mcs/class/System.ServiceModel.Web/System/UriTemplate.cs

   1 //
   2 // UriTemplate.cs
   3 //
   4 // Author:
   5 //      Atsushi Enomoto  <atsushi@ximian.com>
   6 //
   7 // Copyright (C) 2008 Novell, Inc (http://www.novell.com)
   8 // Copyright 2011 Xamarin Inc (http://www.xamarin.com).
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29 using System;
  30 using System.Collections.Generic;
  31 using System.Collections.ObjectModel;
  32 using System.Collections.Specialized;
  33 using System.Globalization;
  34 using System.Text;
  35
  36 namespace System
  37 {
  38         public class UriTemplate
  39         {
  40                 static readonly ReadOnlyCollection<string> empty_strings = new ReadOnlyCollection<string> (new string [0]);
  41
  42                 string template;
  43                 ReadOnlyCollection<string> path, query;
  44                 string wild_path_name;
  45                 Dictionary<string,string> query_params = new Dictionary<string,string> ();
  46
  47                 public UriTemplate (string template)
  48                         : this (template, false)
  49                 {
  50                 }
  51
  52                 public UriTemplate (string template, IDictionary<string,string> additionalDefaults)
  53                         : this (template, false, additionalDefaults)
  54                 {
  55                 }
  56
  57                 public UriTemplate (string template, bool ignoreTrailingSlash)
  58                         : this (template, ignoreTrailingSlash, null)
  59                 {
  60                 }
  61
  62                 public UriTemplate (string template, bool ignoreTrailingSlash, IDictionary<string,string> additionalDefaults)
  63                 {
  64                         if (template == null)
  65                                 throw new ArgumentNullException ("template");
  66                         this.template = template;
  67                         IgnoreTrailingSlash = ignoreTrailingSlash;
  68                         Defaults = new Dictionary<string,string> (StringComparer.InvariantCultureIgnoreCase);
  69                         if (additionalDefaults != null)
  70                                 foreach (var pair in additionalDefaults)
  71                                         Defaults.Add (pair.Key, pair.Value);
  72
  73                         string p = template;
  74                         // Trim scheme, host name and port if exist.
  75                         if (CultureInfo.InvariantCulture.CompareInfo.IsPrefix (template, "http")) {
  76                                 int idx = template.IndexOf ('/', 8); // after "http://x" or "https://"
  77                                 if (idx > 0)
  78                                         p = template.Substring (idx);
  79                         }
  80                         int q = p.IndexOf ('?');
  81                         path = ParsePathTemplate (p, 0, q >= 0 ? q : p.Length);
  82                         if (q >= 0)
  83                                 ParseQueryTemplate (p, q, p.Length);
  84                         else
  85                                 query = empty_strings;
  86                 }
  87
  88                 public bool IgnoreTrailingSlash { get; private set; }
  89
  90                 public IDictionary<string,string> Defaults { get; private set; }
  91
  92                 public ReadOnlyCollection<string> PathSegmentVariableNames {
  93                         get { return path; }
  94                 }
  95
  96                 public ReadOnlyCollection<string> QueryValueVariableNames {
  97                         get { return query; }
  98                 }
  99
 100                 public override string ToString ()
 101                 {
 102                         return template;
 103                 }
 104
 105                 // Bind
 106
 107                 public Uri BindByName (Uri baseAddress, NameValueCollection parameters)
 108                 {
 109                         return BindByName (baseAddress, parameters, false);
 110                 }
 111
 112                 public Uri BindByName (Uri baseAddress, NameValueCollection parameters, bool omitDefaults)
 113                 {
 114                         return BindByNameCommon (baseAddress, parameters, null, omitDefaults);
 115                 }
 116
 117                 public Uri BindByName (Uri baseAddress, IDictionary<string,string> parameters)
 118                 {
 119                         return BindByName (baseAddress, parameters, false);
 120                 }
 121
 122                 public Uri BindByName (Uri baseAddress, IDictionary<string,string> parameters, bool omitDefaults)
 123                 {
 124                         return BindByNameCommon (baseAddress, null, parameters, omitDefaults);
 125                 }
 126
 127                 string SuffixEndRenderedUri (string s)
 128                 {
 129                         return s.Length > 0 && s [s.Length - 1] == '/' ? s : s + '/';
 130                 }
 131
 132                 string TrimStartRenderedUri (StringBuilder sb)
 133                 {
 134                         if (sb.Length == 0)
 135                                 return String.Empty;
 136
 137                         if (sb [0] == '/')
 138                                 return sb.ToString (1, sb.Length - 1);
 139
 140                         return sb.ToString ();
 141                 }
 142
 143                 Uri BindByNameCommon (Uri baseAddress, NameValueCollection nvc, IDictionary<string,string> dic, bool omitDefaults)
 144                 {
 145                         CheckBaseAddress (baseAddress);
 146
 147                         // take care of case sensitivity.
 148                         if (dic != null)
 149                                 dic = new Dictionary<string,string> (dic, StringComparer.OrdinalIgnoreCase);
 150
 151                         int src = 0;
 152                         StringBuilder sb = new StringBuilder (template.Length);
 153                         BindByName (ref src, sb, path, nvc, dic, omitDefaults, false);
 154                         BindByName (ref src, sb, query, nvc, dic, omitDefaults, true);
 155                         sb.Append (template.Substring (src));
 156                         return new Uri (SuffixEndRenderedUri (baseAddress.ToString ()) + TrimStartRenderedUri (sb));
 157                 }
 158
 159                 void BindByName (ref int src, StringBuilder sb, ReadOnlyCollection<string> names, NameValueCollection nvc, IDictionary<string,string> dic, bool omitDefaults, bool query)
 160                 {
 161                         if (query) {
 162                                 int idx = template.IndexOf ('?', src);
 163                                 if (idx > 0) {
 164                                         sb.Append (template.Substring (src, idx - src));
 165                                         src = idx;
 166                                         // note that it doesn't append '?'. It is added only when there is actual parameter binding.
 167                                 }
 168                         }
 169
 170                         foreach (string name in names) {
 171                                 int s = template.IndexOf ('{', src);
 172                                 int e = template.IndexOf ('}', s + 1);
 173                                 string value = nvc != null ? nvc [name] : null;
 174
 175                                 if (dic != null)
 176                                         dic.TryGetValue (name, out value);
 177
 178                                 if (query) {
 179                                         if (value != null || (!omitDefaults && Defaults.TryGetValue (name, out value))) {
 180                                                 sb.Append (template.Substring (src, s - src));
 181                                                 sb.Append (value);
 182                                         }
 183                                 } else {
 184                                         if (value == null && (omitDefaults || !Defaults.TryGetValue (name, out value)))
 185                                                 throw new ArgumentException (string.Format("The argument name value collection does not contain non-null value for '{0}'", name), "parameters");
 186
 187                                         sb.Append (template.Substring (src, s - src));
 188                                         sb.Append (value);
 189                                 }
 190                                 src = e + 1;
 191                         }
 192                 }
 193
 194                 public Uri BindByPosition (Uri baseAddress, params string [] values)
 195                 {
 196                         CheckBaseAddress (baseAddress);
 197
 198                         if (values.Length != path.Count + query.Count)
 199                                 throw new FormatException (String.Format ("Template '{0}' contains {1} parameters but the argument values to bind are {2}", template, path.Count + query.Count, values.Length));
 200
 201                         int src = 0, index = 0;
 202                         StringBuilder sb = new StringBuilder (template.Length);
 203                         BindByPosition (ref src, sb, path, values, ref index);
 204                         BindByPosition (ref src, sb, query, values, ref index);
 205                         sb.Append (template.Substring (src));
 206                         return new Uri (SuffixEndRenderedUri (baseAddress.ToString ()) + TrimStartRenderedUri (sb));
 207                 }
 208
 209                 void BindByPosition (ref int src, StringBuilder sb, ReadOnlyCollection<string> names, string [] values, ref int index)
 210                 {
 211                         for (int i = 0; i < names.Count; i++) {
 212                                 int s = template.IndexOf ('{', src);
 213                                 int e = template.IndexOf ('}', s + 1);
 214                                 sb.Append (template.Substring (src, s - src));
 215                                 string value = values [index++];
 216                                 if (value == null)
 217                                         throw new FormatException (String.Format ("The argument value collection contains null at {0}", index - 1));
 218                                 sb.Append (value);
 219                                 src = e + 1;
 220                         }
 221                 }
 222
 223                 // Compare
 224
 225                 public bool IsEquivalentTo (UriTemplate other)
 226                 {
 227                         if (other == null)
 228                                 throw new ArgumentNullException ("other");
 229                         return this.template == other.template;
 230                 }
 231
 232                 // Match
 233
 234                 static readonly char [] slashSep = {'/'};
 235
 236                 public UriTemplateMatch Match (Uri baseAddress, Uri candidate)
 237                 {
 238                         CheckBaseAddress (baseAddress);
 239                         if (candidate == null)
 240                                 throw new ArgumentNullException ("candidate");
 241
 242                         var us = baseAddress.LocalPath;
 243                         if (us [us.Length - 1] != '/')
 244                                 baseAddress = new Uri (
 245                                         baseAddress.GetComponents (UriComponents.SchemeAndServer | UriComponents.Path, UriFormat.UriEscaped) + '/' + baseAddress.Query,
 246                                         baseAddress.IsAbsoluteUri ? UriKind.Absolute : UriKind.RelativeOrAbsolute
 247                                 );
 248                         if (IgnoreTrailingSlash) {
 249                                 us = candidate.LocalPath;
 250                                 if (us.Length > 0 && us [us.Length - 1] != '/')
 251                                         candidate = new Uri (
 252                                                 candidate.GetComponents (UriComponents.SchemeAndServer | UriComponents.Path, UriFormat.UriEscaped) + '/' + candidate.Query,
 253                                                 candidate.IsAbsoluteUri ? UriKind.Absolute : UriKind.RelativeOrAbsolute
 254                                         );
 255                         }
 256
 257                         int i = 0, c = 0;
 258                         UriTemplateMatch m = new UriTemplateMatch ();
 259                         m.BaseUri = baseAddress;
 260                         m.Template = this;
 261                         m.RequestUri = candidate;
 262                         var vc = m.BoundVariables;
 263
 264                         string cp = baseAddress.MakeRelativeUri (new Uri (
 265                                 baseAddress,
 266                                 candidate.GetComponents (UriComponents.PathAndQuery, UriFormat.UriEscaped)
 267                         ))
 268                                 .ToString ();
 269                         if (IgnoreTrailingSlash && cp [cp.Length - 1] == '/')
 270                                 cp = cp.Substring (0, cp.Length - 1);
 271
 272                         int tEndCp = cp.IndexOf ('?');
 273                         if (tEndCp >= 0)
 274                                 cp = cp.Substring (0, tEndCp);
 275
 276                         if (template.Length > 0 && template [0] == '/')
 277                                 i++;
 278                         if (cp.Length > 0 && cp [0] == '/')
 279                                 c++;
 280
 281                         foreach (string name in path) {
 282                                 if (name == wild_path_name) {
 283                                         vc [name] = Uri.UnescapeDataString (cp.Substring (c)); // all remaining paths.
 284                                         continue;
 285                                 }
 286                                 int n = StringIndexOf (template, '{' + name + '}', i);
 287                                 if (String.CompareOrdinal (cp, c, template, i, n - i) != 0)
 288                                         return null; // doesn't match before current template part.
 289                                 c += n - i;
 290                                 i = n + 2 + name.Length;
 291                                 int ce = cp.IndexOf ('/', c);
 292                                 if (ce < 0)
 293                                         ce = cp.Length;
 294                                 string value = cp.Substring (c, ce - c);
 295                                 string unescapedVaule = Uri.UnescapeDataString (value);
 296                                 if (value.Length == 0)
 297                                         return null; // empty => mismatch
 298                                 vc [name] = unescapedVaule;
 299                                 m.RelativePathSegments.Add (unescapedVaule);
 300                                 c += value.Length;
 301                         }
 302                         int tEnd = template.IndexOf ('?');
 303                         int wildIdx = template.IndexOf ('*');
 304                         bool wild = wildIdx >= 0;
 305                         if (tEnd < 0)
 306                                 tEnd = template.Length;
 307                         if (wild)
 308                                 tEnd = Math.Max (wildIdx - 1, 0);
 309                         if (!wild && (cp.Length - c) != (tEnd - i) ||
 310                             String.CompareOrdinal (cp, c, template, i, tEnd - i) != 0)
 311                                 return null; // suffix doesn't match
 312                         if (wild) {
 313                                 c += tEnd - i;
 314                                 foreach (var pe in cp.Substring (c).Split (slashSep, StringSplitOptions.RemoveEmptyEntries))
 315                                         m.WildcardPathSegments.Add (pe);
 316                         }
 317                         if (candidate.Query.Length == 0)
 318                                 return m;
 319
 320
 321                         string [] parameters = Uri.UnescapeDataString (candidate.Query.Substring (1)).Split ('&'); // chop first '?'
 322                         foreach (string parameter in parameters) {
 323                                 string [] pair = parameter.Split ('=');
 324                                 m.QueryParameters.Add (pair [0], pair [1]);
 325                                 if (!query_params.ContainsKey (pair [0]))
 326                                         continue;
 327                                 string templateName = query_params [pair [0]];
 328                                 vc.Add (templateName, pair [1]);
 329                         }
 330
 331                         return m;
 332                 }
 333
 334                 int StringIndexOf (string s, string pattern, int idx)
 335                 {
 336                         return CultureInfo.InvariantCulture.CompareInfo.IndexOf (s, pattern, idx, CompareOptions.OrdinalIgnoreCase);
 337                 }
 338
 339                 // Helpers
 340
 341                 void CheckBaseAddress (Uri baseAddress)
 342                 {
 343                         if (baseAddress == null)
 344                                 throw new ArgumentNullException ("baseAddress");
 345                         if (!baseAddress.IsAbsoluteUri)
 346                                 throw new ArgumentException ("baseAddress must be an absolute URI.");
 347                         if (baseAddress.Scheme == Uri.UriSchemeHttp ||
 348                             baseAddress.Scheme == Uri.UriSchemeHttps)
 349                                 return;
 350                         throw new ArgumentException ("baseAddress scheme must be either http or https.");
 351                 }
 352
 353                 ReadOnlyCollection<string> ParsePathTemplate (string template, int index, int end)
 354                 {
 355                         int widx = template.IndexOf ('*', index, end);
 356                         if (widx >= 0)
 357                                 if (widx != end - 1 && template.IndexOf ('}', widx) != end - 1)
 358                                         throw new FormatException (String.Format ("Wildcard in UriTemplate is valid only if it is placed at the last part of the path: '{0}'", template));
 359                         List<string> list = null;
 360                         int prevEnd = -2;
 361                         for (int i = index; i <= end; ) {
 362                                 i = template.IndexOf ('{', i);
 363                                 if (i < 0 || i > end)
 364                                         break;
 365                                 if (i == prevEnd + 1)
 366                                         throw new ArgumentException (String.Format ("The UriTemplate '{0}' contains adjacent templated segments, which is invalid.", template));
 367                                 int e = template.IndexOf ('}', i + 1);
 368                                 if (e < 0 || i > end)
 369                                         throw new FormatException (String.Format ("Missing '}' in URI template '{0}'", template));
 370                                 prevEnd = e;
 371                                 if (list == null)
 372                                         list = new List<string> ();
 373                                 i++;
 374                                 string name = template.Substring (i, e - i);
 375                                 string uname = name.ToUpper (CultureInfo.InvariantCulture);
 376                                 if (uname [0] == '*')
 377                                         uname = wild_path_name = uname.Substring (1);
 378                                 if (list.Contains (uname) || (path != null && path.Contains (uname)))
 379                                         throw new InvalidOperationException (String.Format ("The URI template string contains duplicate template item {{'{0}'}}", name));
 380                                 list.Add (uname);
 381                                 i = e + 1;
 382                         }
 383                         return list != null ? new ReadOnlyCollection<string> (list) : empty_strings;
 384                 }
 385
 386                 void ParseQueryTemplate (string template, int index, int end)
 387                 {
 388                         // template starts with '?'
 389                         string [] parameters = template.Substring (index + 1, end - index - 1).Split ('&');
 390                         List<string> list = null;
 391                         foreach (string parameter in parameters) {
 392                                 string [] pair = parameter.Split ('=');
 393                                 if (pair.Length != 2)
 394                                         throw new FormatException ("Invalid URI query string format");
 395                                 string pname = pair [0];
 396                                 string pvalue = pair [1];
 397                                 if (pvalue.Length >= 2 && pvalue [0] == '{' && pvalue [pvalue.Length - 1] == '}') {
 398                                         string ptemplate = pvalue.Substring (1, pvalue.Length - 2).ToUpper (CultureInfo.InvariantCulture);
 399                                         query_params.Add (pname, ptemplate);
 400                                         if (list == null)
 401                                                 list = new List<string> ();
 402                                         if (list.Contains (ptemplate) || (path != null && path.Contains (ptemplate)))
 403                                                 throw new InvalidOperationException (String.Format ("The URI template string contains duplicate template item {{'{0}'}}", pvalue));
 404                                         list.Add (ptemplate);
 405                                 }
 406                         }
 407                         query = list != null ? new ReadOnlyCollection<string> (list.ToArray ()) : empty_strings;
 408                 }
 409         }
 410 }