Enhancing PHP Error Handling: A Guide to Effective Troubleshooting

Dealing with PHP errors can be a frustrating experience for developers. The inability to obtain meaningful error codes often hinders the debugging process. Fortunately, we stumbled upon a fantastic resource from perishablepress.com that has revolutionized our approach to PHP error handling.

In this blog post, we will delve into the invaluable techniques outlined in the article, offering you an easy-to-follow guide for enhancing your PHP error handling capabilities.

Preventing Public Display of PHP Errors via htaccess

To ensure that PHP errors are not publicly displayed, you can leverage the power of htaccess. This configuration file allows you to modify server settings. By incorporating the following lines of code into your htaccess file, you can suppress PHP errors from being shown to users:

# suppress PHP errors
php_flag display_startup_errors off
php_flag display_errors off
php_flag html_errors off
php_value docref_root 0
php_value docref_ext 0

Controlling the Level of PHP Error Reporting

Tailoring the level of PHP error reporting to your specific needs is essential. The flexibility of htaccess empowers you to set the desired error reporting level. The general format for adjusting the error reporting level is as follows:

# general directive for setting PHP error level
php_value error_reporting integer

There are several commonly used values for "integer," including:

• Complete error reporting: To enable comprehensive PHP error logging (excluding run-time notices), set the error-reporting integer value to "8191."
• Zend error reporting: To record both fatal and non-fatal compile-time warnings generated by the Zend scripting engine, use an error-reporting integer value of "128."
• Basic error reporting: For capturing run-time notices, compile-time parse errors, as well as run-time errors and warnings, assign the error-reporting integer value of "8."
• Minimal error reporting: If you wish to log only fatal run-time errors, utilise an error-reporting integer value of "1."

Disabling Logging of Repeated Errors

Often, PHP error logs become inundated with numerous entries of virtually identical errors, differing only in timestamps. To prevent this redundancy, add the following lines to your project's root htaccess file:

# disable repeated error logging
php_flag ignore_repeated_errors on
php_flag ignore_repeated_source on

With these settings, repeated errors will not be logged, even if they originate from distinct sources or locations. If you only want to disable repeated errors from the same source or file, you can comment out or delete the last line. Conversely, if you wish to include all repeated errors in your log file, change both "on" values to "off."

Example Rules in a Production Environment

To illustrate the practical implementation of these techniques in a production environment, here is an example htaccess configuration:

# PHP error handling for production servers

# disable display of startup errors
php_flag display_startup_errors off

# disable display of all other errors
php_flag display_errors off

# disable HTML markup of errors
php_flag html_errors off

# enable logging of errors
php_flag log_errors on

# disable ignoring of repeat errors
php_flag ignore_repeated_errors off

# disable ignoring of unique source errors
php_flag ignore_repeated_source off

# enable logging of PHP memory leaks
php_flag report_memleaks on

# preserve most recent error via php_errormsg
php_flag track_errors on

# disable formatting of error reference links
php_value docref_root 0

# disable formatting of error reference links
php_value docref_ext 0

# specify the path to the PHP error log
php_value error_log /home/path/public_html/domain/PHP_errors.log

# specify recording of all PHP errors
php_value error_reporting -1

# disable max error string length
php_value log_errors_max_len 0

# protect error log by preventing public access
<Files PHP_errors.log>
 Order allow,deny
 Deny from all
 Satisfy All
</Files>