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

   1 //
   2 // Authors:
   3 //   Marek Habersack <mhabersack@novell.com>
   4 //
   5 // (C) 2010 Novell, Inc (http://novell.com/)
   6 //
   7
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System.Configuration;
  30 using System.Configuration.Provider;
  31 using System.IO;
  32 using System.Runtime.Serialization.Formatters.Binary;
  33 using System.Security.Permissions;
  34 using System.Web;
  35 using System.Web.Configuration;
  36
  37 namespace System.Web.Caching
  38 {
  39         public static class OutputCache
  40         {
  41                 internal const string DEFAULT_PROVIDER_NAME = "AspNetInternalProvider";
  42
  43                 static readonly object initLock = new object ();
  44                 static readonly object defaultProviderInitLock = new object();
  45
  46                 static bool initialized;
  47                 static string defaultProviderName;
  48                 static OutputCacheProviderCollection providers;
  49                 static OutputCacheProvider defaultProvider;
  50
  51                 public static string DefaultProviderName {
  52                         get {
  53                                 Init ();
  54                                 if (String.IsNullOrEmpty (defaultProviderName))
  55                                         return DEFAULT_PROVIDER_NAME;
  56
  57                                 return defaultProviderName;
  58                         }
  59                 }
  60
  61                 internal static OutputCacheProvider DefaultProvider {
  62                         get {
  63                                 if (defaultProvider == null) {
  64                                         lock (defaultProviderInitLock) {
  65                                                 if (defaultProvider == null)
  66                                                         defaultProvider = new InMemoryOutputCacheProvider ();
  67                                         }
  68                                 }
  69
  70                                 return defaultProvider;
  71                         }
  72                 }
  73
  74                 public static OutputCacheProviderCollection Providers {
  75                         get {
  76                                 Init ();
  77                                 return providers;
  78                         }
  79                 }
  80
  81                 [SecurityPermission (SecurityAction.Assert, Flags = SecurityPermissionFlag.SerializationFormatter)]
  82                 public static object Deserialize (Stream stream)
  83                 {
  84                         if (stream == null)
  85                                 throw new ArgumentNullException ("stream");
  86
  87                         object o = new BinaryFormatter ().Deserialize (stream);
  88                         if (o == null || IsInvalidType (o))
  89                                 throw new ArgumentException ("The provided parameter is not of a supported type for serialization and/or deserialization.");
  90
  91                         return o;
  92                 }
  93
  94                 [SecurityPermission (SecurityAction.Assert, Flags = SecurityPermissionFlag.SerializationFormatter)]
  95                 public static void Serialize (Stream stream, object data)
  96                 {
  97                         if (stream == null)
  98                                 throw new ArgumentNullException ("stream");
  99
 100                         // LAMESPEC: data == null doesn't throw ArgumentNullException
 101                         if (data == null || IsInvalidType (data))
 102                                 throw new ArgumentException ("The provided parameter is not of a supported type for serialization and/or deserialization.");
 103
 104                         new BinaryFormatter ().Serialize (stream, data);
 105                 }
 106
 107                 internal static OutputCacheProvider GetProvider (string providerName)
 108                 {
 109                         if (String.IsNullOrEmpty (providerName))
 110                                 return null;
 111
 112                         if (String.Compare (providerName, DEFAULT_PROVIDER_NAME, StringComparison.Ordinal) == 0)
 113                                 return DefaultProvider;
 114
 115                         OutputCacheProviderCollection providers = OutputCache.Providers;
 116                         return (providers != null ? providers [providerName] : null);
 117                 }
 118
 119                 static bool IsInvalidType (object data)
 120                 {
 121                         return !(data is MemoryResponseElement) &&
 122                                 !(data is FileResponseElement) &&
 123                                 !(data is SubstitutionResponseElement);
 124                 }
 125
 126                 static void Init ()
 127                 {
 128                         if (initialized)
 129                                 return;
 130
 131                         lock (initLock) {
 132                                 if (initialized)
 133                                         return;
 134
 135                                 var cfg = WebConfigurationManager.GetWebApplicationSection ("system.web/caching/outputCache") as OutputCacheSection;
 136                                 ProviderSettingsCollection cfgProviders = cfg.Providers;
 137
 138                                 defaultProviderName = cfg.DefaultProviderName;
 139                                 if (cfgProviders != null && cfgProviders.Count > 0) {
 140                                         var coll = new OutputCacheProviderCollection ();
 141
 142                                         foreach (ProviderSettings ps in cfgProviders)
 143                                                 coll.Add (LoadProvider (ps));
 144
 145                                         coll.SetReadOnly ();
 146                                         providers = coll;
 147                                 }
 148
 149                                 initialized = true;
 150                         }
 151                 }
 152
 153                 static OutputCacheProvider LoadProvider (ProviderSettings ps)
 154                 {
 155                         Type type = HttpApplication.LoadType (ps.Type, false);
 156                         if (type == null)
 157                                 throw new ConfigurationErrorsException (String.Format ("Could not load type '{0}'.", ps.Type));
 158
 159                         var ret = Activator.CreateInstance (type) as OutputCacheProvider;
 160                         ret.Initialize (ps.Name, ps.Parameters);
 161
 162                         return ret;
 163                 }
 164
 165                 internal static void RemoveFromProvider (string key, string providerName)
 166                 {
 167                         if (providerName == null)
 168                                 return;
 169
 170                         OutputCacheProviderCollection providers = Providers;
 171                         OutputCacheProvider provider;
 172
 173                         if (providers == null || providers.Count == 0)
 174                                 provider = null;
 175                         else
 176                                 provider = providers [providerName];
 177
 178                         if (provider == null)
 179                                 throw new ProviderException ("Provider '" + providerName + "' was not found.");
 180
 181                         provider.Remove (key);
 182                 }
 183         }
 184 }