Loggers can be autoconfigured for service classes implementing \Psr\Log\LoggerAwareInterface

You can now autoconfigure any service class that implements \Psr\Log\LoggerAwareInterface to be setter-injected with a logger defined in the same module with a service name following the pattern: 'logger.channel.<MODULE_NAME>'.

This means you no longer need to explicitly define a logger in your service class constructor.

For example:

example.services.yml:

services:
  _defaults:
    # autoconfigure must be on
    autoconfigure: true

  my_module.my_service:
    class: Drupal\my_module\MyService

  # The ID after `logger.channel.` must the the same machine name as the module.
  logger.channel.my_module:
    parent: logger.channel_base
    arguments: ['my_module']

Before

Explicitly requiring a logger in the constructor.

use \Psr\Log\LoggerInterface;

class LoggerAwareExample {

  protected LoggerInterface $logger;

  public function __construct(LoggerInterface $logger) {
    $this->logger = $logger;
  }
}

After

Container autoconfiguration sets the $logger class property provided by the trait via

use \Psr\Log\LoggerAwareInterface;
use \Psr\Log\LoggerAwareTrait;

class LoggerAwareExample implements LoggerAwareInterface {

  use LoggerAwareTrait;

  public function myMethod(): {
    $this->logger->debug(...); // Use the logger as normal
  }

}

In the above example the 'logger.channel.my_module' service will automatically be set on a $logger property in theLoggerAwareExample instance via \Psr\Log\LoggerAwareTrait::setLogger.

To make use of this feature, services must:

• Implement \Psr\Log\LoggerAwareInterface
• Import the \Psr\Log\LoggerAwareTrait trait.
• Utilize autoconfiguration for services.
• Have an existing logger.channel.my_module logger service.