I've searched around the issues but didn't find anything.
This sounds weird, but my hook_menu is only being called with !$may_cache !! How is it possible?

I've checked again and again, refreshed the cache_menu table, revisited admin/build/menu... nothing. My hook_menu is simply not being passed TRUE in $may_cache.

Here's my hook_menu, very simple (using Drupal 5.1):

<?php
function takeit_menu($may_cache){
  $items = array();
  // I've watchdoged here - only got results for !$may_cache
  if($may_cache){
    // I've watchdoged here - no results!
    if(arg(0)=='takeit' && is_numeric(arg(1))){
      $items[] = array(
        'path'=>'takeit',
        'title'=>t('Take Thread'),
        'callback'=>'takeit_take_thread',
        'access'=>TRUE,
        'type'=>MENU_CALLBACK
      );
    }
  }
  return $items;
}

?>

Comments

webchick’s picture

webchick
she/they
Primary language English
Location Vancouver 🇨🇦
commented
Category: bug » support
Status: Active » Closed (works as designed)

This is by design.

$may_cache == TRUE is for static menu items, such as 'admin/settings/foo'. These paths are predictable and always point to the same place, so they are stored in the menu_cache table. The only time code in a $may_cache block is run is when a menu_rebuild() is executed, which is when new modules are enabled/disabled and after the cache is cleared.

$may_cache == FALSE is for dynamic menu items, such as 'user/1/edit'. Because you don't know ahead of time which path you'll actually be looking at, you stick these in a if (!$may_cache) so they check the current page and determine whether they need to activate or not.

Because your path is dymanic (takeit/[some number]), it belongs in a (!$may_cache) block.

z.stolar’s picture

z.stolar commented

So maybe the documentation is wrong? Here's a quote from http://api.drupal.org/api/5/function/hook_menu :

Drupal will call this hook twice: once with $may_cache set to TRUE, and once with it set to FALSE.

I understand from this line that each module that implements hook_menu, will get visited twice during a page load.
But it doesn't.

In the code above, the path is not dynamic. it is 'path'=>'takeit', I only do a check, to verify I'm looking at the right page, so the path won't be declared where it is not needed. I understand this might be a mistake, since cached items are always present, regardless of the current url.

However, I also mentioned I erased the cache, and visited admin/build/menu, and nothing helped - my hook was not called with $may_cache == TRUE (notice the watchdog position), that's why I suspect it's a bug, and not the usual behavior of Drupal.

I should put some watchdogs elsewhere to see what happens in other modules. This would be smarter than just shouting Drupal is broken. I'll report my findings here.

jjweiner’s picture

jjweiner commented

I wonder if the "if" statement is causing the problem:

<?php
if(arg(0)=='takeit' && is_numeric(arg(1))){
?>

Perhaps a work-around is to put the business logic in the "takeit_take_thread" function and pass it arg(1):

<?php
function takeit_menu($may_cache){
  $items = array();
 
  if($may_cache){
      $items[] = array(
        'path'=>'takeit',
        'title'=>t('Take Thread'),
        'callback'=>'takeit_take_thread',
        'callback arguments' => array(arg(1)),
        'access'=>TRUE,
        'type'=>MENU_CALLBACK
      );
  }
  return $items;
}
?>

Then the function could determine if arg(1) is numeric:

<?php
function takeit_take_thread($arg = NULL){

if (is_numeric($arg))){
   //do something
  }
}
?>
nevets’s picture

nevets commented

hook_menu is only called with $may_cache set to TRUE when a module is enabled or the admin page for menu is visited. During a page load $may_cache is always false.

jjweiner’s picture

jjweiner commented

If you empty the cache (I usually do this with the devel module) if should force the menu $items array to reload when $may_cache is TRUE.