Debugging with WP_DEBUG in Wordpress - Mini Project: Build & Apply

Debugging with WP_DEBUG in WordPress

📖 Scenario: You are building a WordPress site and want to find and fix errors easily. WordPress has a special tool called WP_DEBUG that helps show problems in your code.This project will guide you step-by-step to enable and use WP_DEBUG to see error messages and warnings on your site.

🎯 Goal: Enable WordPress debugging by setting WP_DEBUG to true in the wp-config.php file, configure error logging, and display errors on the site for easier troubleshooting.

📋 What You'll Learn

Edit the wp-config.php file

Create a variable to enable debugging

Configure error logging to a file

Enable error display on the site

💡 Why This Matters

🌍 Real World

Developers use WP_DEBUG to find mistakes in their WordPress themes and plugins quickly by seeing error messages.

💼 Career

Knowing how to enable and use WP_DEBUG is essential for WordPress developers and site maintainers to troubleshoot and fix issues efficiently.

1

Enable WP_DEBUG in wp-config.php

Open the wp-config.php file and add the line define('WP_DEBUG', true); before the line that says /* That's all, stop editing! Happy blogging. */ to turn on debugging.

Wordpress

<?php
// Some initial WordPress config code

define('WP_DEBUG', true);
/* That's all, stop editing! Happy blogging. */
# Your code here

Need a hint?

Use define('WP_DEBUG', true); exactly to enable debugging.

2

Enable error logging to a file

Add the line define('WP_DEBUG_LOG', true); below define('WP_DEBUG', true); in wp-config.php to save errors to a debug log file.

Wordpress

<?php
// Some initial WordPress config code

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
/* That's all, stop editing! Happy blogging. */
# Your code here

Need a hint?

Use define('WP_DEBUG_LOG', true); to log errors to wp-content/debug.log.

3

Enable error display on the site

Add the line define('WP_DEBUG_DISPLAY', true); below define('WP_DEBUG_LOG', true); in wp-config.php to show errors directly on your website pages.

Wordpress

<?php
// Some initial WordPress config code

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', true);
/* That's all, stop editing! Happy blogging. */
# Your code here

Need a hint?

Use define('WP_DEBUG_DISPLAY', true); to see errors on the site pages.

4

Complete wp-config.php with debugging setup

Ensure the wp-config.php file contains these three lines exactly before the stop editing comment:
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', true);

Wordpress

<?php
// Some initial WordPress config code

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', true);
/* That's all, stop editing! Happy blogging. */
# Your code here

Need a hint?

Check all three define lines are present exactly before the stop editing comment.