Add general abstract classes for tests, starting with test classes for

RSS feeds

src/MD_STD.php

@@ -419,6 +419,44 @@ final class MD_STD {
 
     }
 
+    /**
+     * Check if a URL is reachable (200) using curl.
+     *
+     * @param string $url URL to validate.
+     *
+     * @return bool
+     */
+    public static function checkUrlIsReachable(string $url):bool {
+
+        if (filter_var($url, FILTER_VALIDATE_URL) === false) {
+            throw new MDInvalidUrl("URL to check (" . $url . ") does not seem to be a valid URL");
+        }
+
+        $ch = curl_init($url);
+        curl_setopt_array($ch, [
+            CURLOPT_AUTOREFERER    => true,
+            CURLOPT_CONNECTTIMEOUT => 5,
+            CURLOPT_ENCODING       => "",
+            CURLOPT_FOLLOWLOCATION => true,
+            CURLOPT_MAXREDIRS      => 1,
+            CURLOPT_NOBODY         => true,
+            CURLOPT_TIMEOUT        => 5,
+            // It's very important to let other webmasters know who's probing their servers.
+            CURLOPT_USERAGENT => 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:10.0.2) Gecko/20100101 Firefox/10.0.2',
+            CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_2_0,
+            CURLOPT_TCP_FASTOPEN => true,
+        ]);
+        curl_exec($ch);
+        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+        curl_close($ch);
+        if ($code !== 200) {
+            return false;
+        }
+
+        return true;
+
+    }
+
     /**
      * Sets and returns user language based on a session cookie.
      *

src/testing/MD_STD_RSS_TEST.php

@@ -0,0 +1,60 @@
+<?PHP
+/**
+ * Test for ensuring that search RSS feeds are generated correctly.
+ *
+ * @author Joshua Ramon Enslin <joshua@museum-digital.de>
+ */
+declare(strict_types = 1);
+
+use PHPUnit\Framework\TestCase;
+
+
+/**
+ * Tests for the manifest.
+ */
+abstract class MD_STD_RSS_TEST extends TestCase {
+
+    protected string $feed;
+
+    /**
+     * Protected function testRssFeedValidity.
+     *
+     * @return void
+     */
+    final public function testRssFeedValidity() {
+
+        $domDoc = new DomDocument();
+        self::assertTrue($domDoc->loadXML($this->feed));
+        self::assertTrue($domDoc->schemaValidate(__DIR__ . "/../../assets/xsd/Rss2.xsd"));
+        unset($domDoc);
+
+    }
+
+    /**
+     * Checks for the availability of RSS feed links and encosures.
+     *
+     * @return void
+     */
+    final public function testRssFeedLinksAndEnclosure() {
+
+        if (!($xmlData = simplexml_load_string($this->feed))) {
+            throw new Exception("Failed to load RSS feed string to SimpleXML element");
+        }
+
+        self::assertNotEmpty((string)$xmlData->channel->title);
+        self::assertTrue(MD_STD::checkUrlIsReachable((string)$xmlData->channel->image->url), "Path " . $xmlData->channel->image->url . " does not appear to be a reachable URL");
+        self::assertTrue(MD_STD::checkUrlIsReachable((string)$xmlData->channel->image->link), "Path " . $xmlData->channel->image->link . " does not appear to be a reachable URL");
+
+        self::assertTrue(MD_STD::checkUrlIsReachable((string)$xmlData->channel->item->link), "Path " . $xmlData->channel->item->link . " does not appear to be a reachable URL");
+
+        if (($firstEntryImg = $xmlData->channel->item->enclosure) === null) {
+            throw new Exception("First item does not seem to have an enclosure");
+        }
+        if (($firstEntryImgAttr = $firstEntryImg->attributes()) === null) {
+            throw new Exception("First enclosure does not seem to have attributes");
+        }
+
+        self::assertTrue(MD_STD::checkUrlIsReachable((string)$firstEntryImgAttr->url), "First enclosure does not appear to be a reachable URL (" . $firstEntryImgAttr->url . ")");
+
+    }
+}