zend-expressive console cli commands

zend-expressive does not come out of the box with a console for handling cli commands. However with minimal effort you can add this and make full use of the container and its dependencies.

Install Symfony Console

First the Symfony console needs to be installed.

$ composer require symfony/console

Creating The Console

Next will be the console bootstrap file. It loads everything that’s needed and inject the commands from the configuration.

<?php // console.php

require __DIR__ . '/vendor/autoload.php';

use Symfony\Component\Console\Application;

/** @var \Interop\Container\ContainerInterface $container */
$container = require __DIR__ . '/config/container.php';
$application = new Application('Application console');

$commands = $container->get('config')['console']['commands'];
foreach ($commands as $command) {
    $application->add($container->get($command));
}

$application->run();

The console needs to know which commands to setup. Here the console -> commands key is chosen, however you can change this as you like.

<?php // config/autoload/console.global.php

return [
    'dependencies' => [
        'invokables' => [
        ],

        'factories' => [
        ],
    ],

    'console' => [
        'commands' => [
        ],
    ],
];

And that’s about it. You’ve got a working console.

Example greet command

But what is a console without a command. Let’s re-create the example greet command from the Symfony cookbook. First up is the command itself. To get a better idea of what you really can do, a logger is injected to log the executed command.

<?php // src/App/Command/GreetCommand.php

namespace App\Command;

use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Monolog\Logger;

class GreetCommand extends Command
{
    private $logger;

    /**
     * Constructor
     */
    public function __construct(Logger $logger)
    {
        $this->logger = $logger;

        parent::__construct();
    }

    /**
     * Configures the command
     */
    protected function configure()
    {
        $this
            ->setName('demo:greet')
            ->setDescription('Greet someone')
            ->addArgument(
                'name',
                InputArgument::OPTIONAL,
                'Who do you want to greet?'
            )
            ->addOption(
                'yell',
                null,
                InputOption::VALUE_NONE,
                'If set, the task will yell in uppercase letters'
            );
    }

    /**
     * Executes the current command
     */
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $name = $input->getArgument('name');
        if ($name) {
            $text = 'Hello ' . $name;
        } else {
            $text = 'Hello';
        }

        if ($input->getOption('yell')) {
            $text = strtoupper($text);
        }

        $output->writeln($text);

        $this->logger->info('GreetCommand triggered', ['name' => $name]);
    }
}

Most likely dependencies are needed, which are injected with a factory. In this example an instance of Monolog is injected.

<?php // src/App/Command/GreetCommandFactory.php

namespace App\Command;

use Interop\Container\ContainerInterface;
use Monolog\Logger;

class GreetCommandFactory
{
    public function __invoke(ContainerInterface $container)
    {
        return new GreetCommand(
            $container->get(Logger::class)
        );
    }
}

Add this command and its factory to the configuration so it can actually be used.

<?php // config/autoload/console.global.php

return [
    'dependencies' => [
        'invokables' => [
        ],

        'factories' => [
            App\Command\GreetCommand::class => App\Command\GreetCommandFactory::class,
        ],
    ],

    'console' => [
        'commands' => [
            App\Command\GreetCommand::class,
        ],
    ],
];

And now it’s ready to be used:

$ php console.php demo:greet world
$ php console.php demo:greet world --yell