All you need to build large scale applications on distributed architecture using different programming language.

1. Nemanja Krivokapić
Software Engineer @ PSTech
@NemanjaKr | LinkedIn
PHP &
Gearman
All you need to build large
scale web application

2. What is Gearman?
 Generic
Application Framework
 Job Server
 Client / Worker API
 Multi-platform and multi-language API
support
 Support priorities

3. How does it work?

4. Multi-server configuration

5. Jobs vs. Tasks
 Matter
of perspective
 Client delegates task to the server
 Job server delegates jobs to the workers

6. Supported platforms and
languages
 Platforms:
Unix/Windows
 Languages supported:




PHP
Java
C/C++
NodeJS, Python, Go, Lisp...

7. Gearman server installation
tips
 Don’t
use Ubuntu package for gearman
server (outdated and doesn’t work with
current PHP PECL extension)
 Build it from source:
https://launchpad.net/gearmand
 Run: gearmand --deamon

8. Server configuration
 All
config params are supplied through
command line
 Important ones:





--port=XXX (default 4730)
--deamon
--job-retries (default NO LIMIT!)
--queue-type (default builtin, not persistent)
--listen (default INADDR_ANY)
 Use
--help

9. PHP Gearman
implementation
Yeah – this is cool but HOW CAN I USE IT?

10. Little bit of shell 
 Prerequisite:
libgearman (if built from source –
already included)
 PEAR (apt-get install php-pear)
 PECL (pear install pecl)*
 pecl install gearman
 Tell PHP to use gearman client/worker API extension
( extension=gearman.so in php.ini)
* For proxy: pear config http_proxy http://

11. Provided classes
 GearmanClient
 GearmanTask
 GearmanWorker
 GearmanJob
 GearmanException

12. GearmanClient
 Used
for communication with Job Server
from your application
 Foreground jobs (doHigh, doNormal,
doLow)
 Background jobs (doHighBackground,
doBackground, doLowBackground)
 Tasks (replace do* with addTask*)
 addTask* returns GearmanTask object,
do* returns string!

13. GearmanWorker
 We
use it to connect our worker script to
Job Server and wait for job
 addFunction(string
$function_name
, callable $function)
 work()
 Callable provided will receive an
GearmanJob object as argument

14. Running tasks in parallel
 You
can stack as many tasks using
addTask method of GearmanClient.
 They will all be executed in parallel when
you call runTasks (if there’s enough
workers available)
 Notice: Using do* methods will execute
the task immediately

15. Client callbacks for workers
events
 When
running foreground tasks you can register
callbacks using methods of GearmanClient using
methods:





setCompleteCallback,
setCreatedCallback,
setDataCallback,
setExceptionCallback,
setFailCallback
 They
all take single argument – callable object
which will receive GearmanTask object as an
argument.

16. SupervisorD – keep it running
 PHP
worker script will wait for job, do it and die.
 Supervisord – Process Control System*
 apt-get install supervisor
 Create configuration file in
/etc/supervisor/supervisord.conf
 sudo service supervisor
* Project homepage: http://supervisord.org/

17. SupervisorD alternative
 GearmanManager
 Easier
to setup
 PHP wrapper around GearmanWorker
 https://github.com/brianlmoon/Gearman
Manager

18. Relevant links




PHP Examples:
http://www.php.net/manual/en/gearman.examples.
php
Gearman Job Server documentation:
http://gearman.org/documentation/
Cool tutorials to get started with Gearman on
Ubuntu:
http://blog.andyburton.co.uk/index.php/201212/compiling-gearman-with-mysql-persistent-storageon-ubuntu-12-04-precise/
http://blog.andyburton.co.uk/index.php/201212/gearman-0-41-with-mysql-persistent-storage-andphp-pecl-0-8-3-with-gearmanmanager-on-ubuntu12-04/

19. Questions?
The End 