Getting services from the command class - php

Question

How can I get a service from the command class? I have been trying to use ContainerAwareCommand as the parent of my command class, and then just using $this->getContainer()->get('my_service'), but when I run the command in cli, I get the following error:
Call to undefined method Symfony\Component\Console\Application::getKernel()
inside the getContainer() method of the ContainerAwareCommand class.
The file through which I run the command is:
<?php
require_once __DIR__.'/../vendor/autoload.php';
require_once __DIR__.'/AppKernel.php';
use AppBundle\Console\Command\ChangeEmailCommand;
use Symfony\Component\Console\Application;
use Symfony\Component\Console\Input\ArgvInput;
use Symfony\Component\Debug\Debug;
$input = new ArgvInput();
$env = $input->getParameterOption(array('--env', '-e'), getenv('SYMFONY_ENV') ?: 'dev');
$debug = getenv('SYMFONY_DEBUG') !== '0' && !$input->hasParameterOption(array('--no-debug', '')) && $env !== 'prod';
if ($debug) {
Debug::enable();
}
$kernel = new AppKernel($env, $debug);
$application = new Application($kernel);
$application->add(new ChangeEmailCommand());
$application->run();

Answer 1

You have to use the Application of the FrameworkBundle instead of the Console component. This class extends the one in the Console component, but adds awareness of the Kernel and the Container. Your Application version doesn't have this awareness (as it's designed for standalone use, outside of the Symfony context), resulting in a "method getKernel() does not exists".
So change this:
use Symfony\Component\Console\Application;
To:
use Symfony\Bundle\FrameworkBundle\Console\Application;
Btw, normally you won't need to create this file yourself. You can just use app/console in the Standard Edition: https://github.com/symfony/symfony-standard/blob/2.7/app/console when you installed Symfony using the installer/composer create-project.