mcs/class/System.Web/System.Web.UI/BasePartialCachingControl.cs

   1 //
   2 // System.Web.UI.BasePartialCachingControl.cs
   3 //
   4 // Author:
   5 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   6 //   Jackson Harper (jackson@ximian.com)
   7 //
   8 // (C) 2003 Andreas Nahr
   9 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  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.Text;
  33 using System.ComponentModel;
  34 using System.Security.Permissions;
  35 using System.Web.Caching;
  36
  37 namespace System.Web.UI
  38 {
  39         // CAS
  40         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  41         [AspNetHostingPermission (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  42         // attributes
  43         [ToolboxItem (false)]
  44         public abstract class BasePartialCachingControl : Control
  45         {
  46                 CacheDependency dependency;
  47                 string ctrl_id;
  48                 string guid;
  49                 int duration;
  50                 string varyby_params;
  51                 string varyby_controls;
  52                 string varyby_custom;
  53                 DateTime expirationTime;
  54                 bool slidingExpiration;
  55
  56                 Control control;
  57                 ControlCachePolicy cachePolicy;
  58
  59                 protected BasePartialCachingControl()
  60                 {
  61                 }
  62
  63                 internal string CtrlID {
  64                         get { return ctrl_id; }
  65                         set { ctrl_id = value; }
  66                 }
  67
  68                 internal string Guid {
  69                         get { return guid; }
  70                         set { guid = value; }
  71                 }
  72
  73                 internal int Duration {
  74                         get { return duration; }
  75                         set { duration = value; }
  76                 }
  77
  78                 internal string VaryByParams {
  79                         get { return varyby_params; }
  80                         set { varyby_params = value; }
  81                 }
  82
  83                 internal string VaryByControls {
  84                         get { return varyby_controls; }
  85                         set { varyby_controls = value; }
  86                 }
  87
  88                 internal string VaryByCustom {
  89                         get { return varyby_custom; }
  90                         set { varyby_custom = value; }
  91                 }
  92
  93                 internal DateTime ExpirationTime {
  94                         get { return expirationTime; }
  95                         set { expirationTime = value; }
  96                 }
  97
  98                 internal bool SlidingExpiration {
  99                         get { return slidingExpiration; }
 100                         set { slidingExpiration = value; }
 101                 }
 102
 103                 internal abstract Control CreateControl ();
 104
 105                 public override void Dispose ()
 106                 {
 107                         if (dependency != null) {
 108                                 dependency.Dispose ();
 109                                 dependency = null;
 110                         }
 111                 }
 112
 113                 protected internal override void OnInit (EventArgs e)
 114                 {
 115                         control = CreateControl ();
 116                         Controls.Add (control);
 117                 }
 118
 119                 protected internal override void Render (HtmlTextWriter output)
 120                 {
 121                         Cache cache = HttpRuntime.InternalCache;
 122                         string key = CreateKey ();
 123                         string data = cache [key] as string;
 124
 125                         if (data != null) {
 126                                 output.Write (data);
 127                                 return;
 128                         }
 129
 130                         HttpContext context = HttpContext.Current;
 131                         StringWriter writer = new StringWriter ();
 132                         TextWriter prev = context.Response.SetTextWriter (writer);
 133                         HtmlTextWriter txt_writer = new HtmlTextWriter (writer);
 134                         string text;
 135                         try {
 136                                 control.RenderControl (txt_writer);
 137                         } finally {
 138                                 text = writer.ToString ();
 139                                 context.Response.SetTextWriter (prev);
 140                                 output.Write (text);
 141                         }
 142
 143                         context.InternalCache.Insert (key, text, dependency,
 144                                                       DateTime.Now.AddSeconds (duration),
 145                                                       Cache.NoSlidingExpiration,
 146                                                       CacheItemPriority.Normal, null);
 147                 }
 148
 149                 public ControlCachePolicy CachePolicy
 150                 {
 151                         get {
 152                                 if (cachePolicy == null)
 153                                         cachePolicy = new ControlCachePolicy (this);
 154
 155                                 return cachePolicy;
 156                         }
 157                 }
 158
 159                 public CacheDependency Dependency {
 160                         get {return dependency;}
 161                         set {dependency = value;}
 162                 }
 163
 164                 string CreateKey ()
 165                 {
 166                         StringBuilder builder = new StringBuilder ();
 167                         HttpContext context = HttpContext.Current;
 168
 169                         builder.Append ("PartialCachingControl\n");
 170                         builder.Append ("GUID: " + guid + "\n");
 171
 172                         if (varyby_params != null && varyby_params.Length > 0) {
 173                                 string[] prms = varyby_params.Split (';');
 174                                 for (int i=0; i<prms.Length; i++) {
 175                                         string val = context.Request.Params [prms [i]];
 176                                         builder.Append ("VP:");
 177                                         builder.Append (prms [i]);
 178                                         builder.Append ('=');
 179                                         builder.Append (val != null ? val : "__null__");
 180                                         builder.Append ('\n');
 181                                 }
 182                         }
 183
 184                         if (varyby_controls != null && varyby_params.Length > 0) {
 185                                 string[] prms = varyby_controls.Split (';');
 186                                 for (int i=0; i<prms.Length; i++) {
 187                                         string val = context.Request.Params [prms [i]];
 188                                         builder.Append ("VCN:");
 189                                         builder.Append (prms [i]);
 190                                         builder.Append ('=');
 191                                         builder.Append (val != null ? val : "__null__");
 192                                         builder.Append ('\n');
 193                                 }
 194                         }
 195
 196                         if (varyby_custom != null) {
 197                                 string val = context.ApplicationInstance.GetVaryByCustomString (context,
 198                                                 varyby_custom);
 199                                 builder.Append ("VC:");
 200                                 builder.Append (varyby_custom);
 201                                 builder.Append ('=');
 202                                 builder.Append (val != null ? val : "__null__");
 203                                 builder.Append ('\n');
 204                         }
 205
 206                         return builder.ToString ();
 207                 }
 208         }
 209 }
 210