6CC001 Workshop - week 06

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Today let’s play with RSS feeds. There are 2 things you can do:

• Consume an existing third-party feed
• Create your own feed, for other users to consume

Consume an existing third-party feed

Since PHP 5, consuming an XML file (remember that’s all an RSS feed is!) couldn’t be more simple:

  $feed_url = "http://newsrss.bbc.co.uk/rss/newsonline_uk_edition/front_page/rss.xml";

  // Get data from feed file
  $response = file_get_contents($feed_url);
    
  // Insert XML into structure
  $xml = simplexml_load_string($response); 

  // Browse structure
  foreach($xml->channel->item as $one_item)
    echo $one_item->title."<BR>"; 

First you load the content of the remote file into a variable, using the file_get_contents function.

Then you concert this big blob of data into a more friendly, loop-able structured object, using the simplexml_load_string function.

And finally, you loop through your object and display the data on the screen. This example only displays the title of the different articles. Note: You might want to improve this part (items in a list, clickable links etc…)

Create your own feed, for other users to consume

  // Connect to database
  
  // Get latest items from db
  $sql = "SELECT title FROM messages ORDER BY date_added DESC limit 0,10";
  $rst = mysql_query($sql);
  
  // Loop through data and build feed items
  $items = "";
  while($a_row = mysql_fetch_assoc($rst))
  {
    $items.= "<item>";
    $items.= "  <title>{$rst['title']}</title>";
    $items.= "  <link>http://www.dude.com/</link>";
    $items.= "  <description>A cool article</description>";
    $items.= "</item>"; 
  }
  
  // Build feed text
  $feed = "<?xml version=\"1.0\"?>";
  $feed.= "<rss version=\"2.0\">";
  $feed.= "  <channel>";
  $feed.= "    <title>My cool feed</title>";
  $feed.= "    <link>http://www.dude.com/</link>";
  $feed.= "    <description>A cool feed</description>";
  $feed.= "    $items";
  $feed.= "  </channel>";
  $feed.= "</rss>";
  
  // Display feed text
  echo $feed;