what is the difference between disable module output and module active = true

Question

In magento I come to knew that we can disabel our module by two ways

1. By navigating in the Magento backend to System > Configuration > Advanced > Disable modules output we can easily disable certain modules.
2. In the directory app/etc/modules, by changing the active-tag from true to false.

May I know what is the exact difference in these two technic? Its very help if anyone give more detailed Answer.

Answer 1

1. System > Configuration > Advanced > Disable Modules Output will not actually disable that module. It work as the name suggest, disable modules output.

   When you look at

   abstract class Mage_Core_Block_Abstract
   

   In

   final public function toHtml()
   {
       Mage::dispatchEvent('core_block_abstract_to_html_before', array('block' => $this));
       if (Mage::getStoreConfig('advanced/modules_disable_output/' . $this->getModuleName())) {
           return '';
       } 
   
   // It is checking If its in disabled mode then just return blank output
   .......
   }
   

2. While app/etc/modules completely disabled module

Answer 2

1. By navigating in the Magento backend to System > Configuration > Advanced > Disable modules output we can easily disable certain modules.

   -- That means module will not render, doesn't send output to the screen but your module execute. Take a look app/code/core/Mage/Core/Block/Abstract.php -> toHtml

   if (Mage::getStoreConfig('advanced/modules_disable_output/' . $this->getModuleName())) { return ''; }

2. In the directory app/etc/modules, by changing the active-tag from true to false.

   ---- true/false define your module will be load or skip. Take a look app/code/core/Mage/Core/Model/Config.php -> loadModulesConfiguration

foreach ($modules as $modName=>$module) { if ($module->is('active')) { ------- } }

Answer 3

Configuration > Current Configuration Scope > Advanced > Advanced > Disable Module Output. This action only disables module output as it says. If your module uses, let’s say some Observer functionality to hook into some part of the system and does some overriding then those actions won’t be disabled.

To fully disable module, you need to go to module config file, like /etc/NAMESPACE_MyModule.xml, and set it’s active parametar to false, like:

< ?xml version="1.0"?>
<config>
<modules>
<NAMESPACE_mymodule>
<active>false</active>
<codepool>local</codepool>
</NAMESPACE_mymodule>
</modules>
</config>

Answer 4

When you just Disable Modules Output, it means the module will not render anything on the screen, in programming terms: the _toHtml() function will return nothing. Everything else (observers, rewrites, controllers) will still be executed.

Ideally, if you want to disable a module properly, set "Active" is to false, and make sure no other module is extending it.

Answer 5

"Disable modules output" only disables the block output defined by the extension. It does not skip execution of the module its code if, for example, it has observers defined.