add variables, fallback for timestamps

feed_generator.php

@@ -1,52 +1,91 @@
 <?php
     // work in progress!!
+    
+    // GENERAL SETTINGS -------------------------------------------------------------------
+
+    // the timezone referenced by the system for automatic timestamping.
+    // suported timezones: https://www.php.net/manual/en/timezones.php
+    $timezone = 'Asia/Jakarta';
+
+    // FEED METADATA //////////////////////////////////////////////////////////////////////
+    // certain characters must be escaped as HTML entities - note that XML only accepts five of them.
+    // reference: https://en.wikipedia.org/wiki/List_of_XML_and_HTML_character_entity_references
+    $feed_title = 'jasmine&apos;s b(rain)log | jasm1nii.xyz';
+    $feed_subtitle = 'blog articles by jasmine';
+    $blog_url = 'https://jasm1nii.xyz/blog/articles';
+    $feed_url = 'https://jasm1nii.xyz/blog/articles/articles.xml';
+    $author_name = 'jasmine';
+    $author_email = 'contact@jasm1nii.xyz';
+    $author_homepage = 'https://jasm1nii.xyz/';
+    $feed_icon = 'https://jasm1nii.xyz/assets/media/itchio-textless-white.svg';
+    $feed_logo = 'https://jasm1nii.xyz/assets/media/main/07042023-me_compressed.webp';
+
+    // PATH TO FETCH PAGES FROM ///////////////////////////////////////////////////////////
+    // __DIR__ is the directory where *this script* is located.
+    // in my case, i first need to go up two directories to get to the site root.
+    $site_root = dirname(__DIR__, 2);
+    // once i'm there, i specify the parent directory where i keep all of my blog pages.
+    $blog_root = $site_root.'/blog/articles';
+    // then i specify a pattern that matches the path of each individual page.
+    // my setup is /YYYY/MM/DD/entry.html
+    $blog_entries = $blog_root.'/*/*/*/*.html';
+
+    // ------------------------------------------------------------------------------------
 
     // create beginning of feed template.
     // reference for required elements: https://validator.w3.org/feed/docs/atom.html
     ob_start();
-    date_default_timezone_set("Asia/Jakarta");
+    date_default_timezone_set($timezone);
 
     echo    '<?xml version="1.0" encoding="utf-8"?>'
             .'<feed xmlns="http://www.w3.org/2005/Atom">'
             // optionally specify feed generator for debugging purposes.
-            .'<generator version="1.0">jasmine&apos;s PHP feed generator!! | last modified by system at ' . strtoupper(date("h:i:sa")) . ' (GMT+7)</generator>'
+            .'<generator uri="https://github.com/jasm1nii/xml-feed-generator" version="1.1">PHP feed generator by jasm1nii.xyz | last modified by the system at ' . strtoupper(date("h:i:sa")) . ' (GMT' . date('P') . ')</generator>'
-            .'<title>jasmine&apos;s b(rain)log | jasm1nii.xyz</title>'
+            .'<title>' . $feed_title . '</title>'
-            .'<subtitle>blog articles by jasmine</subtitle>'
+            .'<subtitle>' . $feed_subtitle . '</subtitle>'
-            .'<id>https://jasm1nii.xyz/blog/articles</id>';
+            .'<id>' . $blog_url . '</id>'
-    echo    '<link rel="self" href="https://jasm1nii.xyz/blog/articles/articles.xml" type="application/atom+xml"/>';
+            .'<link rel="self" href="'. $feed_url .'" type="application/atom+xml"/>'
-    echo    '<link rel="alternate" href="https://jasm1nii.xyz/blog/articles" type="text/html"/>';
+            .'<link rel="alternate" href="' . $blog_url .'" type="text/html"/>';
-
-    // define path to fetch pages from.
-    $root = dirname(__DIR__, 2);
-    $blog = $root.'/blog/articles';
 
     // force libxml to parse all HTML elements, including HTML 5. by default, the extension can only read valid HTML 4.
     libxml_use_internal_errors(true);
     
     // match feed update time with the newest entry.
-    // i'm personally not using the system modification time to avoid sending uneccessary notifications to feed readers.
+    $article_list = glob($blog_entries);
-    $article_list = glob($blog.'/*/*/*/*.html');
     $first_article = array_pop($article_list);
     $first_article_content = file_get_contents($first_article);
     $first_article_dom = new DOMDocument;
     $first_article_dom->loadHTML($first_article_content);
     $feed_updated = $first_article_dom->getElementsByTagName('time');
+    $f = 0;
     foreach ($feed_updated as $feed_updated_text) {
-        echo    '<updated>' . $feed_updated_text->getAttribute('datetime') . 'T00:00:00+07:00</updated>';
+        $feed_datetime = $feed_updated_text->getAttribute('datetime');
+        if (strlen($feed_datetime) == 10) {
+            echo    '<updated>' . $feed_datetime . 'T00:00:00' . date('P') .'</updated>';
+        }
+        elseif (strlen($feed_datetime) == 25 || strlen($feed_datetime) == 20) {
+            echo    '<updated>' . $feed_datetime .'</updated>';
+        }
+        if(++$f > 0) break;
+    }
+    // if no RFC 3339 timestamp is found, use the file creation date.
+    if (empty($feed_updated)) {
+        $first_article_created = filectime($first_article);
+        echo    '<updated>' . date(DATE_ATOM, $first_article_created) . '</updated>';
     }
 
     // rest of the template.
     echo    '<author>'
-            .'<name>jasmine</name>'
+            .'<name>' . $author_name . '</name>'
-            .'<email>contact@jasm1nii.xyz</email>'
+            .'<email>' . $author_email . '</email>'
-            .'<uri>https://jasm1nii.xyz/</uri>'
+            .'<uri>' . $author_homepage . '</uri>'
             .'</author>'
-            .'<icon>https://jasm1nii.xyz/assets/media/itchio-textless-white.svg</icon>'
+            .'<icon>' . $feed_icon . '</icon>'
-            .'<logo>https://jasm1nii.xyz/assets/media/main/07042023-me_compressed.webp</logo>';
+            .'<logo>' . $feed_logo . '</logo>';
 
     // output entries.
     $i = 0;
-    foreach (array_reverse(glob($blog.'/*/*/*/*.html')) as $article) {
+    foreach (array_reverse(glob($blog_entries)) as $article) {
         $article_content = file_get_contents($article);
         $article_dom = new DOMDocument;
         $article_dom->loadHTML($article_content);
@@ -60,16 +99,27 @@
         }
 
         // id
-        echo    '<id>https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog) . '</id>';
+        echo    '<id>https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog_root) . '</id>';
 
         // alternate link
-        echo    '<link rel="alternate" type="text/html" href="https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog) . '"/>';
+        echo    '<link rel="alternate" type="text/html" href="https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog_root) . '"/>';
 
         $updated = $article_dom->getElementsByTagName('time');
-        $t = 0;
+        $a = 0;
         foreach ($updated as $updated_text) {
-            echo    '<updated>' . $updated_text->getAttribute('datetime') . 'T00:00:00+07:00</updated>';
+            $timestamp = $updated_text->getAttribute('datetime');
-            if(++$t > 0) break;
+            if (strlen($timestamp) == 10) {
+                echo    '<updated>' . $timestamp . 'T00:00:00' . date('P'). '</updated>';
+            }
+            elseif (strlen($timestamp) == 25 || strlen($timestamp) == 20) {
+                echo    '<updated>' . $timestamp .'</updated>';
+            }
+            if(++$a > 0) break;
+        }
+        // if no RFC 3339 timestamp is found, use the file creation date.
+        if (empty($updated)) {
+            $article_created = filectime($article);
+            echo    '<updated>' . date(DATE_ATOM, $article_created) . '</updated>';
         }
 
         // summary
@@ -83,12 +133,11 @@
         }
 
         // content
-        // HTML entities must be escaped - note that XML only defines five of them.
-        // reference: https://en.wikipedia.org/wiki/List_of_XML_and_HTML_character_entity_references
         $content_class = 'e-content';
         $content = $x->query("//*[@class='" . $content_class . "']");
         if ($content->length > 0) {
-            echo    '<content type="html">' . preg_replace('/\s\s+/', ' ',(substr($content->item(0)->nodeValue,0,500))) . '... (&lt;a href="https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog) . '"&gt;read more&lt;/a&gt;)' . '</content>';
+            // strip line breaks and output a maximum of 500 characters.
+            echo    '<content type="html">' . preg_replace('/\s\s+/', ' ',(substr($content->item(0)->nodeValue,0,500))) . '... (&lt;a href="https://jasm1nii.xyz/blog/articles/' . ltrim($article, $blog_root) . '"&gt;read more&lt;/a&gt;)' . '</content>';
         } else {
             // fallback for older markup
             $content_class = 'entry';
@@ -99,11 +148,13 @@
         }
 
         echo    '</entry>';
+
+        // add no more than 10 entries.
         if(++$i > 9) break;
     }
     echo '</feed>';
 
     $xml_str = ob_get_contents();
     ob_end_clean();
-    file_put_contents($blog.'/articles.xml', $xml_str);
+    file_put_contents($blog_root.'/articles.xml', $xml_str);
 ?>