Add redirect tracking and analysis features

Database Schema:
- Added redirect_url VARCHAR(2048) to pages table
- Added redirect_count INT DEFAULT 0 to pages table
- Added index on redirect_count for faster queries

Configuration:
- Created Config class with typed constants (PHP 8.3+)
- MAX_REDIRECT_THRESHOLD = 3 (configurable warning threshold)
- MAX_CRAWL_DEPTH = 50
- CONCURRENCY = 10

Backend Changes:
- Crawler now tracks redirects using Guzzle's redirect tracking
- Extracts redirect history from response headers
- Records redirect count and final destination URL
- Guzzle configured with max 10 redirects and tracking enabled

API Endpoint:
- New endpoint: /api.php?action=redirects
- Analyzes redirect types (permanent 301/308 vs temporary 302/303/307)
- Identifies excessive redirects (> threshold)
- Returns statistics and detailed redirect information

Frontend Changes:
- Added "Redirects" tab with:
  * Statistics overview (Total, Permanent, Temporary, Excessive)
  * Detailed table showing all redirects
  * Visual warnings for excessive redirects (yellow background)
  * Color-coded redirect counts (red when > threshold)
  * Status code badges (green for permanent, blue for temporary)

All quality checks pass:
- PHPStan Level 8: 0 errors
- PHPCS PSR-12: 0 errors

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

config/docker/init.sql

@@ -31,11 +31,14 @@ CREATE TABLE IF NOT EXISTS pages (
     meta_description TEXT,
     status_code INT,
     content_type VARCHAR(100),
+    redirect_url VARCHAR(2048),
+    redirect_count INT DEFAULT 0,
     crawled_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     FOREIGN KEY (crawl_job_id) REFERENCES crawl_jobs(id) ON DELETE CASCADE,
     INDEX idx_crawl_job (crawl_job_id),
     INDEX idx_url (url(255)),
     INDEX idx_status_code (status_code),
+    INDEX idx_redirect_count (redirect_count),
     UNIQUE KEY unique_job_url (crawl_job_id, url(255))
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 

src/api.php

@@ -217,6 +217,47 @@ try {
             ]);
             break;
 
+        case 'redirects':
+            $jobId = $_GET['job_id'] ?? 0;
+            $stmt = $db->prepare(
+                "SELECT url, title, status_code, redirect_url, redirect_count FROM pages " .
+                "WHERE crawl_job_id = ? AND redirect_count > 0 " .
+                "ORDER BY redirect_count DESC, url"
+            );
+            $stmt->execute([$jobId]);
+            $redirects = $stmt->fetchAll();
+
+            // Count redirect types
+            $permanent = 0;
+            $temporary = 0;
+            $excessive = 0;
+            $maxThreshold = 3; // From Config::MAX_REDIRECT_THRESHOLD
+
+            foreach ($redirects as $redirect) {
+                $code = $redirect['status_code'];
+                if ($code == 301 || $code == 308) {
+                    $permanent++;
+                } elseif ($code == 302 || $code == 303 || $code == 307) {
+                    $temporary++;
+                }
+                if ($redirect['redirect_count'] > $maxThreshold) {
+                    $excessive++;
+                }
+            }
+
+            echo json_encode([
+                'success' => true,
+                'redirects' => $redirects,
+                'stats' => [
+                    'total' => count($redirects),
+                    'permanent' => $permanent,
+                    'temporary' => $temporary,
+                    'excessive' => $excessive,
+                    'threshold' => $maxThreshold
+                ]
+            ]);
+            break;
+
         case 'delete':
             $jobId = $_POST['job_id'] ?? 0;
             $stmt = $db->prepare("DELETE FROM crawl_jobs WHERE id = ?");

src/classes/Config.php

@@ -0,0 +1,29 @@
+<?php
+
+/**
+ * Web Crawler - Configuration Class
+ *
+ * @copyright Copyright (c) 2025 Martin Kiesewetter
+ * @author    Martin Kiesewetter <mki@kies-media.de>
+ * @link      https://kies-media.de
+ */
+
+namespace App;
+
+class Config
+{
+    /**
+     * Maximum number of redirects before warning
+     */
+    public const int MAX_REDIRECT_THRESHOLD = 3;
+
+    /**
+     * Maximum crawl depth
+     */
+    public const int MAX_CRAWL_DEPTH = 50;
+
+    /**
+     * Number of parallel requests
+     */
+    public const int CONCURRENCY = 10;
+}

src/classes/Crawler.php

@@ -33,6 +33,10 @@ class Crawler
         $this->client = new Client([
             'timeout' => 30,
             'verify' => false,
+            'allow_redirects' => [
+                'max' => 10,
+                'track_redirects' => true
+            ],
             'headers' => [
                 'User-Agent' => 'WebCrawler/1.0'
             ]
@@ -144,6 +148,17 @@ class Crawler
         $contentType = $response->getHeaderLine('Content-Type');
         $body = $response->getBody()->getContents();
 
+        // Track redirects
+        $redirectUrl = null;
+        $redirectCount = 0;
+        if ($response->hasHeader('X-Guzzle-Redirect-History')) {
+            $redirectHistory = $response->getHeader('X-Guzzle-Redirect-History');
+            $redirectCount = count($redirectHistory);
+            if ($redirectCount > 0) {
+                $redirectUrl = end($redirectHistory);
+            }
+        }
+
         // Save page
         $domCrawler = new DomCrawler($body, $url);
         $title = $domCrawler->filter('title')->count() > 0
@@ -155,13 +170,24 @@ class Crawler
             : '';
 
         $stmt = $this->db->prepare(
-            "INSERT INTO pages (crawl_job_id, url, title, meta_description, status_code, content_type) " .
+            "INSERT INTO pages (crawl_job_id, url, title, meta_description, status_code, " .
-            "VALUES (?, ?, ?, ?, ?, ?) " .
+            "content_type, redirect_url, redirect_count) " .
+            "VALUES (?, ?, ?, ?, ?, ?, ?, ?) " .
             "ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id), status_code = VALUES(status_code), " .
-            "meta_description = VALUES(meta_description)"
+            "meta_description = VALUES(meta_description), redirect_url = VALUES(redirect_url), " .
+            "redirect_count = VALUES(redirect_count)"
         );
 
-        $stmt->execute([$this->crawlJobId, $url, $title, $metaDescription, $statusCode, $contentType]);
+        $stmt->execute([
+            $this->crawlJobId,
+            $url,
+            $title,
+            $metaDescription,
+            $statusCode,
+            $contentType,
+            $redirectUrl,
+            $redirectCount
+        ]);
         $pageId = $this->db->lastInsertId();
 
         // If pageId is 0, fetch it manually

src/index.php

@@ -251,6 +251,7 @@
                     <button class="tab active" onclick="switchTab('pages')">Seiten</button>
                     <button class="tab" onclick="switchTab('links')">Links</button>
                     <button class="tab" onclick="switchTab('broken')">Broken Links</button>
+                    <button class="tab" onclick="switchTab('redirects')">Redirects</button>
                     <button class="tab" onclick="switchTab('seo')">SEO Analysis</button>
                 </div>
 
@@ -303,6 +304,25 @@
                     </table>
                 </div>
 
+                <div class="tab-content" id="redirects-tab">
+                    <h3>Redirect Statistics</h3>
+                    <div id="redirectStats" class="stats" style="margin-bottom: 20px;"></div>
+                    <table>
+                        <thead>
+                            <tr>
+                                <th>URL</th>
+                                <th>Redirect To</th>
+                                <th>Status Code</th>
+                                <th>Redirect Count</th>
+                                <th>Type</th>
+                            </tr>
+                        </thead>
+                        <tbody id="redirectsBody">
+                            <tr><td colspan="5" class="loading">Keine Redirects gefunden</td></tr>
+                        </tbody>
+                    </table>
+                </div>
+
                 <div class="tab-content" id="seo-tab">
                     <h3>SEO Issues</h3>
                     <div id="seoStats" style="margin-bottom: 20px;"></div>
@@ -549,6 +569,56 @@
                     }
                 }
 
+                // Load redirects
+                const redirectsResponse = await fetch(`/api.php?action=redirects&job_id=${currentJobId}`);
+                const redirectsData = await redirectsResponse.json();
+
+                if (redirectsData.success) {
+                    const stats = redirectsData.stats;
+
+                    // Redirect Stats
+                    document.getElementById('redirectStats').innerHTML = `
+                        <div class="stat-box">
+                            <div class="stat-label">Total Redirects</div>
+                            <div class="stat-value">${stats.total}</div>
+                        </div>
+                        <div class="stat-box">
+                            <div class="stat-label">Permanent (301/308)</div>
+                            <div class="stat-value">${stats.permanent}</div>
+                        </div>
+                        <div class="stat-box">
+                            <div class="stat-label">Temporary (302/303/307)</div>
+                            <div class="stat-value">${stats.temporary}</div>
+                        </div>
+                        <div class="stat-box">
+                            <div class="stat-label">Excessive (>${stats.threshold})</div>
+                            <div class="stat-value" style="color: ${stats.excessive > 0 ? '#e74c3c' : '#27ae60'}">${stats.excessive}</div>
+                            <div class="stat-sublabel">threshold: ${stats.threshold}</div>
+                        </div>
+                    `;
+
+                    // Redirect Table
+                    if (redirectsData.redirects.length > 0) {
+                        document.getElementById('redirectsBody').innerHTML = redirectsData.redirects.map(redirect => {
+                            const isExcessive = redirect.redirect_count > stats.threshold;
+                            const isPermRedirect = redirect.status_code == 301 || redirect.status_code == 308;
+                            const redirectType = isPermRedirect ? 'Permanent' : 'Temporary';
+
+                            return `
+                                <tr style="${isExcessive ? 'background-color: #fff3cd;' : ''}">
+                                    <td class="url-cell" title="${redirect.url}">${redirect.url}</td>
+                                    <td class="url-cell" title="${redirect.redirect_url || '-'}">${redirect.redirect_url || '-'}</td>
+                                    <td><span class="status ${isPermRedirect ? 'completed' : 'running'}">${redirect.status_code}</span></td>
+                                    <td><strong ${isExcessive ? 'style="color: #e74c3c;"' : ''}>${redirect.redirect_count}</strong></td>
+                                    <td>${redirectType}</td>
+                                </tr>
+                            `;
+                        }).join('');
+                    } else {
+                        document.getElementById('redirectsBody').innerHTML = '<tr><td colspan="5" class="loading">Keine Redirects gefunden</td></tr>';
+                    }
+                }
+
                 // Update jobs table
                 loadJobs();
             } catch (e) {