mcs/class/System/System.Net.Configuration/ConnectionManagementHandler.cs

   1 //
   2 // System.Net.Configuration.ConnectionManagementHandler
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2003 Ximian, Inc (http://www.ximian.com)
   8 //
   9
  10 using System.Collections;
  11 using System.Configuration;
  12 using System.Xml;
  13
  14 namespace System.Net.Configuration
  15 {
  16         class ConnectionManagementData
  17         {
  18                 Hashtable data; // key -> address, value -> maxconnections
  19
  20                 public ConnectionManagementData (object parent)
  21                 {
  22                         data = new Hashtable ();
  23                         if (parent != null && parent is ConnectionManagementData) {
  24                                 ConnectionManagementData p = (ConnectionManagementData) parent;
  25                                 foreach (string k in p.data.Keys)
  26                                         data [k] = p.data [k];
  27                         }
  28                 }
  29
  30                 public void Add (string address, string nconns)
  31                 {
  32                         if (nconns == null || nconns == "")
  33                                 nconns = "2";
  34                         // Adding duplicates works fine under MS, so...
  35                         data [address] = UInt32.Parse (nconns);
  36                 }
  37
  38                 public void Remove (string address)
  39                 {
  40                         // Removing non-existent address is fine.
  41                         data.Remove (address);
  42                 }
  43
  44                 public void Clear ()
  45                 {
  46                         data.Clear ();
  47                 }
  48
  49                 public Hashtable Data {
  50                         get { return data; }
  51                 }
  52         }
  53
  54         class ConnectionManagementHandler : IConfigurationSectionHandler
  55         {
  56                 public virtual object Create (object parent, object configContext, XmlNode section)
  57                 {
  58                         ConnectionManagementData cmd = new ConnectionManagementData (parent);
  59
  60                         if (section.Attributes != null && section.Attributes.Count != 0)
  61                                 HandlersUtil.ThrowException ("Unrecognized attribute", section);
  62
  63                         XmlNodeList httpHandlers = section.ChildNodes;
  64                         foreach (XmlNode child in httpHandlers) {
  65                                 XmlNodeType ntype = child.NodeType;
  66                                 if (ntype == XmlNodeType.Whitespace || ntype == XmlNodeType.Comment)
  67                                         continue;
  68
  69                                 if (ntype != XmlNodeType.Element)
  70                                         HandlersUtil.ThrowException ("Only elements allowed", child);
  71
  72                                 string name = child.Name;
  73                                 if (name == "clear") {
  74                                         if (child.Attributes != null && child.Attributes.Count != 0)
  75                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  76
  77                                         cmd.Clear ();
  78                                         continue;
  79                                 }
  80
  81                                 //LAMESPEC: the MS doc says that <remove name="..."/> but they throw an exception
  82                                 // if you use that. "address" is correct.
  83
  84                                 string address = HandlersUtil.ExtractAttributeValue ("address", child);
  85                                 if (name == "add") {
  86                                         string maxcnc = HandlersUtil.ExtractAttributeValue ("maxconnection", child, true);
  87                                         if (child.Attributes != null && child.Attributes.Count != 0)
  88                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  89
  90                                         cmd.Add (address, maxcnc);
  91                                         continue;
  92                                 }
  93
  94                                 if (name == "remove") {
  95                                         if (child.Attributes != null && child.Attributes.Count != 0)
  96                                                 HandlersUtil.ThrowException ("Unrecognized attribute", child);
  97
  98                                         cmd.Remove (address);
  99                                         continue;
 100                                 }
 101
 102                                 HandlersUtil.ThrowException ("Unexpected element", child);
 103                         }
 104
 105                         return cmd;
 106                 }
 107         }
 108
 109         internal class HandlersUtil
 110         {
 111                 private HandlersUtil ()
 112                 {
 113                 }
 114
 115                 static internal string ExtractAttributeValue (string attKey, XmlNode node)
 116                 {
 117                         return ExtractAttributeValue (attKey, node, false);
 118                 }
 119
 120                 static internal string ExtractAttributeValue (string attKey, XmlNode node, bool optional)
 121                 {
 122                         if (node.Attributes == null) {
 123                                 if (optional)
 124                                         return null;
 125
 126                                 ThrowException ("Required attribute not found: " + attKey, node);
 127                         }
 128
 129                         XmlNode att = node.Attributes.RemoveNamedItem (attKey);
 130                         if (att == null) {
 131                                 if (optional)
 132                                         return null;
 133                                 ThrowException ("Required attribute not found: " + attKey, node);
 134                         }
 135
 136                         string value = att.Value;
 137                         if (value == String.Empty) {
 138                                 string opt = optional ? "Optional" : "Required";
 139                                 ThrowException (opt + " attribute is empty: " + attKey, node);
 140                         }
 141
 142                         return value;
 143                 }
 144
 145                 static internal void ThrowException (string msg, XmlNode node)
 146                 {
 147                         if (node != null && node.Name != String.Empty)
 148                                 msg = msg + " (node name: " + node.Name + ") ";
 149                         throw new ConfigurationException (msg, node);
 150                 }
 151         }
 152 }
 153