Debugging is an essential skill for any WordPress developer. It helps identify and fix issues efficiently, ensuring a smooth and error-free website. In this guide, we’ll explore easy-to-follow techniques and examples in PHP to streamline your WordPress debugging process.

The easiest way

<?php
function debug_function(){
    var_dump($variable);
}
add_action( 'init', 'debug_function' );

Enable Debugging in WordPress:

Before diving into specific debugging techniques, make sure WordPress debugging is enabled. Open your wp-config.php file and set the following constants:

if ( ! defined( 'WP_DEBUG' ) ) {
	define( 'WP_DEBUG', true );
	define( 'WP_DEBUG_DISPLAY', false );
	define( 'WP_DEBUG_LOG', true );
}

• WP_DEBUG: Enable debugging.
• WP_DEBUG_LOG: Save errors to a debug.log file.
• WP_DEBUG_DISPLAY: Disable error display on the site.

If we set these constants, the site will understand that all logs made with the error_log() function will be recorded in the debug.log file within the wp-content folder of our site.

Debugging Techniques

• Using error_log for Custom Messages:

function custom_debug_message($message) {
    error_log($message);
}

// Example Usage
custom_debug_message('This is a custom debug message.');

• Inspecting Variables with var_dump:

$example_variable = 'Hello, WordPress!';

// Use var_dump to inspect the variable
var_dump($example_variable);

• WordPress debug_backtrace Function

function my_debug_function() {
    $trace = debug_backtrace();
    error_log('Function called from ' . $trace[1]['file'] . ' at line ' . $trace[1]['line']);
}

// Example Usage
my_debug_function();