This projects allows you to turn a bunch of mp3s into an RSS feed formatted for the iPhone podcast app (it should work with any podcast app).

The steps are:

1. Create a directory on your webserver for example (/var/www/html/mypodcasts/)
2. Create the PHP file below in your mypodcasts directory
3. Create an .htaccess file with the following contents:

RewriteEngine On
RewriteRule (.*)\.rss mp3-to-rss.php?dirname=$1 [L]

Now, for each album/collection you want to access:

1. Create a directory of mp3s there (ie. /var/www/html/mypodcasts/themartian/)
2. Create a metadata JSON file called info.json in the mp3 directory (/var/www/html/mypodcasts/themartian/info.json), here is an example:

{"author":"Andy Weir", "title":"The Martian"}

You can now view the generated RSS feed by visiting:

http://your_domain_name/mypodcasts/themartian.rss

<?php
// url that the mp3s will be accessed at (by the podcast client)
$url = "http://yourdomain.com/mypodcasts/";
// path the mp3 directories are stored under
$mp3_dir = "/var/www/html/mypodcasts/";
 
/* Each mp3 directory must have an 'info.json' file in the format:
 
   {"author":"Peter F Hamilton","title":"The Great North Road"}
 
   You can add the following optional fields:
   summary, owner, owneremail, subtitle, description, image_file
 
   If image.jpg exists in the directory, that will be used
   as the podcast thumbnail (it can be overriden with
   image_file above)
 
 
*/
if(empty($_REQUEST['dirname']))
   dir("Missing mp3 directory");
 
$dir_name = basename($_REQUEST['dirname']);
 
if(!empty($dir_name) and is_dir($mp3_dir.$dir_name)) {
 
   $path = $mp3_dir.$dir_name."/";
   $meta_file = $path."info.json";
   $files = glob($path."*.mp3");
 
   if(!file_exists($meta_file))
   die("Missing info.json");
 
   header("Content-Type: application/rss+xml; charset=ISO-8859-1");
 
   $json = json_decode(file_get_contents($meta_file), true);
   $author = $json['author'];
   $replace_array['#AUTHOR#'] = $replace_array['#OWNER#'] = $replace_array['#OWNEREMAIL#'] = $json['author'];
   $replace_array['#TITLE#'] = $json['title'];
   $replace_array['#SUMMARY#'] = $replace_array['#DESCRIPTION#'] = $json['title']." by ".$json['author'];
   if(isset($json['summary']))
      $replace_array['#SUMMARY#'] = $json['summary'];
   $replace_array['#LINK#'] = $url.$dir_name;
   $replace_array['#IMAGE_URL#'] = $url.$dir_name."/image.jpg";
   if(isset($json['image_file']))
      $replace_array['#IMAGE_URL#'] = $url.$dir_name."/".$json['image_file'];
   $replace_array['#SUBTITLE#'] = "";
   if(isset($json['subtitle']))
      $replace_array['#SUBTITLE#'] = $json['subtitle'];
   if(isset($json['description']))
      $replace_array['#DESCRIPTION#'] = $json['description'];
   if(isset($json['owner']))
      $replace_array['#OWNER#'] = $json['owner'];
   if(isset($json['owneremail']))
      $replace_array['#OWNEREMAIL#'] = $json['owneremail'];
 
   $number = 1;
   $all_items = "";
   foreach($files as $file) {
      $size = filesize($file);
      $filename = basename($file);
   $all_items .= "
<item>
    <title>$filename</title>
    <itunes:summary>$filename</itunes:summary>
    <description>$filename</description>
    <link>$url/$dir_name/$filename</link>
    <enclosure url=\"$url/$dir_name/$filename\" type=\"audio/mpeg\" length=\"$size\"></enclosure>";
$all_items .= "<pubDate>".date("r", strtotime("1 June 2018 21:00 +$number days"))."</pubDate>";
$all_items .= "
    <itunes:author>$author</itunes:author>
    <itunes:duration>00:32:16</itunes:duration>
    <itunes:explicit>no</itunes:explicit>
    <guid>$url$dir_name/$filename</guid>
</item>";
 
      $number++;
   }
 
 
} else {
   http_response_code(404);
   die("File not found");
}
 
 
function header_update($buffer) {
   global $replace_array;
   return(str_replace(array_keys($replace_array), $replace_array, $buffer));
}
 
ob_start("header_update");
?>
<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:itunes="http://www.itunes.com/dtds/podcast-1.0.dtd" version="2.0">
<channel>
<title>#TITLE#</title>
<link>#LINK#</link>
<language>en-us</language>
<itunes:subtitle>#SUBTITLE#</itunes:subtitle>
<itunes:author>#AUTHOR#</itunes:author>
<itunes:summary>#SUMMARY#</itunes:summary>
<description>#DESCRIPTION#</description>
<itunes:owner>
    <itunes:name>#OWNER#</itunes:name>
    <itunes:email>#OWNEREMAIL#</itunes:email>
</itunes:owner>
<itunes:explicit>no</itunes:explicit>
<itunes:image href="#IMAGE_URL#" />
<itunes:category text="Arts">
     <itunes:category text="Literature"/>
</itunes:category>
<?php
 
ob_end_flush();
 
echo $all_items;
?>
 
</channel>
</rss>