 
Create an RSS 2.0 document from a template. RSS 2.0 is an update of RSS 0.91, and so does not follow the RDF approach taken by RSS 1.0. After RSS 0.91 and RSS 1.0, it is the third most popular RSS format. You can find the spec for RSS 2.0 at http://blogs.law.harvard.edu/tech/rss. It is similar to RSS 0.91, but offers some clarifications and additional elements. The following, news.xml, is a minimal example of RSS 2.0: <rss version="2.0"> <channel> <title>Wy'east Communications</title> <link>http://www.wyeast.net</link> <description> Wy'east Communications is an XML consultancy.</description> <item> <title>Legend of Wy'east</title> <link>http://www.wyeast.net/wyeast.html</link> <description>The Native American story behind the name Wy'east.</description> </item> </channel> </rss>
Like RSS 0.91, RSS 2.0 doesn't declare a namespace for its own elements. Also like 0.91, rss is the document element. It must have a version attribute with a value of 2.0. The channel element is required, as are its children title, link, and description. The language element is required as a child of channel by 0.91, but under 2.0 it is optional. The image element is also required by 0.91; it's optional under 2.0. Table 6-2 compares the required and optional elements of channel in 2.0 and 0.91. The purpose of each is briefly described. Table 6-2. Child elements of channel in RSS 2.0 and RSS 0.91| Element | Purpose | RSS 2.0 | RSS 0.91 |
|---|
| title | Title of channel | Required | Required | | link | Link to channel | Required | Required | | description | Description of channel | Required | Required | | language | Language code for channel | Optional | Required | | image | Image that represents the channel (required children url, title, and link; optional children description, width, and height) | Optional | Required | | copyright | Copyright notice for the channel | Optional | Optional | | managingEditor | Email address of managing editor | Optional | Optional | | webMaster | Email address of webmaster | Optional | Optional | | pubDate | Publication date of channel in RFC 822 format, Sat, 01 Jan 05 00:00:27 PST; though not specified in RFC 822, a four-digit year is allowed (see http://www.ietf.org/rfc/rfc822.txt) | Optional | Optional | | lastBuildDate | Last time channel content changed in RFC 822 format, Sat, 01 Jan 05 00:00:27 PST; though not specified in RFC 822, a four-digit year is allowed (see http://www.ietf.org/rfc/rfc822.txt) | Optional | Optional | | rating | Platform for Internet Content Selection (PICS) rating (http://www.w3.org/PICS/) | Optional | Optional | | docs | Documentation for the RSS format used by channel | Optional | Optional | | textInput | A text input box for the channel, such as a search box (required children include title, description, name, and link) | Optional | Optional | | skipDays | Days to skip reading channel | Optional | Optional | | skipHours | Hours to skip reading channel | Optional | Optional | | category | One or more channel categories | Optional | N/A | | generator | Name of generator program | Optional | N/A | | cloud | Specifies a protocol for publishing and subscribing to feeds | Optional | N/A | | ttl | Time to live in minutes | Optional | N/A |
Under the item element in RSS 2.0, a description element can contain entity-encoded HTML. In other words, it can hold an article or story in itself, written in HTML (with & for & and < for <). Table 6-3 compares the 0.91 and 2.0 children of item. Table 6-3. Child elements of item in RSS 2.0 and RSS 0.91| Element | Purpose | RSS 2.0 | RSS 0.91 |
|---|
| title | Title of item | Optional /Required | Required | | link | Link to item | Optional /Required | Required | | description | Description of item | Optional /Required | Optional | | author | Email address of author of item | Optional | N/A | | category | One or more item categories (optional attribute domain) | Optional | N/A | | comments | URL for comment page for item | Optional | N/A | | enclosure | Describes an object attached to item (required attributes url, length, and type) | Optional | N/A | | guid | Globally unique identifier | Optional | N/A | | pubDate | Publication date in RFC 822 format | Optional | N/A | | source | RSS channel the item came from (required attribute url) | Optional | N/A |
An item element may represent a story such as an article from a newspaper or a magazine. In such a case, the item's description child should contain a synopsis of the story, with a URI in the link element pointing to the full story. On the other hand, an item may also contain a complete story. In this case, the description child of item will contain the text of the whole story (which may be entity-encoded HTML), so the link and title children of item don't have to be included. Though all elements of item are optional in 2.0, at least one title or description must be present.  | RSS 2.0 restricts the first non-whitespace characters in the content of link and url elements. This content must begin with a URI scheme registered at IANA (http://www.iana.org/assignments/uri-schemes), such as ftp://, http://, https://, mailto:, or news://. RSS 0.91 allows only http:// and ftp://. |
|
6.5.1 See Also |
