCacheModule ()
  55                 {
  56                 }
  57
  58                 public void Dispose ()
  59                 {
  60                 }
  61
  62                 public void Init (HttpApplication app)
  63                 {
  64                         app.ResolveRequestCache += new EventHandler(OnResolveRequestCache);
  65                         app.UpdateRequestCache += new EventHandler(OnUpdateRequestCache);
  66 #if NET_2_0
  67                         keysCache = new Dictionary <string, string> ();
  68                         entriesToInvalidate = new Dictionary <string, string> ();
  69                         BuildManager.RemoveEntry += new BuildManagerRemoveEntryEventHandler (OnBuildManagerRemoveEntry);
  70 #endif
  71                         response_removed = new CacheItemRemovedCallback (OnRawResponseRemoved);
  72                 }
  73
  74 #if NET_2_0
  75                 void OnBuildManagerRemoveEntry (BuildManagerRemoveEntryEventArgs args)
  76                 {
  77                         string entry = args.EntryName;
  78                         HttpContext context = args.Context;
  79                         string cacheValue;
  80
  81                         lock (keysCacheLock) {
  82                                 if (!keysCache.TryGetValue (entry, out cacheValue))
  83                                         return;
  84
  85                                 keysCache.Remove (entry);
  86                                 if (context == null && !entriesToInvalidate.ContainsKey (entry)) {
  87                                         entriesToInvalidate.Add (entry, cacheValue);
  88                                         return;
  89                                 }
  90                         }
  91
  92                         context.Cache.Remove (entry);
  93                         if (!String.IsNullOrEmpty (cacheValue))
  94                                 context.InternalCache.Remove (cacheValue);
  95                 }
  96 #endif
  97
  98                 void OnResolveRequestCache (object o, EventArgs args)
  99                 {
 100                         HttpApplication app = (HttpApplication) o;
 101                         HttpContext context = app.Context;
 102
 103                         string vary_key = context.Request.FilePath;
 104                         CachedVaryBy varyby = context.Cache [vary_key] as CachedVaryBy;
 105                         string key;
 106                         CachedRawResponse c;
 107
 108                         if (varyby == null)
 109                                 return;
 110
 111                         key = varyby.CreateKey (vary_key, context);
 112                         c = context.InternalCache [key] as CachedRawResponse;
 113                         if (c == null)
 114                                 return;
 115
 116 #if NET_2_0
 117                         lock (keysCacheLock) {
 118                                 string invValue;
 119                                 if (entriesToInvalidate.TryGetValue (vary_key, out invValue) && String.Compare (invValue, key, StringComparison.Ordinal) == 0) {
 120                                         context.Cache.Remove (vary_key);
 121                                         context.InternalCache.Remove (key);
 122                                         entriesToInvalidate.Remove (vary_key);
 123                                         return;
 124                                 }
 125                         }
 126 #endif
 127
 128                         ArrayList callbacks = c.Policy.ValidationCallbacks;
 129                         if (callbacks != null && callbacks.Count > 0) {
 130                                 bool isValid = true;
 131                                 bool isIgnored = false;
 132
 133                                 foreach (Pair p in callbacks) {
 134                                         HttpCacheValidateHandler validate = (HttpCacheValidateHandler)p.First;
 135                                         object data = p.Second;
 136                                         HttpValidationStatus status = HttpValidationStatus.Valid;
 137
 138                                         try {
 139                                                 validate (context, data, ref status);
 140                                         } catch {
 141                                                 // MS.NET hides the exception
 142                                                 isValid = false;
 143                                                 break;
 144                                         }
 145
 146                                         if (status == HttpValidationStatus.Invalid) {
 147                                                 isValid = false;
 148                                                 break;
 149                                         } else if (status == HttpValidationStatus.IgnoreThisRequest) {
 150                                                 isIgnored = true;
 151                                         }
 152                                 }
 153
 154                                 if (!isValid) {
 155                                         OnRawResponseRemoved (key, c, CacheItemRemovedReason.Removed);
 156                                         return;
 157                                 } else if (isIgnored) {
 158                                         return;
 159                                 }
 160                         }
 161
 162                         context.Response.ClearContent ();
 163                         context.Response.BinaryWrite (c.GetData (), 0, c.ContentLength);
 164
 165                         context.Response.ClearHeaders ();
 166                         context.Response.SetCachedHeaders (c.Headers);
 167
 168                         context.Response.StatusCode = c.StatusCode;
 169                         context.Response.StatusDescription = c.StatusDescription;
 170
 171                         app.CompleteRequest ();
 172                 }
 173
 174                 void OnUpdateRequestCache (object o, EventArgs args)
 175                 {
 176                         HttpApplication app = (HttpApplication) o;
 177                         HttpContext context = app.Context;
 178
 179                         if (context.Response.IsCached && context.Response.StatusCode == 200 &&
 180                             !context.Trace.IsEnabled)
 181                                 DoCacheInsert (context);
 182
 183                 }
 184
 185                 void DoCacheInsert (HttpContext context)
 186                 {
 187                         string vary_key = context.Request.FilePath;
 188                         string key;
 189                         CachedVaryBy varyby = context.Cache [vary_key] as CachedVaryBy;
 190                         CachedRawResponse prev = null;
 191                         bool lookup = true;
 192 #if NET_2_0
 193                         string cacheKey = null, cacheValue = null;
 194 #endif
 195
 196                         if (varyby == null) {
 197                                 string path = context.Request.MapPath (vary_key);
 198                                 string [] files = new string [] { path };
 199                                 string [] keys = new string [0];
 200                                 varyby = new CachedVaryBy (context.Response.Cache, vary_key);
 201                                 context.Cache.Insert (vary_key, varyby,
 202                                                               new CacheDependency (files, keys),
 203                                                               Cache.NoAbsoluteExpiration,
 204                                                               Cache.NoSlidingExpiration,
 205                                                               CacheItemPriority.Normal, null);
 206                                 lookup = false;
 207 #if NET_2_0
 208                                 cacheKey = vary_key;
 209 #endif
 210                         }
 211
 212                         key = varyby.CreateKey (vary_key, context);
 213
 214                         if (lookup)
 215                                 prev = context.InternalCache [key] as CachedRawResponse;
 216
 217                         if (prev == null) {
 218                                 CachedRawResponse c = context.Response.GetCachedResponse ();
 219                                 string [] files = new string [] { };
 220                                 string [] keys = new string [] { vary_key };
 221                                 bool sliding = context.Response.Cache.Sliding;
 222
 223                                 context.InternalCache.Insert (key, c, new CacheDependency (files, keys),
 224                                                               (sliding ? Cache.NoAbsoluteExpiration :
 225                                                                context.Response.Cache.Expires),
 226                                                               (sliding ? TimeSpan.FromSeconds (
 227                                                                       context.Response.Cache.Duration) :
 228                                                                Cache.NoSlidingExpiration),
 229                                                               CacheItemPriority.Normal, response_removed);
 230                                 c.VaryBy = varyby;
 231                                 varyby.ItemList.Add (key);
 232 #if NET_2_0
 233                                 cacheValue = key;
 234 #endif
 235                         }
 236
 237 #if NET_2_0
 238                         if (cacheKey != null) {
 239                                 lock (keysCacheLock) {
 240                                         if (!keysCache.ContainsKey (cacheKey))
 241                                                 keysCache.Add (cacheKey, cacheValue);
 242                                 }
 243                         }
 244 #endif
 245                 }
 246
 247                 void OnRawResponseRemoved (string key, object value, CacheItemRemovedReason reason)
 248                 {
 249                         CachedRawResponse c = (CachedRawResponse) value;
 250
 251                         c.VaryBy.ItemList.Remove (key);
 252                         if (c.VaryBy.ItemList.Count != 0)
 253                                 return;
 254
 255                         HttpRuntime.Cache.Remove (c.VaryBy.Key);
 256                 }
 257         }
 258 }
 259