WordPress Debug Log Viewer Plugin

If you’d rather not have to open FTP or SSH to view your error logs and start debugging the free Foxco WordPress Debug Log Viewer might be of use for you.

Main Functionality:

• View WordPress debug.log directly from the admin panel (Tools > Debug Log)
• Real-time log monitoring with auto-refresh option
• Syntax highlighting for errors (red), warnings (yellow), and notices (blue/green)
• Dark theme log display for easy reading

Controls:

• Refresh – Manually reload the log
• Auto-Refresh – Toggle automatic refresh every 5 seconds
• Download – Download the current log file
• Clear Log – Empty the debug log file

Filters:

• Toggle visibility of errors, warnings, and notices
• Search/filter log entries in real-time
• Adjustable line limit (50-10000 lines)

Info Display:

• Shows if debug.log exists
• File size
• WP_DEBUG status
• WP_DEBUG_LOG status
• Helpful notice if debugging isn’t enabled

The plugin uses a clean, modern interface with responsive design and includes helpful syntax highlighting to make debugging easier.

Like everything Foxco does this plugin is dead-simple, clean and fast.. only 232 lines of code.

Click here to download the installable zip file.

<?php
/**
 * Plugin Name: Foxco Debug Log Viewer
 * Plugin URI: https://foxco.net
 * Description: Simple debug.log viewer for WordPress with real-time monitoring and log management
 * Version: 1.0.0
 * Author: Foxco
 * Author URI: https://foxco.net
 * License: GPL v2 or later
 * Text Domain: foxco-debug-viewer
 */

// Prevent direct access
if (!defined('ABSPATH')) {
    exit;
}

class Foxco_Debug_Log_Viewer {
    
    private $log_file;
    
    public function __construct() {
        $this->log_file = WP_CONTENT_DIR . '/debug.log';
        
        // Add admin menu
        add_action('admin_menu', array($this, 'add_admin_menu'));
        
        // AJAX handlers
        add_action('wp_ajax_foxco_get_log', array($this, 'ajax_get_log'));
        add_action('wp_ajax_foxco_clear_log', array($this, 'ajax_clear_log'));
        add_action('wp_ajax_foxco_download_log', array($this, 'ajax_download_log'));
        
        // Admin scripts
        add_action('admin_enqueue_scripts', array($this, 'enqueue_scripts'));
    }
    
    public function add_admin_menu() {
        add_management_page(
            'Debug Log Viewer',
            'Debug Log',
            'manage_options',
            'foxco-debug-log',
            array($this, 'render_admin_page')
        );
    }
    
    public function enqueue_scripts($hook) {
        if ($hook !== 'tools_page_foxco-debug-log') {
            return;
        }
        
        wp_enqueue_style(
            'foxco-debug-viewer',
            plugin_dir_url(__FILE__) . 'assets/style.css',
            array(),
            '1.0.0'
        );
        
        wp_enqueue_script(
            'foxco-debug-viewer',
            plugin_dir_url(__FILE__) . 'assets/script.js',
            array('jquery'),
            '1.0.0',
            true
        );
        
        wp_localize_script('foxco-debug-viewer', 'foxcoDebugViewer', array(
            'ajax_url' => admin_url('admin-ajax.php'),
            'nonce' => wp_create_nonce('foxco_debug_viewer')
        ));
    }
    
    public function render_admin_page() {
        if (!current_user_can('manage_options')) {
            wp_die(__('You do not have sufficient permissions to access this page.'));
        }
        
        $log_exists = file_exists($this->log_file);
        $log_size = $log_exists ? size_format(filesize($this->log_file), 2) : '0 B';
        $wp_debug_enabled = defined('WP_DEBUG') && WP_DEBUG;
        $wp_debug_log_enabled = defined('WP_DEBUG_LOG') && WP_DEBUG_LOG;
        
        ?>
        <div class="wrap foxco-debug-viewer">
            <h1>
                <span class="dashicons dashicons-admin-tools"></span>
                Foxco Debug Log Viewer
            </h1>
            
            <div class="foxco-debug-header">
                <div class="foxco-debug-info">
                    <div class="info-item">
                        <strong>Log File:</strong> 
                        <?php echo $log_exists ? '<span class="status-active">Active</span>' : '<span class="status-inactive">Not Found</span>'; ?>
                    </div>
                    <div class="info-item">
                        <strong>File Size:</strong> <?php echo esc_html($log_size); ?>
                    </div>
                    <div class="info-item">
                        <strong>WP_DEBUG:</strong> 
                        <?php echo $wp_debug_enabled ? '<span class="status-active">Enabled</span>' : '<span class="status-inactive">Disabled</span>'; ?>
                    </div>
                    <div class="info-item">
                        <strong>WP_DEBUG_LOG:</strong> 
                        <?php echo $wp_debug_log_enabled ? '<span class="status-active">Enabled</span>' : '<span class="status-inactive">Disabled</span>'; ?>
                    </div>
                </div>
                
                <div class="foxco-debug-actions">
                    <button id="foxco-refresh-log" class="button button-primary">
                        <span class="dashicons dashicons-update"></span> Refresh
                    </button>
                    <button id="foxco-auto-refresh" class="button" data-active="0">
                        <span class="dashicons dashicons-backup"></span> Auto-Refresh: OFF
                    </button>
                    <button id="foxco-download-log" class="button">
                        <span class="dashicons dashicons-download"></span> Download
                    </button>
                    <button id="foxco-clear-log" class="button button-secondary">
                        <span class="dashicons dashicons-trash"></span> Clear Log
                    </button>
                </div>
            </div>
            
            <?php if (!$wp_debug_enabled || !$wp_debug_log_enabled): ?>
            <div class="notice notice-warning">
                <p>
                    <strong>Debug logging is not fully enabled.</strong> 
                    To enable debug logging, add these lines to your wp-config.php file:
                </p>
                <pre>define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);</pre>
            </div>
            <?php endif; ?>
            
            <div class="foxco-debug-controls">
                <label>
                    <input type="checkbox" id="foxco-filter-errors" checked> 
                    Show Errors
                </label>
                <label>
                    <input type="checkbox" id="foxco-filter-warnings" checked> 
                    Show Warnings
                </label>
                <label>
                    <input type="checkbox" id="foxco-filter-notices" checked> 
                    Show Notices
                </label>
                <label>
                    <input type="number" id="foxco-line-limit" min="50" max="10000" step="50" value="500">
                    Lines to Display
                </label>
                <input type="text" id="foxco-search" placeholder="Search log..." />
            </div>
            
            <div id="foxco-log-container" class="foxco-log-container">
                <div class="foxco-loading">Loading debug log...</div>
            </div>
        </div>
        <?php
    }
    
    public function ajax_get_log() {
        check_ajax_referer('foxco_debug_viewer', 'nonce');
        
        if (!current_user_can('manage_options')) {
            wp_send_json_error('Insufficient permissions');
        }
        
        $lines = isset($_POST['lines']) ? intval($_POST['lines']) : 500;
        
        if (!file_exists($this->log_file)) {
            wp_send_json_success(array(
                'content' => 'No debug log found. Debug logging may not be enabled.',
                'size' => 0,
                'modified' => ''
            ));
        }
        
        $content = $this->get_log_tail($lines);
        
        wp_send_json_success(array(
            'content' => $content,
            'size' => size_format(filesize($this->log_file), 2),
            'modified' => date('Y-m-d H:i:s', filemtime($this->log_file))
        ));
    }
    
    public function ajax_clear_log() {
        check_ajax_referer('foxco_debug_viewer', 'nonce');
        
        if (!current_user_can('manage_options')) {
            wp_send_json_error('Insufficient permissions');
        }
        
        if (file_exists($this->log_file)) {
            file_put_contents($this->log_file, '');
            wp_send_json_success('Log file cleared successfully');
        } else {
            wp_send_json_error('Log file not found');
        }
    }
    
    private function get_log_tail($lines = 500) {
        if (!file_exists($this->log_file)) {
            return '';
        }
        
        $file = new SplFileObject($this->log_file, 'r');
        $file->seek(PHP_INT_MAX);
        $total_lines = $file->key() + 1;
        
        $start_line = max(0, $total_lines - $lines);
        
        $content = array();
        $file->seek($start_line);
        
        while (!$file->eof()) {
            $line = $file->current();
            if ($line !== false) {
                $content[] = $line;
            }
            $file->next();
        }
        
        return implode('', $content);
    }
}

// Initialize plugin
new Foxco_Debug_Log_Viewer();