WorkflowBundle/Command/LockWaitCommand.php

<?php

namespace WorkflowBundle\Command;

use Symfony\Bundle\FrameworkBundle\Command\ContainerAwareCommand;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use WorkflowBundle\Services\TaskLoggerService;

class LockWaitCommand extends ContainerAwareCommand
{

    protected function configure()
    {
        $this
            ->setName('lock:wait')
            ->setDescription('Lock wait command')
            ->setHelp('Lock wait command. Wait for lock a file. The lock can be either exclusive or shared')                
            ->addArgument('filename', InputOption::VALUE_REQUIRED, 'Filename')
            ->addOption('command', 'c', InputOption::VALUE_REQUIRED, 'Command to execute')
            ->addOption('dir', null, InputOption::VALUE_REQUIRED, 'Directory path file', '/tmp')
            ->addOption('timeout', null, InputOption::VALUE_REQUIRED, 'Timeout execution (ms)', 600)
            ->addOption('no-exclusive', 'no-e', InputOption::VALUE_NONE, 'No exclusive lock')
        ;
    }

    /**
     * @param InputInterface $input
     * @param OutputInterface $output
     */
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $filename = $input->getArgument('filename');
        $command = $input->getOption('command');
        $dir = $input->getOption('dir');
        $timeout = $input->getOption('timeout');
        $no_exclusive = $input->getOption('no-exclusive');
        if ($filename && $command) {
            $handle = $this->fopen($filename, $dir);
            if ($this->flock($handle, $command, $timeout, $no_exclusive)) {
                $output->writeln('<info>OK</info>');
            }
        } else {
            $output->writeln('<error>Enter a valid filename and command</error>');
        }
    }

    /**
     * @param string $filename
     * @param string $dir
     * 
     * @return resource
     */
    protected function fopen($filename, $dir)
    {
        // limpio el filename completo
        $invalid_chars = array(" ", '"', "'", "&", "\\", "?", "#", "$", "//");
        $delimiter = DIRECTORY_SEPARATOR;
        $dir_pieces = explode($delimiter, str_replace($invalid_chars, '', $dir));
        $filename_pieces = explode($delimiter, str_replace($invalid_chars, '', $filename));
        $last_filename_piece = array_pop($filename_pieces);
        
        $dir = $delimiter . implode($delimiter, array_filter(array_merge($dir_pieces, $filename_pieces)));
        $filename = $dir . $delimiter . $last_filename_piece;
        
        if (!file_exists($dir)) {
            mkdir($dir, 0777, true);
        }

        return fopen($filename, "w+");
    }
    
    /**
     * @param resource $handle
     * @param string $command
     * @param int $timeout
     * @param boolean $no_exclusive
     * 
     * @return boolean
     */
    protected function flock($handle, $command, $timeout = 600, $no_exclusive = false)
    {
        pcntl_signal(SIGALRM, function() {
            exit(1);
        });
        pcntl_alarm($timeout);
        $operation = LOCK_EX;
        if ($no_exclusive) {
            $operation = LOCK_SH;
        }
        if (flock($handle, $operation)) {
            $exit_code = $this->runProcess($command)['exit_code'];
        } else {
            echo 'No se pudo obtener el lock' . PHP_EOL;
            $exit_code = 1;
        }
        
        pcntl_alarm(0);
        pcntl_signal_dispatch();
        pcntl_signal(SIGALRM, SIG_DFL);
        
        flock($handle, LOCK_UN);
        fclose($handle);
        
        exit($exit_code);
    }
    
    
    /**
     * @param string $filename
     * 
     * @return array
     */
    protected function runProcess($filename)
    {
        /* @var $taskloggerService TaskLoggerService */
        $taskloggerService = $this->getContainer()->get('flowdat_tasklogger_service');
        
        return $taskloggerService->runProcess($filename);
    }

}