Console Commands

Console Commands

The Symfony framework provide lots of commands through the bin/console script (e.g. the well-known bin/console cache:clear command). These commands are created with the Console component. You can also use it to create your own commands.

Creating a Command

Commands are defined in classes which must be created in the Command namespace of your bundle (e.g. AppBundle\Command) and their names must end with the Command suffix.

For example, a command called CreateUser must follow this structure:

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// src/AppBundle/Command/CreateUserCommand.php
namespace AppBundle\Command;

use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

class CreateUserCommand extends Command
{
    protected function configure()
    {
        // ...
    }

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        // ...
    }
}

Configuring the Command

First of all, you must configure the name of the command in the configure() method. Then you can optionally define a help message and the input options and arguments:

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// ...
protected function configure()
{
    $this
        // the name of the command (the part after "bin/console")
        ->setName('app:create-users')

        // the short description shown while running "php bin/console list"
        ->setDescription('Creates new users.')

        // the full command description shown when running the command with
        // the "--help" option
        ->setHelp("This command allows you to create users...")
    ;
}

Executing the Command

After configuring the command, you can execute it in the terminal:

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$ php bin/console app:create-users

As you might expect, this command will do nothing as you didn't write any logic yet. Add your own logic inside the execute() method, which has access to the input stream (e.g. options and arguments) and the output stream (to write messages to the console):

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// ...
protected function execute(InputInterface $input, OutputInterface $output)
{
    // outputs multiple lines to the console (adding "\n" at the end of each line)
    $output->writeln([
        'User Creator',
        '============',
        '',
    ]);

    // outputs a message followed by a "\n"
    $output->writeln('Whoa!');

    // outputs a message without adding a "\n" at the end of the line
    $output->write('You are about to ');
    $output->write('create a user.');
}

Now, try executing the command:

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$ php bin/console app:create-user
User Creator
============

Whoa!
You are about to create a user.

Console Input

Use input options or arguments to pass information to the command:

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use Symfony\Component\Console\Input\InputArgument;

// ...
protected function configure()
{
    $this
        // configure an argument
        ->addArgument('username', InputArgument::REQUIRED, 'The username of the user.')
        // ...
    ;
}

// ...
public function execute(InputInterface $input, OutputInterface $output)
{
    $output->writeln([
        'User Creator',
        '============',
        '',
    ]);

    // retrieve the argument value using getArgument()
    $output->writeln('Username: '.$input->getArgument('username'));
}

Now, you can pass the username to the command:

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$ php bin/console app:create-user Wouter
User Creator
============

Username: Wouter
Read Console Input (Arguments & Options) for more information about console options and arguments.

Getting Services from the Service Container

To actually create a new user, the command has to access to some services. This can be done by making the command extend the ContainerAwareCommand instead:

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// ...
use Symfony\Bundle\FrameworkBundle\Command\ContainerAwareCommand;

class CreateUserCommand extends ContainerAwareCommand
{
    // ...

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        // ...

        // access the container using getContainer()
        $userManager = $this->getContainer()->get('app.user_manager');
        $userManager->create($input->getArgument('username'));

        $output->writeln('User successfully generated!');
    }
}

Now, once you created the required services and logic, the command will execute the generate() method of the app.user_manager service and the user will be created.

Command Lifecycle

Commands have three lifecycle methods that are invoked when running the command:

initialize() (optional)
This method is executed before the interact() and the execute() methods. Its main purpose is to initialize variables used in the rest of the command methods.
interact() (optional)
This method is executed after initialize() and before execute(). Its purpose is to check if some of the options/arguments are missing and interactively ask the user for those values. This is the last place where you can ask for missing options/arguments. After this command, missing options/arguments will result in an error.
execute() (required)
This method is executed after interact() and initialize(). It contains the logic you want the command to execute.

Testing Commands

Symfony provides several tools to help you test your commands. The most useful one is the CommandTester class. It uses special input and output classes to ease testing without a real console:

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// tests/AppBundle/Command/CreateUserCommandTest.php
namespace Tests\AppBundle\Command;

use AppBundle\Command\CreateUserCommand;
use Symfony\Component\Console\Application;
// use this if you're in the Symfony Framework
//use Symfony\Bundle\FrameworkBundle\Console\Application;
use Symfony\Component\Console\Tester\CommandTester;

class CreateUserCommandTest extends \PHPUnit_Framework_TestCase
{
    public function testExecute()
    {
        $application = new Application();

        // if you're in the Symfony framework, do this instead
        // extend the KernelTestCase class
        // self::bootKernel();
        // $application = new Application(self::$kernel);

        $application->add(new CreateUserCommand());

        $command = $application->find('app:create-user');
        $commandTester = new CommandTester($command);
        $commandTester->execute(array(
            'command'  => $command->getName(),

            // pass arguments to the helper
            'username' => 'Wouter',

            // prefix the key with a double slash when passing options,
            // e.g: '--some-option' => 'option_value',
        ));

        // the output of the command in the console
        $output = $commandTester->getDisplay();
        $this->assertContains('Username: Wouter', $output);

        // ...
    }
}

Tip

You can also test a whole console application by using ApplicationTester.

To be able to use the fully set up service container for your console tests you can extend your test from KernelTestCase:

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// ...
use Symfony\Component\Console\Tester\CommandTester;
use Symfony\Bundle\FrameworkBundle\Console\Application;
use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;

class CreateUserCommandTest extends KernelTestCase
{
    public function testExecute()
    {
        $kernel = $this->createKernel();
        $kernel->boot();

        $application = new Application($kernel);
        $application->add(new CreateUserCommand());

        $command = $application->find('app:create-user');
        $commandTester = new CommandTester($command);
        $commandTester->execute(array(
            'command'  => $command->getName(),
            'username' => 'Wouter',
        ));

        $output = $commandTester->getDisplay();
        $this->assertContains('Username: Wouter', $output);

        // ...
    }
}

Learn More

The console component also contains a set of "helpers" - different small tools capable of helping you with different tasks:

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.