how to add javascript with #attached and hook_page_alter

Question

I tried to add js to pages by means of #attached, as it seems to be the recommended way. From what I understand, this involves altering a render array. hook_page_alter seems to me like good candidate.

As per https://www.drupal.org/node/756722 (and answers below), I came with:

function MODULE_page_alter(&$page) {
  $my_path = drupal_get_path('module', 'MODULE' );
  $page ['#attached']['js'][] = array(
    'js' => array(
    'type'=>'file',
    'data' => $my_path . '/module_test.js'),
  );
}

The file does not get attached, though. If I use

drupal_add_js($my_path . '/module_test.js');

it does get attached (it's not a problem of the js file, access persmissions, etc.).

What is wrong?

PS. I asked a related, but apparently wrong-headed question here

Answer 1

The code that finally got it included an important change with regard to @AyeshK 's answer. The [attached] is not put at the top level if $page , but inside ['content'] or ['header'].

The adapted code from the Format#1 is now:

function MODULE_page_alter(&$page) {
  $my_path = drupal_get_path('module', 'MODULE' );
  $page ['content']['#attached']['js'][] = array(
    'type'=>'file',
    'data' => $my_path . '/module_test.js'
  );
}  

Answer 2

Your code is almost correct. However, when you have a numeric key in [#attached][js], and its value is an array, you must include the data key.

Format #1

function MODULE_page_alter(&$page) {
  $my_path = drupal_get_path('module', 'MODULE' );
  $page ['#attached']['js'][] = array(
    'type'=>'file',
    'data' => $my_path . '/module_test.js'
  );
}

Format #2

function MODULE_page_alter(&$page) {
  $my_path = drupal_get_path('module', 'MODULE' );
  $page ['#attached']['js'] = array(
    $my_path . '/module_test.js'
  );
}

Format #

function MODULE_page_alter(&$page) {
  $my_path = drupal_get_path('module', 'MODULE' );
  $page ['#attached']['js'] = array(
    $my_path . '/module_test.js' => array(
      'type' => 'file',
    ),
  );
}