How to write and use config files in Zend Framework 2 - php

Question

Hi,
In Zend Framwork 1, I used to have an application\configs\appsettings.xml, where I used to store params and values like hostnames for Rest API URLs, debug settings and other application specific settings for dev, test and prod environments. This registry was available to me across all controllers and models and was created in index.php
$applicationEnvironment = 'development';
$config = new Zend_Config_Xml( APPLICATION_PATH . '/configs/appsettings.xml',
$applicationEnvironment, true );
Zend_Registry::set( 'config', $config );
How do I achieve similar thing in Zend Framework 2?
Thanks

Answer 1

There is no such thing as a Registry in ZF2 because it is kind of an anti pattern. It's just a fancy substitution for global variables, which can cause all sort of unwanted side effects in your application.
In ZF2 you have the serviceManager and this allow to cleanly inject all your dependencies into your controllers/models/services. All config files in the config/autoload directory are automaticaly merged into one single array by ZF2 and you can retrieve this from the service manager using $serviceLocator->get('Config'). Whenever you need to use configuration in your controller just create a serviceFactory and inject the config.
class FooController
{
protected $config;
public __construct($config)
{
$this->config = $config;
}
public barAction()
{
//use $this->config
}
}
class Module
{
public function getControllerConfig()
{
return array(
'factories' => array(
'fooController' => function(ControllerManager $cm)
{
$sm = $cm->getServiceLocator();
$config = $sm->get('Config');
$controller = new FooController($config);
return $controller;
},
),
);
}
}
For sake of simplicity the factory above is defined as a closure, but I'd suggest to create a seperate factory class. There are many resources which explain how to do that.
In this example we are injecting the complete configuration, but depending on your use case it will generally be better to only inject the config keys you need.
Alternatively you can wrap certain config values into a dedicated config object with explicit getters and setters and inject this into your controller. Zend\StdLib\AbstractOptions can help you.

Answer 2

If you wish to work with config files and you dont have access to the Service Manager or you wish to write content to it, you can use Zend\Config
To read from, you can do something like:
$config = new Config(include 'config/autoload/my_amazing_config.global.php');
$details = $config->get('array_key')->get(sub_key)->toArray();
To write to, you can do:
// Create the config object
$config = new Zend\Config\Config(array(), true);
$config->production = array();
$config->production->webhost = 'www.example.com';
$config->production->database = array();
$config->production->database->params = array();
$config->production->database->params->host = 'localhost';
$config->production->database->params->username = 'production';
$config->production->database->params->password = 'secret';
$config->production->database->params->dbname = 'dbproduction';
$writer = new Zend\Config\Writer\Xml();
echo $writer->toString($config);
The class support ini, xml, phpArray, json, yaml
You can read more at:
http://framework.zend.com/manual/2.2/en/modules/zend.config.introduction.html