Laravel Artisan Queue Ensurer - Set a cron job to run this file periodically to ensure that Laravel's queue is processing all the time. If the queue listener stopped, restart it!

queue-ensure.php

<?php

function runCommand ()
{
    $command = 'php artisan queue:listen > /dev/null & echo $!';
    $number = exec($command);
    file_put_contents(__DIR__ . '/queue.pid', $number);
}

if (file_exists(__DIR__ . '/queue.pid')) {
    $pid = file_get_contents(__DIR__ . '/queue.pid');
    $result = exec('ps | grep ' . $pid);
    if ($result == '') {
        runCommand();
    }
} else {
    runCommand();
}

A made a simple solution for this (Laravel 5.5 dev).

I created a new function, that checks if the process is running.
Then, a simple if-condition arround the command does the thing

        // start the queue daemon, if its not running
        if ( !$this->osProcessIsRunning('queue:work') ) {
            $schedule->command('queue:work')  ->everyMinute();
        }

I put the new function right in app/Console/Commands/Kernel.php:

    /**
     * checks, if a process with $needle in the name is running
     *
     * @param string $needle
     * @return bool
     */
    protected function osProcessIsRunning($needle)
    {   
        // get process status. the "-ww"-option is important to get the full output!
        exec('ps aux -ww', $process_status);

        
        // search $needle in process status
        $result = array_filter($process_status,
            function($var) use ($needle)
            {   return strpos($var, $needle); });


        // if the result is not empty, the needle exists in running processes
        if (!empty($result)) {
            
            return true;
        }

        return false;
    }

Edit: Execution time on my dev-machine is 3-4ms.

Thanks kohlerdominik!,
It's working perfectly.

@kohlerdominik solution work's great! Thanks!

@kohlerdominik perfect solution. Thanks!

What's the purpose of & echo $! here?

For shared hosted with disabled exec functions, I made a shell script.

Cron job:
* * * * * cd /path/to/public_html && /usr/bin/sh artisan.call.sh >> /dev/null 2>&1

How work

• Check for folder /storage/queue.lock/
• If not exists, call artisan queue:work and create the folder, otherwise do nothing.
• Check for file /storage/.queue-restart, if exists, run artisan queue:restart and remove folder /storage/queue.lock/

When run artisan queue:restart the script must exit and auto remove queue.lock folder, next time call artisan queue:work.

#!/bin/bash

FULL_PATH_TO_SCRIPT="$(realpath "$0")"
SCRIPT_DIRECTORY="$(dirname "$FULL_PATH_TO_SCRIPT")"
LOCKFILE="$SCRIPT_DIRECTORY/storage/queue.lock"
LOGFILE="$SCRIPT_DIRECTORY/storage/logs/queue.log"
QUEUE_RESTART_FILE="$SCRIPT_DIRECTORY/storage/logs/.queue-restart"

d=$(date '+%F %T')

log()
{
    echo '=============================================================================================' >> "${LOGFILE}"
    echo "$d" >> "${LOGFILE}"

    if [ "$1" ]; then
      echo "$1" >> "${LOGFILE}"
    fi
}

clean_log()
{
    truncate -s 0 "${LOGFILE}"
}

remove_lock()
{
    log "Removing lock file $LOCKFILE… exiting"
    rmdir "$LOCKFILE"
}

another_instance()
{
    log "Lock file $LOCKFILE exists… exiting"
    exit 1
}

run_artisan()
{
      if [ "$1" ]; then
        (php ${SCRIPT_DIRECTORY}/artisan $1)
      fi
}

if ! mkdir "${LOCKFILE}" 2>/dev/null; then
    another_instance
    exit 1
fi

if [ -f "${QUEUE_RESTART_FILE}" ]; then
    rm "$QUEUE_RESTART_FILE"
    log "restarting queue"
    run_artisan "queue:restart"
    remove_lock
    exit 1
fi

trap remove_lock QUIT INT TERM EXIT
clean_log
log "runing php \"${SCRIPT_DIRECTORY}/artisan queue:work"\"
run_artisan "queue:work"

@alvaro-canepa thanks this work me

I also need the shell-script variant... pgrep allows to use it without the pid file.
However you can only run one instance of php artisan queue:work

I use pgrep to only search for the artisan queue:work since my provider uses an alias for php.

#!/bin/bash

# Check if "artisan queue:work" is running
if pgrep -f "artisan queue:work" > /dev/null
then
    echo "queue:work is already running."
    exit 1
else
    echo "Starting queue:work..."
    nohup php artisan queue:work > /dev/null 2>&1 &
    echo "queue:work started."
fi

@CodeAndWeb looks nice, more clean than my code!

Thanks to share