ProcessManager.php

<?php


namespace ProcessManager;


use ProcessManager\db\DBManagerInterface;
use ProcessManager\process\ProcessAbstract;
use ProcessManager\process\ProcessInterface;
use ProcessManager\process\ProcessParent;

class ProcessManager extends ProcessParent
{
    /** @var integer number processes are running now */
    protected $nRunningProcesses;
    private   $isStopSignal = false;

    public function initSignalsHandlers()
    {
        pcntl_signal(SIGTERM, [$this, 'signalsHandlers']); //kill
        pcntl_signal(SIGINT, [$this, 'signalsHandlers']); //ctrl+c
        pcntl_signal(SIGHUP, [$this, 'signalsHandlers']); //restart process
//        pcntl_signal(SIGCHLD, [$this, 'signalsHandlers']);
    }

    public function signalsHandlers($signo, $signinfo)
    {
        echo PHP_EOL . ' --- process ' . $this->getProcessName() . ' got signal=' . $signo . ' and signinfo='
            . print_r($signinfo, true);

        switch ($signo) {
            case SIGINT:
            case SIGTERM:
            case SIGHUP:
                $this->isStopSignal = true;
                foreach ($this->getProcessRoulette() as $process) {
                    /** @var ProcessInterface|ProcessAbstract $process */
                    if ($process->isRunning()) {
                        $processPid = $process->getPid();
                        posix_kill($processPid, SIGTERM);
                        echo PHP_EOL . ' --- To process \'' . $process->getProcessName() . '\' sent TERMINATE signal';
                    }
                }
                break;
            default:
        }
    }


    public function start()
    {
        echo PHP_EOL . date('Y-m-d H:i:s') . ' PROCESS_MANAGER is started';
        $this->updateProcessPriority();

        $this->initSignalsHandlers();
        $this->loadState();

        if ($this->isStartNeeded() && !$this->isStopSignal) {//need run
            $this->setPid(getmypid())
                ->saveState();
            while (!$this->isStopNeeded() && !$this->isStopSignal) {
                $this->setLastUpdateDatetime(date('Y-m-d H:i:s'))
                    ->setRunningFlag(1)
                    ->saveState();
//                echo PHP_EOL . $this->getLastUpdateDatetime() . ' PROCESS_MANAGER is running';

                //calculate number of running processes before
                $nRunningProcesses = 0;
                foreach ($this->getProcessRoulette() as $process) {
                    /** @var ProcessInterface|ProcessAbstract $process */
                    $process->loadState();
                    if ($process->isRunning()) {
                        $nRunningProcesses++;
                    }
                }
                $this->nRunningProcesses = $nRunningProcesses;

                //Roulette starts from last not executed process
                foreach ($this->getProcessRoulette() as $process) {
                    /** @var ProcessInterface|ProcessAbstract $process */
                    if ($this->nRunningProcesses >= $this->getMaxRunningProcesses()) {
                        break;
                    }
                    try {
                        if ($process->isStartNeeded()) {
                            $pid = $this->forkProcess($process);
                            if ($pid > 0) {
                                $this->nRunningProcesses++;
                            }

                        } elseif ($process->isStopNeeded()) {
                            $s = posix_kill($process->getPid(), SIGTERM);
                            if (!$s) {
                                $process->setRunningFlag(0)
                                    ->saveState();
                            }
                        }
                    } catch (\Throwable $e) {
                        $msg = '"' . $e->getMessage() . '" ' . PHP_EOL . $e->getTraceAsString();
                        echo PHP_EOL . date('Y-m-d H:i:s') . ' process \'' . $process->getProcessName() . '\' got exception:'
                            . PHP_EOL . $msg;
                        $process->addErrorToList(date('Y-m-d H:i:s') . '   ' . $msg)
                            ->saveState();
                    }
                }

                //catch children signals
                $pid = 1;
                while ($pid > 0) {
                    $pid = pcntl_waitpid(-1, $pidStatus, WNOHANG);
//                    if ($pid > 0) {
//                        if (pcntl_wifexited($pidStatus)) {
//                            $code = pcntl_wexitstatus($pidStatus);
//                        } else {
//                        }
//                    }
                }

                sleep(1);
                pcntl_signal_dispatch();
                $this->loadState();
            }

            //init connect to db
            // get listeners list
            $this->setRunningFlag(0)
                ->saveState();
            echo PHP_EOL . date('Y-m-d H:i:s') . ' PROCESS_MANAGER is stopped';

        } elseif (// need stop
            $this->isRunning()
            &&  (
                $this->getLastUpdateDatetime() !== null
                && time() >= (strtotime($this->getLastUpdateDatetime()) + $this->getMaxLifetimeWithoutResults())
            )
            && $this->getExecutionStep() !== 0
            && ($this->getMaxNTriesOfRun() === 0 || $this->getNTriesOfRun() <= $this->getMaxNTriesOfRun())
        ) {
            echo PHP_EOL . date('Y-m-d H:i:s') . ' PROCESS_MANAGER is stopping';
            posix_kill($this->getPid(), SIGTERM);
            $this->setRunningFlag(0)
                ->saveState();
        } else {
            echo PHP_EOL . date('Y-m-d H:i:s') . ' PROCESS_MANAGER was run before';
        }
    }

    /**
     * clear parent resourses in child process
     *
     * @return void
     */
    public function clearParentResourcesAfterFork()
    {
        $this->setProcessesRoulette(null);
        $this->setDBManager(null);
    }
}