5.4 KiB
RSS Feed
Introduction
Generating RSS/Atom-feeds is a matter of rendering a [api:SS_List] through
the [api:RSSFeed] class.
The [api:RSSFeed] class doesn't limit you to generating article based feeds,
it is just as easy to create a feed of your current staff members, comments or
any other custom [api:DataObject] subclasses you have defined. The only
logical limitation here is that every item in the RSS-feed should be accessible
through a URL on your website, so its advisable to just create feeds from sub
classes of [api:SiteTree].
If you wish to generate an RSS feed for [api:DataObject] instances, ensure they
define an AbsoluteLink() method.
Usage
:::php
RSSFeed::linkToFeed($link, $title)
This line should go in your [api:Controller] subclass in the action you want
to include the HTML link.
:::php
$feed = new RSSFeed(
$list,
$link,
$title,
$description,
$titleField,
$descriptionField,
$authorField
);
Creates a new [api:RSSFeed] instance to be returned. The arguments notify
SilverStripe what values to include in the feed.
Examples
Showing latest blog posts
:::php
class Page_Controller extends ContentController {
private static $allowed_actions = array('rss');
public function init() {
// linkToFeed will add an appropriate HTML link tag to the website
// <head> tag to notify web browsers that an RSS feed is available
// for this page. You can include as many feeds on the page as you
// wish as long as each as a different link. For example:
// ('blog/rss', 'staff/rss').
//
// In this example $this->Link("rss") refers to the *rss* function
// we define below.
RSSFeed::linkToFeed($this->Link("rss"), "RSS feed of this blog");
parent::init();
}
public function rss() {
// Creates a new RSS Feed list
$rss = new RSSFeed(
$list = $this->getBlogPosts(), // an SS_List containing your feed items
$link = $this->Link("rss"), // a HTTP link to this feed
$title = "My feed", // title for this feed, displayed in RSS readers
$description = "This is an example feed." // description
);
// Outputs the RSS feed to the user.
return $rss->outputToBrowser();
}
public function getBlogPosts() {
return BlogPage::get()->limit(10);
}
}
Showing the 10 most recently updated pages
You can use [api:RSSFeed] to easily create a feed showing your latest Page
updates. Update mysite/code/Page.php to something like this:
:::php
<?php
class Page extends SiteTree {}
class Page_Controller extends ContentController {
private static $allowed_actions = array('rss');
public function init() {
RSSFeed::linkToFeed($this->Link() . "rss", "10 Most Recently Updated Pages");
parent::init();
}
public function rss() {
$rss = new RSSFeed($this->LatestUpdates(), $this->Link(), "10 Most Recently Updated Pages", "Shows a list of the 10 most recently updated pages.");
return $rss->outputToBrowser();
}
public function LatestUpdates() {
return Page::get()->sort("LastEdited", "DESC")->limit(10);
}
}
Rendering DataObjects in a RSSFeed
DataObjects can be rendered in the feed as well, however, since they aren't explicitly
[api:SiteTree] subclasses we need to include a function AbsoluteLink to allow the
RSS feed to link through to the item.
If the items are all displayed on a single page you may simply hard code the link to point to a particular page.
Take an example, we want to create an RSS feed of all the Students, a DataObject we defined in the fifth tutorial.
:::php
<?php
class Student extends DataObject {
public function AbsoluteLink() {
// see tutorial 5, students are assigned a project, so the 'link'
// to view the student is based on their projects link.
return $this->Project()->AbsoluteLink();
}
}
Then update the Page_Controller class in mysite/code/Page.php to include an RSSFeed for all the students as we've seen before.
:::php
class Page_Controller extends ContentController {
private static $allowed_actions = array('students');
public function init() {
RSSFeed::linkToFeed($this->Link("students"), "Students feed");
parent::init();
}
public function students() {
$rss = new RSSFeed(
$list = $this->getStudents(),
$link = $this->Link("students"),
$title = "Students feed"
);
return $rss->outputToBrowser();
}
public function getStudents() {
return Student::get()->sort("Created", "DESC")->limit(10);
}
}
Customizing the RSS Feed template
The default template used is framework/templates/RSSFeed.ss and includes
displaying titles and links to the content. If you have a particular need
for customizing the XML produced (say for additional meta data) use setTemplate.
Taking that last example, we would rewrite the students function to include a unique template (write your own XML in themes/yourtheme/templates/Students.ss)
:::php
public function students() {
$rss = new RSSFeed(
$list = $this->getStudents(),
$link = $this->Link("students"),
$title = "Students feed"
);
$rss->setTemplate('Students');
return $rss->outputToBrowser();
}
External Sources
[api:RSSFeed] only creates feeds from your own data. We've included the SimplePie RSS-parser for
accessing feeds from external sources.
Related
API Documentation
[api:RSSFeed]