Best practice to make Config object available inside Controller and Model

Question

Hello,

On application start I'm creating Config object (Singleton). How could I make Config object be available inside Model and Controller? Should I pass Config object to constructor as method parametr or I should better use $this->config = Config::getInstance()? Any other methods?

Thank you

Answer 1

If Config is a Singleton, you can use pretty much any solution you'd like :

• Passing it as a parameter is not needed, as it's global
  • But passing is as a parameter can allow for dependancy injection -- which might help if you want some automated tests
• Storing it as a class property can be useful -- but it's not required either.

Generally, for that kind of object, I just use Config::getInstance() each time I need it, and don't store it in a class property.

But I guess this is a matter of personnal preferences...

Answer 2

I usually make it a instance singleton by means of Config::getInstance(), and add accesors in Environment#config (or Bootstrap#config , tutorials go with Bootstrap) and My_Top_Controller#config (this My_Top_Controller extends Zend_Controller and is the ancestor of all other controllers) and also add it to Zend_Registry via config key.

Answer 3

Singleton is essentially just fancy syntax for a global variable, and is as bad as globals are (and they are bad). Passing a parameter is the cleanest option as it creates no hard coupling between classes and allows for maximum flexibility. Another reasonable (but rather advanced) option is to use a dependency injection container, see for example this post.