Debugging is a crucial step when it comes to maintaining and improving a WordPress website as it allows you to identify and fix errors or issues in the site’s code, ensuring its optimal performance and functionality.
Whether it is a minor issue or a major problem affecting the entire website, debugging helps to fix these issues quickly, resulting in a better user experience.
By debugging your site, you can improve loading times, remove broken links, and resolve other technical issues that can affect visibility in search engine results.
How to debug a WordPress website
Let’s see how to do a simple debugging:
Enable WP_DEBUG
The first step is to enable WP_DEBUG, a debugging tool built into WordPress:
- Access site files through an FTP client or file manager.
- Locate the wp-config.php file, which is usually located inside the public folder.
- Open the wp-config.php file in a text editor.
- Find the line that says define(‘WP_DEBUG’, false); and change false to true.
- Save the changes and upload the modified wp-config.php file back to the server.
Enabling WP_DEBUG allows WordPress to display useful information about errors, notices, and warnings on the website frontend.
While WP_DEBUG is informative, it can clutter your website’s interface with debugging information. To address this, WordPress provides two additional tools: WP_DEBUG_LOG and WP_DEBUG_DISPLAY.
WP_DEBUG_LOG
WP_DEBUG_LOG allows you to save debugging information to a log file instead of displaying it in the website frontend.
Here’s how to enable it:
- Open the wp-config.php file on your WordPress site.
- Locate the line that says define(‘WP_DEBUG_LOG’, false); and change false to true.
- Save changes and upload the modified wp-config.php file.
Now, any debugging information will be logged to a file called debug.log. You can find this file in the wp-content directory of your WordPress installation.
WP_DEBUG_DISPLAY
WP_DEBUG_DISPLAY controls whether debug information is displayed in the website frontend.
By default, WP_DEBUG_DISPLAY is set to true, meaning that debug information will be displayed, however, in some cases, you may want to prevent it from appearing. To do this, follow these steps:
- Open the wp-config.php file on your WordPress site.
- Locate the line that says define(‘WP_DEBUG_DISPLAY’, true); and change it from true to false.
- Save changes and upload the modified wp-config.php file.
This will prevent debugging information from being displayed on your website while still allowing access to log file information.
Using script debugging
Script debugging is a technique for identifying and resolving issues related to scripts and stylesheets in WordPress.
By enabling SCRIPT_DEBUG, you gain access to valuable information for debugging these issues.
- Open the wp-config.php file on your WordPress site.
- Find the line that says define(‘SCRIPT_DEBUG’, false); and change false to true.
- Save changes and upload the modified wp-config.php file.
Once enabled, SCRIPT_DEBUG will load non-minified versions of scripts and stylesheets, making them easier to understand and debug.
Additional tools
In addition to WordPress’ built-in debugging tools, several plugins and tools can further enhance debugging capabilities.
Query Monitor
Query Monitor is a powerful debugging tool that provides detailed information about database queries, links, PHP errors, HTTP requests, and much more.
Allows you to monitor and analyze the performance of your WordPress website. The plugin adds a toolbar to the admin bar, providing easy access to vital debugging information.
Debug bar
Debug Bar is another useful debugging plugin that adds a debug menu to your WordPress admin bar, displaying a wealth of information about queries, cache, hooks, and more, making it easier to identify and troubleshoot issues.
Register obsolete notices
The Deprecation Alerts plugin is useful for identifying and deprecating outdated features or functions on your WordPress site as it helps you stay up to date with the latest practices by alerting you about any outdated code used on the site.
Browser Development Tools
Browser developer tools can prove invaluable when it comes to debugging WordPress sites by providing insight into your site’s behavior, allowing you to monitor network requests, inspect HTML and CSS, view console logs, and more.
Below are some commonly used browser development tools:
- Console – The console displays error messages, log output, and other debugging information. You can use it to inspect JavaScript errors or to log custom debug messages.
- Network – The Network dashboard shows all network requests made by your website, including their status, size, time, and the data they send or receive. It helps you identify performance bottlenecks and potential issues with external resources.
- Elements – The Elements panel allows you to inspect and modify your site’s HTML and CSS properties. You can use it to troubleshoot layout issues or experiment with styles in real time.
By using browser developer tools, you can identify issues related to front-end functionality, adjust CSS styles, and debug JavaScript code.
While debugging is essential to maintaining a healthy WordPress site, it’s crucial to prioritize security. Debugging can potentially expose sensitive information, such as database credentials or file paths, if not handled properly.
Here are some tips to ensure safety while debugging:
- Disable debugging features when they are no longer needed – Once you’ve resolved the issues on your website, remember to disable WP_DEBUG, WP_DEBUG_LOG, and any other debugging tools you’ve enabled. Leaving them active unnecessarily can expose your site to potential security risks.
- Avoid displaying debug information publicly – Make sure that debug information is not displayed in publicly accessible areas of your website. This includes disabling WP_DEBUG_DISPLAY and protecting access to log files.
- Restrict access to log files – Ensure that unauthorized people cannot access log files. This may involve securing file permissions or placing them outside of publicly accessible directories.
- Don’t include sensitive information in your debug code – Avoid including sensitive information, such as passwords or API keys, in your debug code. Any hardcoded credentials used for testing purposes should be removed or obfuscated before deploying your website to a live environment.
Following these precautions will help protect your website and ensure that debugging remains a useful and safe process.
Conclusions
Debugging is an essential aspect of maintaining a healthy WordPress website. By enabling WP_DEBUG, using additional debugging tools and techniques, and following security best practices, you can effectively identify and resolve issues on your WordPress site.
Approach debugging in a systematic way, using the tools and resources available to you and keeping security in mind. Doing so can keep your WordPress site running smoothly and ensure a positive user experience for your visitors.
Debugging helps you optimize your website’s performance, ensure its security, and improve its search engine rankings.