php-sysv-ipc-message-queue

php sysv ipc message queue wrapper

IPC Message Queue for php

SysV IPC Message queue is available as php function. This package is Object Class wrapping msg_send.

This repository wrap function and frequently appearing Usage.

Installing

from Packagist.

composer require takuya/php-sysv-ipc-message-queue

from GitHub.

name='php-sysv-ipc-message-queue'
composer config repositories.$name \
vcs https://github.com/takuya/$name  
composer require takuya/$name:master
composer install

Examples.

• Initialize and push
• Dont forget remove Queue.
• Save and Load for system ShutDown.
• Multi process (inter process).

Initialize and push to Queue

initialize and send data to queue.

$q = new IPCMsgQueue('my-named-queue');
$msg = 'random string';
$q->push($msg);

Since msg_send is supporting serialize. we can push everything.

$q = new IPCMsgQueue('my-named-queue');
// send array 
$msg = ['a'=>1];
$q->push($msg);
// send object
$obj = new stdClass();
$obj->name = 'takuya';
$msg = $obj;
$q->push($msg);

We can get queue message as is sent.

$q = new IPCMsgQueue('my-named-queue');
$arr = ['a'=>1];
$q->push($msg=$arr);
// retrieve data as send.
$result = $q->pop();
// same to send
$arr == $result #=> true

Notice, by serialize() , message size increased.(over 1024, large bytes);

## large bytes 
$msg = str_rand(1024);
$q = new IPCMsgQueue('my-named-queue');
$q->push($msg);
// will be not same to $msg.
$result = $q->pop();
// to get same data,specify large size.
$result = $q->pop(null,strlen(serialize($msg)));// will be 10 byte larger.

I wrote this class , suppose to be used simple message. large size (>1024) is un-usual way.

Don't forget to remove queue never used.

use destroy() to remove queue.

require_once 'vendor/autoload.php';
use Takuya\PhpSysvMessageQueue\IPCMsgQueue;
$q = new IPCMsgQueue('my-named-queue');
$q->push('message');
$q->pop();
$q->destroy();

Or use ipcs -q, ipcrm command to remove unnecessary used queue.

ipcs -q | grep takuya
ipcrm --queue-key 0x1234567
## you can delete at once.
ipcs -q | grep takuya | grep -oE '0x[a-f0-9]+' | xargs -I@ ipcrm --queue-key @

Queue will be remains unless explicitly deleted.

save and load when OS shutdown.

SysV IPC Message will be lost after shutdown. to prevent lost , try save and load messages.

Before shutdown

$q = new IPCMsgQueue('my-named-queue');
// push some messages
$q->push('msg');
$q->push('msg');
$q->push('msg');
// save before shutdown.
$q->save('path/to/permanent/file');

After restart

$q = new IPCMsgQueue('my-named-queue');
// load after system restarted.
$q->load('path/to/permanent/file');
// can read data 
$q->pop()#=>'msg';
$q->pop()#=>'msg';
$q->pop()#=>'msg';

Multi Process (IPC)

Multi process (inter process). same name same queue.

consumer.php (worker)

<?php
require_once 'vendor/autoload.php';
use Takuya\PhpSysvMessageQueue\IPCMsgQueue;
$name = 'my-queue';
$q = new IPCMsgQueue($name);
register_shutdown_function(fn()=>$q->destroy());
while($q->available()){
  $body = $q->pop();// blocking io
  var_dump($body);
}

producer.php ( maker )

require_once 'vendor/autoload.php';
use Takuya\PhpSysvMessageQueue\IPCMsgQueue;

$name = 'my-queue';
$q = new IPCMsgQueue($name);

foreach (range(0,10) as $cnt){
  $q->push('job:'.$cnt);
  sleep(10);
}

run

php consumer.php & # run in background.
php producer.php

Comparison

PHP's IPC System Message Queue function msg_send has auto serialization, This is very useful.

Compare SysV IPC Queue to another shared way. IPC Queue is easy to use.

type	advantage to SysV mesg func	dis-advantage to sysV func
tcp://	can listen another pc	Manual serialization, data structure design, read size needs manually adjustment
Shared-Memory and Semaphore	can share same data	Be careful of R/W timming (Semaphore), manually blocking, Queue Data structure needs fully considered, manually serialization
File and flock()	data persistence is easy	Be careful of R/W timming(flock), Data structure fully considered, manually serialization
sqlite / sql	Easy to data persistence	Needs SQL knowledge or O/R mapper, manually serialization

PHP's SplQueue or SplStack cannot share data to another process, These require sql or file library to use.

In that reason, msg_send msg_receive is the easiest way to share Tasks.