I would like to be able to trap when a particular message is sent via drupal_set_message

Question

I would like to be able to trap when a particular message is sent via drupal_set_message like: "•Article john mitchell article800 has been reverted back to the revision from Tue, 05/28/2013 - 10:03." After the message is sent that matches my criteria then I would like to send an email. I know how to send emails within hooks/php but I need to know how to trap for a particular message so that I know to send this email. Are their any hooks that could use to trap for this occurrence?

Answer 1

In Drupal 6, messages are themed for display via...

function theme_status_messages($display = NULL) {
  $output = '';
  foreach (drupal_get_messages($display) as $type => $messages) {
    $output .= "<div class=\"messages $type\">\n";
    if (count($messages) > 1) {
      $output .= " <ul>\n";
      foreach ($messages as $message) {
        $output .= '  <li>'. $message ."</li>\n";
      }
      $output .= " </ul>\n";
    }
    else {
      $output .= $messages[0];
    }
    $output .= "</div>\n";
  }
  return $output;
}

In Drupal 7, they are themed similarly via...

function theme_status_messages($variables) {
  $display = $variables['display'];
  $output = '';

  $status_heading = array(
    'status' => t('Status message'),
    'error' => t('Error message'),
    'warning' => t('Warning message'),
  );
  foreach (drupal_get_messages($display) as $type => $messages) {
    $output .= "<div class=\"messages $type\">\n";
    if (!empty($status_heading[$type])) {
      $output .= '<h2 class="element-invisible">' . $status_heading[$type] . "</h2>\n";
    }
    if (count($messages) > 1) {
      $output .= " <ul>\n";
      foreach ($messages as $message) {
        $output .= '  <li>' . $message . "</li>\n";
      }
      $output .= " </ul>\n";
    }
    else {
      $output .= $messages[0];
    }
    $output .= "</div>\n";
  }
  return $output;
}

so I'd imagine copying the appropriate function into your theme's template.php and naming it YOURTHEME_status_messages(...) along with some suitable regexing or strposing inside would do the trick pretty directly.