Execute a Drush command across all domains

Awesome. Check for typos in the comments though. I saw at least one.

I thought about this a little more. This is only useful if you are using different cache tables per domain, correct?

Then it should be a drush command for domain_prefix.

Abstracting that to drush domain-command FOO is very desirable. If it works reliably.

6.x is closed to new features. This has to go in 7.x.3.

I suppose the only real use-case for this is alternate caching (such as Views provides) and table prefixing. In general I don't see much utility here.

Here's a re-roll of #12 for 7.x-3.x with a few comment style improvements.

@agentrickard: Or is there an easier way to clear the cache tables of all domains?

Patch #14 for 7.x-3.x works fine for me.

In some installations, the used drush_shell_exec_interactive() command may issue this error:

sh: /usr/share/pear/drush/drush.php: Permission denied

A workaround may consist in giving exec permission to that file:

sudo chmod +x /usr/share/pear/php/drush/drush.php

Is there any way to avoid that error other than file permissions?

For me is fine to give Execute rights for Drush.
I just have one small improvement to add, only run it for Active domains. Please see the attached.

I had this problem in a shared environment. To avoid the permissions error caused by drush_shell_exec_interactive() you can write a custom Drush command in a modulename.drush.inc and use drush_invoke_process instead.

function drush_weekly_menu_send_all() {
  // As domain configuration can only be initialized during the Drush bootstrap
  // we need to assemble and execute a new Drush shell command on each domain.

  // Execute the command for each domain
  foreach (domain_domains() as $domain) {
    drush_print('[' . $domain['subdomain'] . '] Sending newsletters...');

    // Execute the command.
    drush_invoke_process('@self', 'weekly-menu-send', array(), array('uri' => $domain['scheme'] . '://' . $domain['subdomain']));
  }
}

Dion't forget the info hook:

/**
 * Implements hook_drush_command().
 */
function mymodule_drush_command() {
  $items = array();

  $items['weekly-menu-send-all'] = array(
    'description' => "Sends out the weekly menu for all domains.",
    'callback' => 'drush_weekly_menu_send_all',
    'drupal dependencies' => array('mymodule'),
  );

  return $items;
}