META Tags

First look through the list of modules to make sure it doesn't already exist. If not then the best thing to do is make a module. This could be done by editing your theme, but since this doesn't affect the look of the page (I would consider meta tags to be content) then it really doesn't belong there.

First, get started on your module by implementing some required hooks like _help. If you want to make the meta tag contents configurable via a web interface implment the _settings hook.

Now we want to actually put stuff in the header. The _init hook is a good place to do this sinc eit will be executed once for each page view. Just call drupal_set_html_head('meta tags go here') to put meta tags or anything else in the html head element. For only the front page use an if statment like: if ($_GET['q'] == variable_get('site_frontpage', 'node'))

If you did implement the _settings hook then you can access those settings the same way you did to prefill that page with the form values, using variable_get.

If you think you made something worthy of being seen by others then save it in the contributions CVS repository.

There was a keywords.module for older Drupal version and I have hacked it to work with 4.4.x. It seems to work for me at least.

function keywords_help($section) {
  $output = '';
  switch ($section) {
    case 'admin/help#keywords':
    case 'admin/system/modules/keywords':
      $output = "Search engines often use these <a href=\"http://www.w3.org/TR/1998/REC-html40-19980424/struct/global.html#h-7.4.4\">META</a> keywords to determine what topics are discussed at your site. The keywords that you choose do affect their relevance rankings, so some consideration to these keywords is wise.<br /><br />Tags beyond the META tag are also allowed here. In fact, this is a good place to add any tags like script, object, link, and others which are <a href=\"http://www.w3.org/TR/1998/REC-html40-19980424/struct/global.html#h-7.4.1\">allowed in the HEAD section of a web page</a>.";
      break;
    case 'admin/system/modules#description':
      $output .= t("Manage the meta tags outputted by drupal web pages.");
      break;
  }
  return $output;
}  

function keywords_perm() {
  return array("administer keywords");
}

function keywords_settings() {
  $output .= form_textarea(t("Keywords"), "keywords_meta", variable_get("keywords_meta", ""), 90, 6, t("The Meta tags which should be inserted into all web pages."));
  return $output;
}

function keywords_init() {
  if (variable_get("keywords_meta", "")) {
    drupal_set_html_head(variable_get("keywords_meta", ""));
  }
}