2 // Rss20ItemFormatter.cs
5 // Atsushi Enomoto <atsushi@ximian.com>
7 // Copyright (C) 2007 Novell, Inc (http://www.novell.com)
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:
17 // The above copyright notice and this permission notice shall be
18 // included in all copies or substantial portions of the Software.
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.
29 using System.Collections.Generic;
30 using System.Collections.ObjectModel;
31 using System.Globalization;
34 using System.Runtime.Serialization;
37 using System.Xml.Schema;
38 using System.Xml.Serialization;
40 namespace System.ServiceModel.Syndication
42 static class XmlReaderExtensions
44 public static bool IsTextNode (this XmlReader r)
47 case XmlNodeType.Text:
48 case XmlNodeType.CDATA:
49 case XmlNodeType.Whitespace:
50 case XmlNodeType.SignificantWhitespace:
57 [XmlRoot ("item", Namespace = "")]
58 public class Rss20ItemFormatter : SyndicationItemFormatter, IXmlSerializable
60 const string AtomNamespace ="http://www.w3.org/2005/Atom";
62 bool ext_atom_serialization, preserve_att_ext = true, preserve_elem_ext = true;
65 public Rss20ItemFormatter ()
67 ext_atom_serialization = true;
70 public Rss20ItemFormatter (SyndicationItem itemToWrite)
71 : this (itemToWrite, true)
75 public Rss20ItemFormatter (SyndicationItem itemToWrite, bool serializeExtensionsAsAtom)
78 ext_atom_serialization = serializeExtensionsAsAtom;
81 public Rss20ItemFormatter (Type itemTypeToCreate)
83 if (itemTypeToCreate == null)
84 throw new ArgumentNullException ("itemTypeToCreate");
85 item_type = itemTypeToCreate;
88 public bool SerializeExtensionsAsAtom {
89 get { return ext_atom_serialization; }
90 set { ext_atom_serialization = value; }
93 protected Type ItemType {
94 get { return item_type; }
97 public bool PreserveAttributeExtensions {
98 get { return preserve_att_ext; }
99 set { preserve_att_ext = value; }
102 public bool PreserveElementExtensions {
103 get { return preserve_elem_ext; }
104 set { preserve_elem_ext = value; }
107 public override string Version {
108 get { return "Rss20"; }
111 protected override SyndicationItem CreateItemInstance ()
113 return new SyndicationItem ();
116 public override bool CanRead (XmlReader reader)
119 throw new ArgumentNullException ("reader");
120 reader.MoveToContent ();
121 return reader.IsStartElement ("item", String.Empty);
124 public override void ReadFrom (XmlReader reader)
126 if (!CanRead (reader))
127 throw new XmlException (String.Format ("Element '{0}' in namespace '{1}' is not accepted by this syndication formatter", reader.LocalName, reader.NamespaceURI));
128 ReadXml (reader, true);
131 public override void WriteTo (XmlWriter writer)
133 WriteXml (writer, true);
136 void IXmlSerializable.ReadXml (XmlReader reader)
138 ReadXml (reader, false);
141 void IXmlSerializable.WriteXml (XmlWriter writer)
143 WriteXml (writer, false);
146 XmlSchema IXmlSerializable.GetSchema ()
153 void ReadXml (XmlReader reader, bool fromSerializable)
156 throw new ArgumentNullException ("reader");
158 SetItem (CreateItemInstance ());
160 reader.MoveToContent ();
162 if (PreserveAttributeExtensions && reader.MoveToFirstAttribute ()) {
164 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
166 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, Item, Version))
167 Item.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
168 } while (reader.MoveToNextAttribute ());
171 reader.ReadStartElement ();
173 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
174 if (reader.NodeType != XmlNodeType.Element)
175 throw new XmlException ("Only element node is expected under 'item' element");
176 if (reader.NamespaceURI == String.Empty)
177 switch (reader.LocalName) {
179 Item.Title = ReadTextSyndicationContent (reader);
182 SyndicationLink l = Item.CreateLink ();
183 ReadLink (reader, l);
187 Item.Summary = ReadTextSyndicationContent (reader);
190 SyndicationPerson p = Item.CreatePerson ();
191 ReadPerson (reader, p);
192 Item.Authors.Add (p);
195 SyndicationCategory c = Item.CreateCategory ();
196 ReadCategory (reader, c);
197 Item.Categories.Add (c);
199 // case "comments": // treated as extension ...
201 l = Item.CreateLink ();
202 ReadEnclosure (reader, l);
206 Item.Id = reader.ReadElementContentAsString ();
207 if (reader.GetAttribute ("isPermaLink") == "true")
208 Item.AddPermalink (CreateUri (Item.Id));
211 Item.PublishDate = FromRFC822DateString (reader.ReadElementContentAsString ());
214 Item.SourceFeed = new SyndicationFeed ();
215 ReadSourceFeed (reader, Item.SourceFeed);
218 else if (SerializeExtensionsAsAtom && reader.NamespaceURI == AtomNamespace) {
219 switch (reader.LocalName) {
221 SyndicationPerson p = Item.CreatePerson ();
222 ReadPersonAtom10 (reader, p);
223 Item.Contributors.Add (p);
226 Item.LastUpdatedTime = XmlConvert.ToDateTimeOffset (reader.ReadElementContentAsString ());
229 Item.Copyright = ReadTextSyndicationContent (reader);
232 if (reader.GetAttribute ("src") != null) {
233 Item.Content = new UrlSyndicationContent (CreateUri (reader.GetAttribute ("src")), reader.GetAttribute ("type"));
237 switch (reader.GetAttribute ("type")) {
241 Item.Content = ReadTextSyndicationContent (reader);
244 SyndicationContent content;
245 if (!TryParseContent (reader, Item, reader.GetAttribute ("type"), Version, out content))
246 Item.Content = new XmlSyndicationContent (reader);
251 if (!TryParseElement (reader, Item, Version)) {
252 if (PreserveElementExtensions)
253 // FIXME: what to specify for maxExtensionSize
254 LoadElementExtensions (reader, Item, int.MaxValue);
260 reader.ReadEndElement (); // </item>
263 TextSyndicationContent ReadTextSyndicationContent (XmlReader reader)
265 TextSyndicationContentKind kind = TextSyndicationContentKind.Plaintext;
266 switch (reader.GetAttribute ("type")) {
268 kind = TextSyndicationContentKind.Html;
271 kind = TextSyndicationContentKind.XHtml;
274 string text = reader.ReadElementContentAsString ();
275 TextSyndicationContent t = new TextSyndicationContent (text, kind);
279 void ReadCategory (XmlReader reader, SyndicationCategory category)
281 if (reader.MoveToFirstAttribute ()) {
283 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
285 if (reader.NamespaceURI == String.Empty) {
286 switch (reader.LocalName) {
288 category.Scheme = reader.Value;
292 if (PreserveAttributeExtensions)
293 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, category, Version))
294 category.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
295 } while (reader.MoveToNextAttribute ());
296 reader.MoveToElement ();
299 if (!reader.IsEmptyElement) {
301 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
302 if (reader.IsTextNode ())
303 category.Name += reader.Value;
304 else if (!TryParseElement (reader, category, Version)) {
305 if (PreserveElementExtensions)
306 // FIXME: what should be used for maxExtenswionSize
307 LoadElementExtensions (reader, category, int.MaxValue);
314 reader.Read (); // </category> or <category ... />
317 // SyndicationLink.CreateMediaEnclosureLink() is almost
318 // useless here since it cannot handle extension attributes
319 // in straightforward way (it I use it, I have to iterate
320 // attributes twice just to read extensions).
321 void ReadEnclosure (XmlReader reader, SyndicationLink link)
323 link.RelationshipType = "enclosure";
325 if (PreserveAttributeExtensions && reader.MoveToFirstAttribute ()) {
327 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
329 if (reader.NamespaceURI == String.Empty) {
330 switch (reader.LocalName) {
332 link.Uri = CreateUri (reader.Value);
335 link.MediaType = reader.Value;
338 link.Length = XmlConvert.ToInt64 (reader.Value);
342 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, link, Version))
343 link.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
344 } while (reader.MoveToNextAttribute ());
345 reader.MoveToElement ();
348 // Actually .NET fails to read extension here.
349 if (!reader.IsEmptyElement) {
351 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
352 if (!TryParseElement (reader, link, Version)) {
353 if (PreserveElementExtensions)
354 // FIXME: what should be used for maxExtenswionSize
355 LoadElementExtensions (reader, link, int.MaxValue);
361 reader.Read (); // </enclosure> or <enclosure ... />
364 void ReadLink (XmlReader reader, SyndicationLink link)
366 if (PreserveAttributeExtensions && reader.MoveToFirstAttribute ()) {
368 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
370 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, link, Version))
371 link.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
372 } while (reader.MoveToNextAttribute ());
373 reader.MoveToElement ();
376 if (!reader.IsEmptyElement) {
379 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
380 if (reader.IsTextNode ())
382 else if (!TryParseElement (reader, link, Version)) {
383 if (PreserveElementExtensions)
384 // FIXME: what should be used for maxExtenswionSize
385 LoadElementExtensions (reader, link, int.MaxValue);
391 link.Uri = CreateUri (url);
393 reader.Read (); // </link> or <link ... />
396 void ReadPerson (XmlReader reader, SyndicationPerson person)
398 if (PreserveAttributeExtensions && reader.MoveToFirstAttribute ()) {
400 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
402 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, person, Version))
403 person.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
404 } while (reader.MoveToNextAttribute ());
405 reader.MoveToElement ();
408 if (!reader.IsEmptyElement) {
410 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
411 if (reader.IsTextNode ())
412 person.Email += reader.Value;
413 else if (!TryParseElement (reader, person, Version)) {
414 if (PreserveElementExtensions)
415 // FIXME: what should be used for maxExtenswionSize
416 LoadElementExtensions (reader, person, int.MaxValue);
423 reader.Read (); // end element or empty element
426 // copied from Atom10ItemFormatter
427 void ReadPersonAtom10 (XmlReader reader, SyndicationPerson person)
429 if (reader.MoveToFirstAttribute ()) {
431 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
433 if (!TryParseAttribute (reader.LocalName, reader.NamespaceURI, reader.Value, person, Version) && PreserveAttributeExtensions)
434 person.AttributeExtensions.Add (new XmlQualifiedName (reader.LocalName, reader.NamespaceURI), reader.Value);
435 } while (reader.MoveToNextAttribute ());
436 reader.MoveToElement ();
439 if (!reader.IsEmptyElement) {
441 for (reader.MoveToContent (); reader.NodeType != XmlNodeType.EndElement; reader.MoveToContent ()) {
442 if (reader.NodeType == XmlNodeType.Element && reader.NamespaceURI == AtomNamespace) {
443 switch (reader.LocalName) {
445 person.Name = reader.ReadElementContentAsString ();
448 person.Uri = reader.ReadElementContentAsString ();
451 person.Email = reader.ReadElementContentAsString ();
455 if (!TryParseElement (reader, person, Version)) {
456 if (PreserveElementExtensions)
457 // FIXME: what should be used for maxExtenswionSize
458 LoadElementExtensions (reader, person, int.MaxValue);
464 reader.Read (); // end element or empty element
467 void ReadSourceFeed (XmlReader reader, SyndicationFeed feed)
469 if (reader.MoveToFirstAttribute ()) {
471 if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
473 if (reader.NamespaceURI == String.Empty) {
474 switch (reader.LocalName) {
476 feed.Links.Add (new SyndicationLink (CreateUri (reader.Value)));
480 } while (reader.MoveToNextAttribute ());
481 reader.MoveToElement ();
484 if (!reader.IsEmptyElement) {
487 while (reader.NodeType != XmlNodeType.EndElement) {
488 if (reader.IsTextNode ())
489 title += reader.Value;
491 reader.MoveToContent ();
493 feed.Title = new TextSyndicationContent (title);
495 reader.Read (); // </source> or <source ... />
498 Uri CreateUri (string uri)
500 return new Uri (uri, UriKind.RelativeOrAbsolute);
505 void WriteXml (XmlWriter writer, bool writeRoot)
508 throw new ArgumentNullException ("writer");
510 throw new InvalidOperationException ("Syndication item must be set before writing");
513 writer.WriteStartElement ("item");
515 if (Item.BaseUri != null)
516 writer.WriteAttributeString ("xml:base", Item.BaseUri.ToString ());
518 WriteAttributeExtensions (writer, Item, Version);
520 if (Item.Id != null) {
521 writer.WriteStartElement ("guid");
522 writer.WriteAttributeString ("isPermaLink", "false");
523 writer.WriteString (Item.Id);
524 writer.WriteEndElement ();
527 if (Item.Title != null) {
528 writer.WriteStartElement ("title");
529 writer.WriteString (Item.Title.Text);
530 writer.WriteEndElement ();
533 foreach (SyndicationPerson author in Item.Authors)
534 if (author != null) {
535 writer.WriteStartElement ("author");
536 WriteAttributeExtensions (writer, author, Version);
537 writer.WriteString (author.Email);
538 WriteElementExtensions (writer, author, Version);
539 writer.WriteEndElement ();
541 foreach (SyndicationCategory category in Item.Categories)
542 if (category != null) {
543 writer.WriteStartElement ("category");
544 if (category.Scheme != null)
545 writer.WriteAttributeString ("domain", category.Scheme);
546 WriteAttributeExtensions (writer, category, Version);
547 writer.WriteString (category.Name);
548 WriteElementExtensions (writer, category, Version);
549 writer.WriteEndElement ();
552 if (Item.Content != null) {
553 Item.Content.WriteTo (writer, "description", String.Empty);
554 } else if (Item.Summary != null)
555 Item.Summary.WriteTo (writer, "description", String.Empty);
556 else if (Item.Title == null) { // according to the RSS 2.0 spec, either of title or description must exist.
557 writer.WriteStartElement ("description");
558 writer.WriteEndElement ();
561 foreach (SyndicationLink link in Item.Links)
562 switch (link.RelationshipType) {
564 writer.WriteStartElement ("enclosure");
565 if (link.Uri != null)
566 writer.WriteAttributeString ("uri", link.Uri.ToString ());
567 if (link.Length != 0)
568 writer.WriteAttributeString ("length", XmlConvert.ToString (link.Length));
569 if (link.MediaType != null)
570 writer.WriteAttributeString ("type", link.MediaType);
571 WriteAttributeExtensions (writer, link, Version);
572 WriteElementExtensions (writer, link, Version);
573 writer.WriteEndElement ();
576 writer.WriteStartElement ("link");
577 WriteAttributeExtensions (writer, link, Version);
578 writer.WriteString (link.Uri != null ? link.Uri.ToString () : String.Empty);
579 WriteElementExtensions (writer, link, Version);
580 writer.WriteEndElement ();
584 if (Item.SourceFeed != null) {
585 writer.WriteStartElement ("source");
586 if (Item.SourceFeed.Links.Count > 0) {
587 Uri u = Item.SourceFeed.Links [0].Uri;
588 writer.WriteAttributeString ("url", u != null ? u.ToString () : String.Empty);
590 writer.WriteString (Item.SourceFeed.Title != null ? Item.SourceFeed.Title.Text : String.Empty);
591 writer.WriteEndElement ();
594 if (!Item.PublishDate.Equals (default (DateTimeOffset))) {
595 writer.WriteStartElement ("pubDate");
596 writer.WriteString (ToRFC822DateString (Item.PublishDate));
597 writer.WriteEndElement ();
600 if (SerializeExtensionsAsAtom) {
601 foreach (SyndicationPerson contributor in Item.Contributors) {
602 if (contributor != null) {
603 writer.WriteStartElement ("contributor", AtomNamespace);
604 WriteAttributeExtensions (writer, contributor, Version);
605 writer.WriteElementString ("name", AtomNamespace, contributor.Name);
606 writer.WriteElementString ("uri", AtomNamespace, contributor.Uri);
607 writer.WriteElementString ("email", AtomNamespace, contributor.Email);
608 WriteElementExtensions (writer, contributor, Version);
609 writer.WriteEndElement ();
613 if (!Item.LastUpdatedTime.Equals (default (DateTimeOffset))) {
614 writer.WriteStartElement ("updated", AtomNamespace);
615 // FIXME: how to handle offset part?
616 writer.WriteString (XmlConvert.ToString (Item.LastUpdatedTime.DateTime, XmlDateTimeSerializationMode.Local));
617 writer.WriteEndElement ();
620 if (Item.Copyright != null)
621 Item.Copyright.WriteTo (writer, "rights", AtomNamespace);
623 if (Item.Content != null)
624 Item.Content.WriteTo (writer, "content", AtomNamespace);
628 WriteElementExtensions (writer, Item, Version);
631 writer.WriteEndElement ();
634 // FIXME: DateTimeOffset.ToString() needs another overload.
635 // When it is implemented, just remove ".DateTime" parts below.
636 string ToRFC822DateString (DateTimeOffset date)
638 switch (date.DateTime.Kind) {
639 case DateTimeKind.Utc:
640 return date.DateTime.ToString ("ddd, dd MMM yyyy HH:mm:ss 'Z'", DateTimeFormatInfo.InvariantInfo);
641 case DateTimeKind.Local:
642 StringBuilder sb = new StringBuilder (date.DateTime.ToString ("ddd, dd MMM yyyy HH:mm:ss zzz", DateTimeFormatInfo.InvariantInfo));
643 sb.Remove (sb.Length - 3, 1);
644 return sb.ToString (); // remove ':' from +hh:mm
646 return date.DateTime.ToString ("ddd, dd MMM yyyy HH:mm:ss", DateTimeFormatInfo.InvariantInfo);
650 string [] rfc822formats = new string [] {
651 "ddd, dd MMM yyyy HH:mm:ss 'Z'",
652 "ddd, dd MMM yyyy HH:mm:ss zzz",
653 "ddd, dd MMM yyyy HH:mm:ss"};
655 // FIXME: DateTimeOffset is still incomplete. When it is done,
656 // simplify the code.
657 DateTimeOffset FromRFC822DateString (string s)
659 return XmlConvert.ToDateTimeOffset (s, rfc822formats);