display feed icons on frontpage

actions/FeedIconAction.php

@@ -0,0 +1,129 @@
+<?php
+
+class FeedIconAction implements ActionInterface
+{
+    private CacheInterface $cache;
+    private BridgeFactory $bridgeFactory;
+
+    public function __construct()
+    {
+        $this->cache = RssBridge::getCache();
+        $this->bridgeFactory = new BridgeFactory();
+    }
+
+    public function execute(array $request): void
+    {
+        $bridgeClassName = $request['bridgeClassName'] ?? null;
+
+        if (!$bridgeClassName || !class_exists($bridgeClassName)) {
+            $this->sendNotFoundResponse();
+        }
+
+        $cacheKey = $this->buildCacheKey($bridgeClassName);
+
+        list(
+            'imageData' => $imageData,
+            'mimeType' => $mimeType
+        ) = $this->readCache($cacheKey);
+
+        if ($imageData && $mimeType) {
+            $this->sendImageResponse($mimeType, $imageData);
+        } elseif ('' === $imageData && '' === $mimeType) {
+            // empty values means that the image was broken and could not be loaded
+            $this->sendNotFoundResponse();
+        }
+
+        $bridge = $this->bridgeFactory->create($bridgeClassName);
+        $imageUrl = $bridge->getIcon();
+
+        $imageUrl = $this->cleanImageUrl($imageUrl);
+
+        if (!filter_var($imageUrl, FILTER_VALIDATE_URL)) {
+            //store empty values to prevent further attempts to load broken image
+            $this->writeCache($cacheKey, '', '');
+            $this->sendNotFoundResponse();
+        }
+
+        list(
+            'imageData' => $imageData,
+            'mimeType' => $mimeType
+        ) = $this->readImageData($imageUrl);
+
+        if (false === $imageData || false === $mimeType) {
+            //store empty values to prevent further attempts to load broken image
+            $this->writeCache($cacheKey, '', '');
+            $this->sendNotFoundResponse();
+        }
+
+        $this->writeCache($cacheKey, $mimeType, $imageData);
+        $this->sendImageResponse($mimeType, $imageData);
+    }
+
+    private function sendNotFoundResponse(): void
+    {
+        header('HTTP/1.1 404 Not Found');
+        exit;
+    }
+
+    private function sendImageResponse(string $mimeType, string $imageData): void
+    {
+        header('Content-Type: ' . $mimeType);
+        echo $imageData;
+        exit;
+    }
+
+    private function buildCacheKey(string $bridgeClassName): string
+    {
+        return md5($bridgeClassName . 'icon');
+    }
+
+    private function cleanImageUrl(string $imageUrl): string
+    {
+        //negative look behind: replace duplicate slashes in path, but not in protocol part of uri
+        $imageUrl = preg_replace('~(?<!:)//~', '/', $imageUrl);
+        return str_replace(["\r", "\n"], '', $imageUrl);
+    }
+
+    private function writeCache(string $cacheKey, string $mimeType, string $imageData): void
+    {
+        $this->cache->set($cacheKey, ['imageData' => $imageData, 'mimeType' => $mimeType]);
+    }
+
+    private function readCache(string $cacheKey): array
+    {
+        return (array)$this->cache->get($cacheKey);
+    }
+
+    private function readImageData(string $imageUrl): array
+    {
+        $context = stream_context_create([
+            'http' => [
+                'timeout' => 5,
+                'user_agent' => Configuration::getConfig('http', 'useragent'),
+            ],
+        ]);
+
+        $handle = @fopen($imageUrl, 'r', false, $context);
+
+        if ($handle === false) {
+            return ['imageData' => false, 'mimeType' => false];
+        }
+        $metaData = stream_get_meta_data($handle);
+        $headers = $metaData['wrapper_data'];
+
+        $contentType = false;
+
+        foreach ($headers as $header) {
+            if (stripos($header, 'Content-Type:') === 0) {
+                $contentType = trim(substr($header, 13)); // 13 is the length of "Content-Type:"
+                break;
+            }
+        }
+
+        $imageData = stream_get_contents($handle);
+
+        fclose($handle);
+
+        return ['imageData' => $imageData, 'mimeType' => $contentType];
+    }
+}

actions/FrontpageAction.php

@@ -23,11 +23,10 @@ public function execute(array $request)
 
         $body = '';
         foreach ($bridgeClassNames as $bridgeClassName) {
-            if ($bridgeFactory->isEnabled($bridgeClassName)) {
-                $body .= BridgeCard::displayBridgeCard($bridgeClassName, $formats);
-                $activeBridges++;
-            } elseif ($showInactive) {
-                $body .= BridgeCard::displayBridgeCard($bridgeClassName, $formats, false) . PHP_EOL;
+            $isEnabled = $bridgeFactory->isEnabled($bridgeClassName);
+            if ($isEnabled || $showInactive) {
+                $body .= BridgeCard::displayBridgeCard($bridgeClassName, $formats, $isEnabled) . PHP_EOL;
+                $activeBridges += (int)$isEnabled;
             }
         }
 

bridges/BlizzardNewsBridge.php

@@ -57,4 +57,11 @@ protected function getSourceUrl()
         }
         return 'https://news.blizzard.com/' . $locale;
     }
+
+    public function getIcon()
+    {
+        return <<<icon
+https://blznews.akamaized.net/images/favicon-cb34a003c6f2f637ee8f4f7b406f3b9b120b918c04cabec7f03a760e708977ea9689a1c638f4396def8dce7b202cd007eae91946cc3c4a578aa8b5694226cfc6.ico
+icon;
+    }
 }

bridges/NiusBridge.php

@@ -23,6 +23,11 @@ class NiusBridge extends XPathAbstract
     const XPATH_EXPRESSION_ITEM_CATEGORIES = './/div[@class="subtitle"]/text()';
     const SETTING_FIX_ENCODING = false;
 
+    public function getIcon()
+    {
+        return 'https://www.nius.de/favicon.ico';
+    }
+
     protected function formatItemTitle($value)
     {
         return strip_tags($value);

lib/BridgeCard.php

@@ -20,7 +20,7 @@ public static function displayBridgeCard($bridgeClassName, $formats, $isActive =
 
         $uri = $bridge->getURI();
         $name = $bridge->getName();
-        $icon = $bridge->getIcon();
+        $icon = self::hasBrokenIcon($bridgeClassName) ? '' : $_SERVER['PHP_SELF'] . '?action=FeedIcon&bridgeClassName=' . $bridgeClassName;
         $description = $bridge->getDescription();
         $parameters = $bridge->getParameters();
         if (Configuration::getConfig('proxy', 'url') && Configuration::getConfig('proxy', 'by_bridge')) {
@@ -47,7 +47,7 @@ class="bridge-card"
                     data-short-name="$shortName"
                 >
 
-                <h2><a href="{$uri}">{$name}</a></h2>
+                <h2><img src="{$icon}" onerror="this.style.display='none'" /><a href="{$uri}">{$name}</a></h2>
                 <p class="description">{$description}</p>
                 <input type="checkbox" class="showmore-box" id="showmore-{$bridgeClassName}" />
                 <label class="showmore" for="showmore-{$bridgeClassName}">Show more</label>
@@ -371,4 +371,14 @@ private static function getCheckboxInput($entry, $id, $name)
         . ' />'
         . PHP_EOL;
     }
+
+    private static function hasBrokenIcon(string $bridgeClassName): bool
+    {
+        $logger = RssBridge::getLogger();
+        $cacheFactory = new CacheFactory($logger);
+        $cache = $cacheFactory->create();
+        $cacheKey = md5($bridgeClassName . 'icon');
+        $cachedImage = (array)$cache->get($cacheKey);
+        return isset($cachedImage['imageData']) && '' === $cachedImage['imageData'] && isset($cachedImage['mimeType']) && '' === $cachedImage['mimeType'];
+    }
 }

lib/Debug.php

@@ -8,9 +8,10 @@ class Debug
     public static function isEnabled(): bool
     {
         $ip = $_SERVER['REMOTE_ADDR'] ?? 'x.y.z.1';
+        $isIconRequest = isset($_REQUEST['action']) && 'FeedIcon' === $_REQUEST['action'];
         $enableDebugMode = Configuration::getConfig('system', 'enable_debug_mode');
         $debugModeWhitelist = Configuration::getConfig('system', 'debug_mode_whitelist') ?: [];
-        if ($enableDebugMode && ($debugModeWhitelist === [] || in_array($ip, $debugModeWhitelist))) {
+        if ($enableDebugMode && !$isIconRequest && ($debugModeWhitelist === [] || in_array($ip, $debugModeWhitelist))) {
             return true;
         }
         return false;

static/style.css

@@ -182,6 +182,11 @@ section > h2 {
     font-weight: bold;
     text-align: center;
 }
+section > h2 img {
+    height: 1em;
+    margin-right: 10px;
+}
+
 section li {
     margin-left: 1em;
 }