Drupal 7 – Hook Execution Order

Although not specified explicitly anywhere, browsing through the code in the function “module_implements” gave me the hint that changing the order in which hooks are called is possible.

Here’s that snippet

 // Allow modules to change the weight of specific implementations but avoid
 // an infinite loop.
 if ($hook != 'module_implements_alter') {
 drupal_alter('module_implements', $implementations[$hook], $hook);
 }

All that needs to be done is to implement the hook hook_module_implements_alter specified here. Effectively by re-ordering the list of modules, you also change the order in which the hooks are called.

Here’s how I did it,

function mymodule_module_implements_alter(&$module_list, $context){
 if($context === "node_insert"){
 $temp = $module_list['mymodule'];
 // Removing the mymodule key/value
 unset($module_list['mymodule']);
 // Adding the mymodule key value as the last member in the list
 $module_list['mymodule'] = $temp;
 }
}

One point to remember is to declare the “module_list” variable as a reference variable with the “&”, or you’ll be modifying a local variable 🙂
Thats it. Done!