How to use Memcached in Doctrine2 / ZF2? - php

Question

I have set up my code / directories / configuration as outlined in this article: http://www.jasongrimes.org/2012/01/using-doctrine-2-in-zend-framework-2/
So my config file looks something like:
<?php
namespace Game;
return array(
// <snip>
// Doctrine config
'doctrine' => array(
'driver' => array(
__NAMESPACE__ . '_driver' => array(
'class' => 'Doctrine\ORM\Mapping\Driver\AnnotationDriver',
'cache' => 'array',
'paths' => array(__DIR__ . '/../src/' . __NAMESPACE__ . '/Entity')
),
'orm_default' => array(
'drivers' => array(
__NAMESPACE__ . '\Entity' => __NAMESPACE__ . '_driver'
)
)
)
),
);
Now, what do I need to set/change to make Doctrine use Memcached as its caching backend? I have searched a lot on Google, but other than in this question, where it says they got it working (but not how), I have not been able to find anything.

Answer 1

They had posted the official way to support it here

Answer 2

forget the previous answer. after spending hours tracing the errors i found that doctrine looks for "doctrine.cache.instance" the value there should be a string referencing the service you set up in the service manager.
however, due to a bug in the doctrine code base the config is never retrieved. i will submit this to github later.
but the good news is that when no "doctrine.cache.instance" is given the alias "my_memcached_alias" is used.
so the above code can easely be fixed and the awkward hacks removed from the doctrine source.
(note: i left the doctrine.cache config in for future compatibility and showing the proper way to set the instance alias)
module.config.php
'doctrine' => array(
'driver' => array(
__NAMESPACE__ . '_driver' => array(
'class' => 'Doctrine\ORM\Mapping\Driver\AnnotationDriver',
'cache' => 'memcached',
'paths' => array(__DIR__ . '/../src/' . __NAMESPACE__ . '/Entity'),
),
'orm_default' => array(
'drivers' => array(
__NAMESPACE__ . '\Entity' => __NAMESPACE__ . '_driver',
),
),
),
'cache' => array(
'instance' => 'my_memcached_alias',
),
),
'service_manager' => array(
'factories' => array(
'my_memcached_alias' => function() {
$memcached = new \Memcached();
$memcached->addServer('localhost', 11211);
return $memcached;
},
),
),
i hope you have already found a solution by now that doesnt involve a framework modification, but for al the people still searching for answers this will definetly help
Edit:
After Many headaches I found out that th config should be doctrine.cache.memcache.instance
second edit:
here's the correct code
'cache' => array(
'memcache' => array(
'instance' => 'memcacheService',
),
),

Answer 3

I had some trouble to get it working and I only have a temporary workaround as I needed to modify the Doctrine ORM Module itself.
First, set the cache to memcache: 'cache' => 'array', to 'cache' => 'memcache', in your config above.
Then, define a service factory to create the memcache instance. You can do this in a module class:
NOTE: This example bases on memcache, not memcacheD. But it should be the same for memcached.
function getServiceConfig()
{
return array(
'factories' => array(
'memcache' => function(ServiceManager $sm) {
$memcache = new \Memcache(); // .. do some configuration and connect
return $memcache;
}
)
);
}
The last step is to modify the Doctrine ORM Module. Otherwise, it won't create the instance and throws an error.
In DoctrineModule/Service/CacheFactory.php l61 :
$cache->setMemcache($options->getInstance());
Becomes:
$cache->setMemcache($sl->get($options->getInstance()));
(In your case, do this for line 64.) Or find another way to inject a memcached instance into $options. Be aware that this should only be a workaround and be fixed as soon as possible. Otherwise, you'll have trouble updating the module.
Hope this helps.

Answer 4

We don't need to change core Doctrine ORM module source.
Change factories to:
return array(
'factories' => array(
'my_memcache_alias' => function(ServiceManager $sm) {
$memcache = new \Memcache(); // .. do some configuration and connect
return $memcache;
}
)
);

Answer 5

First of all install the memcached php extension.
~ # > aptitude install php5-memcached
After that you will need to configure the memcached servers parameters
//app/config/parameters.yml
parameters:
...
memcache_hosts:
-
dsn: 127.0.0.1
port: 11211
Next we need to create some services
services:
memcached:
class: Memcached
calls:
- [ addServers, [%memcache_hosts%] ]
doctrine.cache.memcached:
class: Doctrine\Common\Cache\MemcachedCache
calls:
- [ setMemcached, [ #memcached ] ]
After that we will need to add some configuration to config.yml
//app/config/config.yml
...
doctrine:
...
orm:
entity_managers:
default:
...
metadata_cache_driver:
type: service
id: doctrine.cache.memcached
query_cache_driver:
type: service
id: doctrine.cache.memcached
result_cache_driver:
type: service
id: doctrine.cache.memcached
Now We can use Memcached to cache our queries as the Doctrine Doc explains.
Also we have three symfony commands to clear the doctrine cache
$> php app/console doctrine:cache:clear-metadata
//Clears all metadata cache for an entity manager
$> php app/console doctrine:cache:clear-query
//Clears all query cache for an entity manager
$> doctrine:cache:clear-result
//Clears result cache for an entity manager
I have extracted these steps from:
https://blog.42mate.com/implementing-doctrine-caching-with-memcached-in-symfony-2/