Modernizing Logging For WordPress
As PHP moves forward, so must WordPress. This plugin helps WordPress use the tools of modern PHP. Monolog — PHP's most popular logging package — is a composer package. Since WordPress doesn't currently have a universal way to support composer, this WordPress plugin is meant to start bridging the gap. This logger is PSR-3 compliant, a PHP standard which Monolog also uses.
The current version is 0.2.0. This project uses semantic versioning.
- Upload the
wp-debug-loggerfolder to the/wp-content/plugins/directory - Activate the plugin through the 'Plugins' menu in WordPress
- Enable Debugging in your
wp-config.php
In order to enable standard debugging in WordPress, you'll need to add
some settings to your wp-config.php file.
define( 'WP_DEBUG', true );
define( 'WP_DEBUG_DISPLAY', false );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_MINIMUM_LEVEL', 'debug' );
// For good measure, this will hide errors from being displayed on-screen
@ini_set('display_errors', 0);WP_DEBUG_MINIMUM_LEVEL is a new constant that determines the minimum
severity level you wish to write to your wp-content/debug.log file. In
your development environment, I recommend using debug so you can see
all the errors being written. For your production environment, I'd
recommend the error level, so you can capture all the significant
problems. Here are the values to use: emergency, alert, critical,
error, warning, notice, info, debug. Note: they're all lowercase, as
the value is case-sensitive.
In your development environment, you may choose to set
WP_DEBUG_DISPLAY to true, so the error messages show in your
browser. However, I strongly recommend that you do not change it,
for your production environment. These settings can be placed
anywhere above the line.
/* That’s all, stop editing! Happy blogging. */
There are 8 logging levels available, defined by RFC 5424. The levels specified in order from the most severe to the least severe:
- Emergency: system is unusable
- Alert: action must be taken immediately
- Critical: critical conditions
- Error: error conditions
- Warning: warning conditions
- Notice: normal but significant condition
- Info: informational messages
- Debug: debug-level messages
The work of writing to the wp-content/debug.log file is done by the
Logger class. It determines the format of the message, and makes use of
the error_log() function PHP provides to do the writing. In this way,
this plugin acts like syntactic sugar in a more modern PHP way.
Each of the logging levels, has a corresponding method in the Logger class. Here's how to use the Logger class from your code.
$logger = new \WP_Debug_Logger\Logger();
$logger->error('The SQL query returned zero rows');it's recommended that you replace fully namespaced class names with an import at the top of your file.
use WP_Debug_Logger\Logger;
// ... your code ...
$logger = new Logger();
$logger->error('The SQL query returned zero rows');If you have a Laravel background, you may be used to using Laravel's Log
facade. While there is no service container to access, I did create a
Log class with static methods to wrap the Logger class. So you can
change the above example to read as follows.
use WP_Debug_Logger\Log;
// ... your code ...
Log::error('The SQL query returned zero rows');Here's the list of all static methods for the Log class
Log::emergency( 'This is an emergency message' );
Log::alert( 'This is an alert message' );
Log::critical( 'This is a critical message' );
Log::error( 'This is an error message' );
Log::warning( 'This is a warning message' );
Log::notice( 'This is a notice message' );
Log::info( 'This is a info message' );
Log::debug( 'This is a debug message' );Sometimes writing a simple message isn't enough. Wouldn't it be nice if you could include some data? Then you can make sure that the data has the content you think it does. If you're on your local environment, using the step debugging tools in XDebug will give you superior results. On a server though, it's useful to write the data to your log.
Please do not log passwords, secret keys, or other sensitive data.
Each of these methods, accepts an associative array as an optional second parameter. The keys of the array are used to identify replacement strings, and the value will be interpolated.
Log::debug(
'Success! The user "{username}" logged in!',
[ 'username' => 'awoods' ]
);Occasionally, you need to use print_r() on a piece of data, in order
to see how it's structured. To make it easy for you, the print()
method will write the print_r() data to the log as a debug level
message. It's good for examining the structure of a piece of data, but i
don't recommend leaving this in your code - since it makes your log less
scannable.
Log::print(
'your message here',
$your_data
);The var_dump() is related to print_r() in purpose, in that you can
see how data is structured. However, it also includes length
information. The dump() method will write the var_dump() data to the
log as a debug level message. Just like the print method, I don't
recommend leaving this in your code - since it makes your log less
scannable.
Log::dump(
'your message here',
$your_data
);One of the key features of the WordPress error model, is the WP_Error class. There are some functions that will return an WP_Error object, instead of false, like many PHP functions. Now you have an easy way to log these objects. Here's how you'd call it.
Log::wp_error(
$error_level,
$log_message,
$your_data
);The $error_level must be one of these values: emergency, alert, critical, error, warning, notice, info, debug. In the event you don't, an exception will be thrown.
if ( is_wp_error( $result ) ) {
Log::wp_error(
'critical',
'This very important query has a severe problem',
$result
);
}You still can. However, the plugin will add value to your logging efforts. Using this logger will add structure io the debug.log file, and give you a modern PHP interface to control the amount of logging in your website. Using a method with the logging level indicates the severity of the message.
- Features
- Language Translations
- Screenshots
- Submit Issues
- Project Creator: Andrew Woods