Methods to configure PHP error and exception logging include: 1. Set the appropriate error reporting level, use E_ALL in the development environment, and block E_NOTICE and other non-critical errors in the production environment; 2. Use the error_log() function to manually record specific events or exceptions, which can be captured and written in try-catch; 3. Configure php.ini to enable automatic logging, set log_errors=On and error_log paths, or implement it through .htaccess and ini_set; 4. Use log libraries such as Monolog to improve flexibility, support logging to files, databases, external services, and provide structured logs and context information.

Logging errors and exceptions in PHP is essential for debugging and maintaining applications. Without proper logging, it's hard to know what went wrong when something breaks—especially in production environments where you don't want error messages displayed directly to users. Here's how to do it effectively.

Set the right error reporting level

PHP has several levels of errors (like E_NOTICE , E_WARNING , E_ERROR , etc.), and you can control which ones get reported using the error_reporting() function or your php.ini settings.

For development:

 error_reporting(E_ALL);

For production:

 error_reporting(E_ALL & ~E_NOTICE & ~E_DEPRECATED & ~E_STRICT);

This ensures that serious issues are caught during development, but minor warnings or notices don't clutter logs in production.

Also, make sure display_errors is off in production by setting it in php.ini :

 display_errors = Off

Use error_log() to write logs manually

If you want to log specific events or exceptions, PHP provides the built-in error_log() function. It lets you send an error message to a file, syslog, or even an email.

Example:

 error_log("An error occurred: $errorMessage", 3, "/var/log/myapp.log");

You can also integrate this inside try-catch blocks to log exceptions:

 try {
    // some code that might throw an exception
} catch (Exception $e) {
    error_log("Exception caught: " . $e->getMessage(), 3, "/var/log/myapp.log");
}

This is useful when you need fine-grained control over what gets logged and where.

Configure PHP to log errors automatically

Instead of manually writing every log entry, configure PHP to log all errors on its own. In your php.ini , set:

 log_errors = On
error_log = /var/log/php_errors.log

Make sure the web server has write access to the log file. This way, any uncaught error or warning will be written to the specified log file automatically.

If you're on shared hosting and can't edit php.ini , you can use .htaccess :

 php_value log_errors 1
php_value error_log /path/to/your/php_errors.log

Or use ini_set in a script (though it won't catch parse errors):

 ini_set('log_errors', 1);
ini_set('error_log', '/var/log/myapp_errors.log');

Consider using a logging library

While PHP's native tools work fine for small projects, larger applications benefit from structured logging libraries like Monolog . These offer more flexibility—like logging to files, databases, Slack, or external services like Sentry or Papertrail.

With Monolog, you can do something like:

 use Monolog\Logger;
use Monolog\Handler\StreamHandler;

// Create the logger
$logger = new Logger('name');
// Now add a handler to store logs in a file
$logger->pushHandler(new StreamHandler('/var/log/myapp.log', Logger::WARNING));

// Example usage
try {
    // some risky operation
} catch (\Exception $e) {
    $logger->warning($e->getMessage());
}

Libraries like these help organize your logs, add context, and support different output formats like JSON, which makes analysis easier later.

That's basically it. Whether you're building a simple script or a full app, setting up error logging properly helps you catch problems early and keep things running smoothly.

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