Drupal 8 Logger Dependency Injection - Currently outdated - Update soon. Comment if interested and I'll speed up :)

my_module.module.php

<?php

/**
 * Log something.
 */
function log_something() {
  /Drupal::service('my_module.my_service')->logSomething('Word to the mutha');
}

my_module.services.yml

services:
  my_module.my_service:
    class: Drupal\my_module\Services\MyService
    arguments:
      - '@logger.factory'
      

MyService.php

<?php

namespace Drupal\my_module\Services;

use Drupal\Core\Logger\LoggerChannelFactory;

/**
 * Class MyService.
 *
 * @package Drupal\my_module\Services
 */
class MyService {

  /**
   * Logger Factory.
   *
   * @var \Drupal\Core\Logger\LoggerChannelFactory
   */
  protected $loggerFactory;

  /**
   * Constructor.
   */
  public function __construct(LoggerChannelFactory $loggerFactory) {
    $this->loggerFactory = $loggerFactory->get('my_module');
  }
  
  public function logSomething($something) {
    $this->loggerFactory->error('Yo: @something', [
      '@something' => $something,
    ]);
  }
  
}