mcs/class/System.Web/System.Web.Configuration/HttpHandlersSectionHandler.cs

   1 //
   2 // System.Web.Configuration.HttpHandlersSectionHandler
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2002 Ximian, Inc (http://www.ximian.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.Collections;
  32 using System.Configuration;
  33 using System.Xml;
  34
  35 namespace System.Web.Configuration
  36 {
  37         class HttpHandlersSectionHandler : IConfigurationSectionHandler
  38         {
  39                 public virtual object Create (object parent, object configContext, XmlNode section)
  40                 {
  41                         HandlerFactoryConfiguration mapper;
  42
  43                         if (parent is HandlerFactoryConfiguration)
  44                                 mapper = new HandlerFactoryConfiguration ((HandlerFactoryConfiguration) parent);
  45                         else
  46                                 mapper = new HandlerFactoryConfiguration (null);
  47
  48                         if (section.Attributes != null && section.Attributes.Count != 0)
  49                                 HandlersUtil.ThrowException ("Unrecognized attribute", section);
  50
  51                         XmlNodeList httpHandlers = section.ChildNodes;
  52                         foreach (XmlNode child in httpHandlers) {
  53                                 XmlNodeType ntype = child.NodeType;
  54                                 if (ntype == XmlNodeType.Whitespace || ntype == XmlNodeType.Comment)
  55                                         continue;
  56
  57                                 if (ntype != XmlNodeType.Element)
  58                                         HandlersUtil.ThrowException ("Only elements allowed", child);
  59
  60                                 string name = child.Name;
  61                                 if (name == "clear") {
  62                                         if (child.Attributes != null && child.Attributes.Count != 0)
  63                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  64
  65                                         mapper.Clear ();
  66                                         continue;
  67                                 }
  68
  69                                 string verb = HandlersUtil.ExtractAttributeValue ("verb", child);
  70                                 string path = HandlersUtil.ExtractAttributeValue ("path", child);
  71                                 string validateStr = HandlersUtil.ExtractAttributeValue ("validate", child, true);
  72                                 bool validate;
  73                                 if (validateStr == null) {
  74                                         validate = true;
  75                                 } else {
  76                                         validate = validateStr == "true";
  77                                         if (!validate && validateStr != "false")
  78                                                 HandlersUtil.ThrowException (
  79                                                                 "Invalid value for validate attribute.", child);
  80                                 }
  81
  82                                 if (name == "add") {
  83                                         string type = HandlersUtil.ExtractAttributeValue ("type", child);
  84                                         if (child.Attributes != null && child.Attributes.Count != 0)
  85                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  86
  87                                         mapper.Add (verb, path, type, validate);
  88                                         continue;
  89                                 }
  90
  91                                 if (name == "remove") {
  92                                         if (child.Attributes != null && child.Attributes.Count != 0)
  93                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  94
  95                                         if (validate && mapper.Remove (verb, path) == null)
  96                                                 HandlersUtil.ThrowException ("There's no mapping to remove", child);
  97
  98                                         continue;
  99                                 }
 100                                 HandlersUtil.ThrowException ("Unexpected element", child);
 101                         }
 102
 103                         return mapper;
 104                 }
 105         }
 106
 107         internal class HandlersUtil
 108         {
 109                 private HandlersUtil ()
 110                 {
 111                 }
 112
 113                 static internal string ExtractAttributeValue (string attKey, XmlNode node)
 114                 {
 115                         return ExtractAttributeValue (attKey, node, false);
 116                 }
 117
 118                 static internal string ExtractAttributeValue (string attKey, XmlNode node, bool optional)
 119                 {
 120                         return ExtractAttributeValue (attKey, node, optional, false);
 121                 }
 122
 123                 static internal string ExtractAttributeValue (string attKey, XmlNode node, bool optional,
 124                                                               bool allowEmpty)
 125                 {
 126                         if (node.Attributes == null) {
 127                                 if (optional)
 128                                         return null;
 129
 130                                 ThrowException ("Required attribute not found: " + attKey, node);
 131                         }
 132
 133                         XmlNode att = node.Attributes.RemoveNamedItem (attKey);
 134                         if (att == null) {
 135                                 if (optional)
 136                                         return null;
 137                                 ThrowException ("Required attribute not found: " + attKey, node);
 138                         }
 139
 140                         string value = att.Value;
 141                         if (!allowEmpty && value == String.Empty) {
 142                                 string opt = optional ? "Optional" : "Required";
 143                                 ThrowException (opt + " attribute is empty: " + attKey, node);
 144                         }
 145
 146                         return value;
 147                 }
 148
 149                 static internal void ThrowException (string msg, XmlNode node)
 150                 {
 151                         if (node != null && node.Name != String.Empty)
 152                                 msg = msg + " (node name: " + node.Name + ") ";
 153                         throw new ConfigurationException (msg, node);
 154                 }
 155         }
 156 }
 157