Add support for RSS1.0 feeds

application/forms/FeedForm.php

@@ -82,7 +82,8 @@ protected function assemble(): void
             ),
             'multiOptions' => [
                 'auto' => $this->translate('Determine automatically'),
-                'rss' => $this->translate('RSS'),
+                'rss' => $this->translate('RSS2.0'),
+                'rss1.0' => $this->translate('RSS1.0'),
                 'atom' => $this->translate('Atom'),
                 'jsonfeed' => $this->translate('JSONfeed'),
             ],

library/Feeds/FeedReader.php

@@ -6,6 +6,7 @@
 use Icinga\Module\Feeds\Parser\FeedType;
 use Icinga\Module\Feeds\Parser\JsonfeedParser;
 use Icinga\Module\Feeds\Parser\RSSParser;
+use Icinga\Module\Feeds\Parser\RSS1Parser;
 use Icinga\Module\Feeds\Parser\Result\Feed;
 
 use Icinga\Application\Config;
@@ -78,7 +79,13 @@ protected function parse(string $rawResponse): ?Feed
                 try {
                     return RSSParser::parse($rawResponse);
                 } catch (Exception $ex) {
-                    // Not an RSS feed
+                    // Not an RSS 2.0 feed
+                }
+
+                try {
+                    return RSS1Parser::parse($rawResponse);
+                } catch (Exception $ex) {
+                    // Not an RSS 1.0 feed
                 }
 
                 try {
@@ -96,6 +103,8 @@ protected function parse(string $rawResponse): ?Feed
                 throw new Exception('Unsupported feed type or invalid data in feed');
             case FeedType::RSS:
                 return RSSParser::parse($rawResponse);
+            case FeedType::RSS1:
+                return RSS1Parser::parse($rawResponse);
             case FeedType::Atom:
                 return AtomParser::parse($rawResponse);
             case FeedType::Jsonfeed:

library/Feeds/Parser/FeedType.php

@@ -13,6 +13,7 @@ enum FeedType: int
     case RSS = 1;
     case Atom = 2;
     case Jsonfeed = 3;
+    case RSS1 = 4;
 
     /**
      * display returns the string representation of the type
@@ -22,6 +23,7 @@ public function display(): string
         return match ($this) {
             self::Auto => 'auto',
             self::RSS => 'rss',
+            self::RSS1 => 'rss1.0',
             self::Atom => 'atom',
             self::Jsonfeed => 'jsonfeed',
             default => throw new Exception('Unreachable code')
@@ -36,6 +38,7 @@ public static function fromDisplay(string $display): static
         return match ($display) {
             'auto' => self::Auto,
             'rss' => self::RSS,
+            'rss1.0' => self::RSS1,
             'atom' => self::Atom,
             'jsonfeed' => self::Jsonfeed,
             default => throw new Exception('Invalid FeedType')

library/Feeds/Parser/RSS1Parser.php

@@ -0,0 +1,152 @@
+<?php
+
+namespace Icinga\Module\Feeds\Parser;
+
+use Icinga\Module\Feeds\Parser\Result\Feed;
+use Icinga\Module\Feeds\Parser\Result\FeedItem;
+
+use SimpleXMLElement;
+use Exception;
+use DateTime;
+use DateTimeInterface;
+
+/**
+ * RSS1Parser is used to parse RSS 1.0 feeds
+ */
+class RSS1Parser
+{
+    /**
+     * parse tries to parse the given string into a Feed object
+     */
+    public static function parse(string $raw): Feed
+    {
+        $xmlElement = new SimpleXMLElement($raw);
+        $xmlElement->registerXPathNamespace('rss', 'http://purl.org/rss/1.0/');
+        $xmlElement->registerXPathNamespace('dc', 'http://purl.org/dc/elements/1.1/');
+
+        if ($xmlElement->getName() !== 'RDF') {
+            throw new Exception('Invalid RSS1.0-Feed');
+        }
+
+        $xmlElement->rewind();
+
+        return static::parseFeed($xmlElement);
+    }
+
+    protected static function parseFeed(SimpleXMLElement $xml): Feed
+    {
+        $feed = new Feed();
+
+        foreach ($xml->getChildren() as $elementName => $xmlItemElement) {
+            switch ($elementName) {
+                case 'title':
+                    $feed->title = $xmlItemElement->__toString();
+                    break;
+                case 'link':
+                    $feed->link = $xmlItemElement->__toString();
+                    break;
+                case 'description':
+                    $feed->description = $xmlItemElement->__toString();
+                    break;
+                case 'image':
+                    foreach ($xmlItemElement as $imgTagName => $imgElement) {
+                        if ($imgTagName === 'url') {
+                            $feed->image = $imgElement->__toString();
+                            break;
+                        }
+                    }
+                    break;
+            }
+        }
+
+        $items = $xml->xpath('//rss:item');
+
+        foreach ($items as $xmlItemElement) {
+            $item = static::parseItem($feed, $xmlItemElement);
+            $feed->addItem($item);
+        }
+
+        return $feed;
+    }
+
+    protected static function parseDateTime(string $dateStr): ?DateTime
+    {
+        $datetime = DateTime::createFromFormat(
+            DateTimeInterface::RSS,
+            $dateStr,
+        );
+
+        // <dc:date> should be ISO 8601: https://web.resource.org/rss/1.0/modules/dc/
+        if ($datetime === false) {
+            $datetime = DateTime::createFromFormat(
+                DateTimeInterface::ISO8601,
+                $dateStr,
+            );
+        }
+
+        // We probably don't need this, but let's keep it just in case
+        if ($datetime === false) {
+            $datetime = DateTime::createFromFormat(
+                DateTimeInterface::RFC822,
+                $dateStr,
+            );
+        }
+
+        if ($datetime === false) {
+            $datetime = DateTime::createFromFormat(
+                DateTimeInterface::RFC7231,
+                $dateStr,
+            );
+        }
+
+        if ($datetime === false) {
+            try {
+                $datetime = new DateTime($dateStr);
+            } catch (Exception $ex) {
+                // NOTE: Nothing to do here, but be ultimately failed to parse
+                // the time
+                $datetime = false;
+            }
+        }
+
+        if ($datetime === false) {
+            return null;
+        }
+
+        return $datetime;
+    }
+
+    protected static function parseItem(Feed $feed, SimpleXMLElement $xml): FeedItem
+    {
+        $item = new FeedItem();
+        $item->feed = $feed;
+
+        foreach ($xml->children() as $elementName => $xmlItemElement) {
+            switch ($elementName) {
+                case 'title':
+                    $item->title = $xmlItemElement->__toString();
+                    break;
+                case 'link':
+                    $item->link = $xmlItemElement->__toString();
+                    break;
+                case 'description':
+                    $item->description = $xmlItemElement->__toString();
+                    break;
+            }
+        }
+
+        foreach ($xml->children('dc', true) as $elementName => $xmlItemElement) {
+            switch ($elementName) {
+                case 'date':
+                    $dateString = $xmlItemElement->__toString();
+                    $item->date = static::parseDateTime($dateString);
+                    break;
+                case 'creator':
+                    $item->creator = $xmlItemElement->__toString();
+                    break;
+            }
+        }
+
+        return $item;
+    }
+}

library/Feeds/Parser/RSSParser.php

@@ -11,7 +11,7 @@
 use DateTimeInterface;
 
 /**
- * RSSParser is used to parse RSS feeds
+ * RSSParser is used to parse RSS 2.0 feeds
  */
 class RSSParser
 {
@@ -24,7 +24,7 @@ public static function parse(string $raw): Feed
         $xmlElement = new SimpleXMLElement($raw);
 
         if ($xmlElement->getName() !== 'rss') {
-            throw new Exception('Invalid RSS-Feed');
+            throw new Exception('Invalid RSS2.0-Feed');
         }
 
         $xmlElement->rewind();