feat: create the RDF Feed class model, all rdf feeds are created from this class

It provides the appropriate namespace map, alternate property xpath selector expressions that are
used in parsing rdf feeds

Author: Harrison Ifeanyichukwu

src/Feeds/RDFFeed.php

@@ -0,0 +1,58 @@
+<?php
+declare(strict_types = 1);
+
+namespace Forensic\FeedParser\Feeds;
+
+use Forensic\FeedParser\Enums\FeedTypes;
+use Forensic\FeedParser\XPath;
+use Forensic\FeedParser\FeedItems\RDFFeedItem;
+
+
+class RSSFeed extends BaseFeed
+{
+    public function __construct(XPath $xpath, string $default_lang,
+        bool $remove_styles, bool $remove_scripts)
+    {
+        $namespaces = [
+            'def' => 'http://purl.org/rss/1.0/',
+            'rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
+            'dc' => 'http://purl.org/dc/elements/1.1/',
+            'sy' => 'http://purl.org/rss/1.0/modules/syndication',
+            'enc' => 'http://purl.oclc.org/net/rss_2.0/enc#',
+            'content' => 'http://purl.org/rss/1.0/modules/content/',
+            'taxo' => 'http://purl.org/rss/1.0/modules/taxonomy/'
+        ];
+
+        $property_selectors = [
+            'id' => 'def:channel/@rdf:about || def:channel/dc:identifier',
+            'title' => 'def:channel/def:title || def:channel/dc:title',
+            'link' => 'def:channel/def:link',
+            'description' => 'def:channel/def:description || def:channel/dc:description',
+            'image' => [
+                'src' => 'def:image/def:url || def:image/@rdf:about',
+                'link' => 'def:image/def:link || def:channel/def:link',
+                'title' => 'def:image/def:title || def:image/dc:title || def:channel/def:title ' .
+                    '|| def:channel/dc:title'
+            ],
+            'copyright' => 'def:channel/dc:rights',
+            'lastUpdated' => 'def:channel/dc:date',
+            'generator' => 'def:channel/dc:publisher || def:channel/dc:creator',
+            'language' => 'def:channel/dc:language',
+            'category' => 'def:channel/dc:coverage || ' .
+                'def:channel/dc:subject/taxo:topic/@rdf:value || dc:subject',
+        ];
+
+        $items_selector = 'def:item';
+
+        parent::__construct(
+            new FeedTypes(FeedTypes::RDF_FEED),
+            $default_lang,
+            $xpath,
+            $namespaces,
+            $property_selectors,
+            $items_selector,
+            $remove_styles,
+            $remove_scripts
+        );
+    }
+}