How to build Console Applications @ phplx

In some cases you feel the need to have some specific command-line commands for deployment, testing some code or do any other specific task.

The Symfony2 Console component is a tool that gives you in a simple and easy way to build a console application with your own command-line commands.

This talk is an introduction to the Console component and a walkthrough on how to use it in an effective way.

Transcript

1. Daniel Gomes
   @danielcsgomes
   October 17, 2013
   icon by Austin Andrews © http://thenounproject.com/Templarian
   How to Build
   Console Applications
   

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2. • Software Engineer @ GuestCentric Systems
   • ZCE PHP 5.3, OCP MySQL 5 Developer, CSM
   • @danielcsgomes
   about me
   

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3. Lots of scripts
   Too many di!erent tools
   Tedious and boring
   

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4. Centralize your tools
   Have interactive tools
   Easy to use by everyone
   Usage manual
   what about
   

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5. Meet
   symfony
   Console Component
   

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6. • Application
   • Command
   • Input
   • Output
   • Helpers
   • Events
   • Formatters
   console component toolset
   

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7. APPLICATION
   COMMAND A
   COMMAND B
   COMMAND C
   plug-in & run
   

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8. {
   "require": {
   "symfony/console": "2.3.*@dev"
   }
   }
   install via composer
   zero dependencies
   

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9. // app.php
   require_once __DIR__ . '/vendor/autoload.php';
   use Symfony\Component\Console\Application;
   $app = new Application('Clear Cache App', '0.0.1');
   $app->run();
   Bootstrapping the application
   

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10. $ php app.php
    

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11. basic command
    

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12. // Command/CacheClearCommand.php
    namespace DCSG\Command;
    use Symfony\Component\Console\Command\Command;
    class CacheClearCommand extends Command
    {
    protected function configure()
    {
    $this
    ->setName('cache:clear')
    ->setDescription('Clears Application Cache')
    ->setHelp(<<The cache:clear command removes all files inside
    the cache directory.
    EOF
    );
    }
    // ...
    }
    

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13. require_once __DIR__ . '/vendor/autoload.php';
    use DCSG\Command\CacheClearCommand;
    use Symfony\Component\Console\Application;
    $app = new Application('Clear Cache App', '0.0.1');
    $app->add(new CacheClearCommand());
    $app->run();
    adding to application
    

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14. $ php app.php
    

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15. $ php app.php help cache:clear
    

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16. add arguments
    

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17. • ordered
    • input type:
    • optional
    • required
    • array
    arguments are:
    

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18. // Command/CacheClearCommand.php
    $this->addArgument(
    'directory', // name
    InputArgument::OPTIONAL, // input type
    'The cache directory', // description
    './cache' // default value
    );
    adding an argument
    

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19. add options
    

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20. • unordered
    • input type:
    • optional
    • required
    • array
    • none (no input)
    options are:
    

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21. // CacheClearCommand.php
    $this->addOption(
    'force', // name
    'f', // shortname
    InputOption::VALUE_NONE, // input type
    'Forces to clear the cache.' // description
    );
    adding an option
    

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22. add logic
    

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23. // Command/CacheClearCommand.php
    protected function execute(
    InputInterface $input,
    OutputInterface $output)
    {
    // Logic here
    }
    execute the command
    

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24. // Command/CacheClearCommand.php
    protected function execute(InputInterface $input, OutputInterface $output)
    {
    // Reads the Input
    $directory = $input->getArgument('directory');
    // Removes all files inside the directory
    $counter = 0;
    $files = glob($cacheDir . '/*');
    foreach ($files as $file) {
    if (is_file($file)) {
    unlink($file);
    $counter++;
    }
    }
    // Writes the Output
    $output->writeln(sprintf('Cache cleared. Removed %d files.', $counter));
    }
    

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25. always
    validate the input
    

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26. // Command/CacheClearCommand.php
    // Reads the Input
    $directory = $input->getArgument('directory');
    // Validate the argument input
    if (false === $cacheDir = realpath($directory)) {
    throw new \InvalidArgumentException('Directory does't
    exist.');
    }
    // InputOption::VALUE_NONE does not need to be validate
    // since it does not accept parameters
    // in this case will return true or false
    $force = $input->getOption('force');
    

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27. $ php app.php cache:clear /foo/bar
    

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28. interact
    with the user
    

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29. • Dialog helper
    • Formatter helper
    • Progress helper
    • Table helper
    

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30. dialog HELPER
    

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31. // Symfony/Component/Console/Helper/DialogHelper.php
    public function select(...){...}
    public function ask(...){...}
    public function askConfirmation(...){...}
    public function askHiddenResponse(...){...}
    public function askAndValidate(...){...}
    public function askHiddenResponseAndValidate (...){...}
    

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32. // Command/CacheClearCommand.php
    // ...
    // Ask the user if it's the right directory
    $dialog = $this->getHelperSet()->get('dialog');
    $answer = $dialog->askConfirmation(
    $output,
    sprintf('Remove all files in: %s ? (no)', $cacheDir),
    false // default value
    );
    // ...
    Remove all files in: ./cache ? (no) yes
    OUTPUT
    

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33. OUTPUT
    // examples/Helpers/select.php
    $colors = array('Red', 'Blue', 'Green', 'Yellow');
    // Ask the user the favorite color
    $dialog = $this->getHelperSet()->get('dialog');
    $colorIndex = $dialog->select(
    $output,
    'What color do you like?',
    $colors
    );
    // Writes the Output
    $output->writeln(
    sprintf('The color you like is %s.', $colors[$colorIndex])
    );
    

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34. formatter HELPER
    

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35. OUTPUT
    $formatter = $this->getHelperSet()->get('formatter');
    $formattedLine = $formatter->formatSection(
    'SomeSection',
    'Here is some message related to that section'
    );
    $output->writeln($formattedLine);
    $msg = array('Something went wrong');
    $formattedBlock = $formatter->formatBlock($msg, 'error');
    $output->writeln($formattedBlock);
    $msg = array('Custom Colors');
    $formattedBlock = $formatter->formatBlock($msg, 'bg=blue;fg=white');
    $output->writeln($formattedBlock);
    

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36. progress helper
    

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37. 05/50 [== ] 10%
    25/50 [============= ] 50%
    50/50 [============================] 100%
    $progress = $this->getHelperSet()->get('progress');
    $progress->start($output, 50);
    $i = 0;
    while ($i++ < 50) {
    $progress->advance();
    }
    $progress->finish();
    OUTPUT
    

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38. table helper
    

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39. $table = $this->getHelperSet()->get('table');
    $table
    ->setHeaders(array('Color', 'HEX'))
    ->setRows(
    array(
    array('Red', '#ff0000'),
    array('Blue', '#0000ff'),
    array('Green', '#008000'),
    array('Yellow', '#ffff00')
    )
    );
    $table->render($output);
    OUTPUT
    

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40. command events
    

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41. • command - before run
    • exception - on exceptions
    • terminate - before return exit code
    the events
    

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42. testing Commands
    

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43. public function testCacheClear()
    {
    $application = new Application();
    $application->add(new CacheClearCommand());
    // Mock the DialogHelper to skip interact
    // ...
    $command = $application->find('cache:clear');
    // Add Mock to command
    $commandTester = new CommandTester($command);
    $commandTester->execute(array(
    'command' => 'cache:clear',
    'directory' => './cache'
    ));
    $this->assertFileNotExists($filename);
    }
    

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44. // Symfony/Component/Console/Tester/CommandTester.php
    class CommandTester
    {
    private $command;
    private $input;
    private $output;
    public function __construct(Command $command){..}
    public function execute(array $input, array $options=array()){..}
    public function getDisplay($normalize = false){..}
    public function getInput(){..}
    public function getOutput(){..}
    }
    command tester
    

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45. $ ./vendor/bin/phpunit
    

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46. dependency injection
    in your application
    

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47. Application
    Container
    CacheClearCommand
    FileSystem
    Finder
    Services
    setContainer(...)
    getContainer()
    addCommand()
    ...
    Other Commands
    

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48. namespace Symfony\Component\DependencyInjection;
    interface ContainerAwareInterface
    {
    public function setContainer(
    ContainerInterface $container = null
    );
    }
    container aware interface
    

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49. // DCSG/Application.php
    class Application extends BaseApplication
    implements ContainerAwareInterface
    {
    private $container;
    public function setContainer(..){..}
    public function getContainer(){..}
    }
    implement in the application
    

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50. // DCSG/Command/CacheClearCommand.php
    // ...
    $container = $this->getApplication()->getContainer();
    $fs = $container->get('filesystem');
    $finder = $container->get('finder');
    $files = $finder->in($cacheDir);
    $fs->remove($files);
    // ...
    usage in the command
    

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51. http://goo.gl/h0Xcfe
    http://symfony.com/doc/current/components/process.html
    Long running processes
    resources
    http://symfony.com/doc/current/components/console/index.html
    http://symfony.com/doc/current/cookbook/console/index.html
    http://symfony.com/doc/current/cookbook/service_container/index.html
    http://symfony.com/doc/current/components/dependency_injection/index.html
    Symfony2 Docs
    Cron jobs
    http://www.cyberciti.biz/faq/how-do-i-add-jobs-to-cron-under-linux-or-unix-oses/
    Source Code
    https://github.com/danielcsgomes/phplx-how-to-build-console-app
    https://github.com/symfony/Console
    

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52. @danielcsgomes | me@danielcsgomes.com | http://danielcsgomes.com
    Photo by Jian Awe © http://www."ickr.com/photos/qqjawe/6511141237
    Please give feedback:
    https://joind.in/9615
    Questions?
    

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