Question

I need to add a new item element to my RSS file, via PHP, without just generating the RSS from PHP. I know this will require removing older items, to match the number that I want displayed, but I don’t know how to add them to the file in the first place.

My code looks somewhat like this:

<rss version="2.0">
  <channel>
    <title>My Site Feed</title>
    <link>http://www.mysitethathasfeed.com/feed/</link>
    <description>
        A nice site that features a feed.
    </description>
    <item>
        <title>Launched!</title>
        <link>http://www.mysitethathasfeed.com/feed/view.php?ID=launched</link>
        <description>
           We just launched the site! Come join the celebration!
        </description>
    </item>
  </channel>
</rss>

Answer 1

Extending the answer from Kyle (oh OOP inheritence), and references from the PHP Manual

<?php

$rss = file_get_contents('feed.rss');
$dom = new DOMDocument();
$dom->loadXML($rss);

// should have only 1 node in the list
$nodeList = $dom->getElementsByTagName('channel');

// assuming there's only 1 channel tag in the RSS file:
$nChannel = $nodeList->item(0);

// now create the new item
$newNode = $dom->createElement('item');
$newNode->appendChild($dom->createElement('title', 'a new title post'));
$newNode->appendChild($dom->createElement('link', 'http://www.mysitethathasfeed.com/feed/view.php?ID=launched'));
$newNode->appendChild($dom->createElement('description', 'This is the 2nd post of our feed.'));

// add item to channel
$nChannel->appendChild($newNode);
$rss = $dom->saveXML();
file_put_contents('feed.rss', $rss);