Centralize HTTP limits

link-meta.php

@@ -1,13 +1,16 @@
 <?php
 declare(strict_types=1);
+require_once __DIR__ . '/http-limits.php';
 
-function httpContext(int $timeout = 8) {
+function httpContext(?int $timeout = null) {
+    $limits = httpLimits();
+    $resolvedTimeout = $timeout === null ? $limits['timeout'] : max(1, $timeout);
     return stream_context_create([
         'http' => [
-            'timeout' => $timeout,
+            'timeout' => $resolvedTimeout,
             'follow_location' => 1,
-            'max_redirects' => 4,
-            'user_agent' => 'star-citizen.de-linkbot/1.0',
+            'max_redirects' => $limits['max_redirects'],
+            'user_agent' => $limits['user_agent'],
             'ignore_errors' => true
         ],
         'ssl' => [
@@ -66,10 +69,14 @@ function resolveUrl(string $url, string $baseUrl): ?string {
     return $baseParts['scheme'] . '://' . $baseParts['host'] . $path . $url;
 }
 
-function safeFetch(string $url, int $timeout = 8): ?string {
+function safeFetch(string $url, ?int $timeout = null): ?string {
+    $limits = httpLimits();
     $ctx = httpContext($timeout);
     $content = @file_get_contents($url, false, $ctx);
-    return $content === false ? null : $content;
+    if ($content === false || strlen($content) > $limits['max_bytes']) {
+        return null;
+    }
+    return $content;
 }
 
 function downloadImageFromUrl(string $url, string $baseUrl, string $destinationFolder = 'upl/'): ?string {
@@ -82,8 +89,8 @@ function downloadImageFromUrl(string $url, string $baseUrl, string $destinationF
         return null;
     }
 
-    $imageContent = safeFetch($resolved, 10);
-    if ($imageContent === null || strlen($imageContent) === 0 || strlen($imageContent) > (5 * 1024 * 1024)) {
+    $imageContent = safeFetch($resolved);
+    if ($imageContent === null || strlen($imageContent) === 0) {
         return null;
     }
 
@@ -130,7 +137,7 @@ function getPageInfo(string $url): array {
         return $ret;
     }
 
-    $html = safeFetch($normalized, 10);
+    $html = safeFetch($normalized);
     if ($html === null) {
         $ret['error'] = 'seite_nicht_erreichbar';
         return $ret;