Adding multiple taxonomy terms to a single node programmatically

Question

I have the following iteration:

  foreach($category as $cat) {
              insert_term_if_not_exists($cat, 'tags');
              $term_tags = taxonomy_get_term_by_name($cat);
              $tid_tags = key($term_tags);
              $lang_tags = field_language('node', $node, 'field_tags');
              $node->field_tags[$lang_tags][0]['tid'] = $tid_tags;
            }
          }
       }
  node_save($node);

which relies on the following function to create non-existent taxonomy terms:

function insert_term_if_not_exists($term_name, $vocabulary_name) { 
  $vocabulary = taxonomy_vocabulary_machine_name_load($vocabulary_name);
  $matched_terms = taxonomy_get_term_by_name($term_name, $vocabulary->machine_name);
    if(empty($matched_terms)) {
      $term = new stdClass();
      $term->vid = $vocabulary->vid;
      $term->name = $term_name;
      taxonomy_term_save($term);
    } else {
      $term = array_shift($matched_terms);
    }
return $term;
}

This couple pieces of code work great to create new taxonomy terms (taken from $category array) and to associate a node with the last taxonomy term. And I need to add all of the taxonomy terms which went through iteration above to the node.

Looking everywhere to find proper instructions to add multiple taxonomy terms to a single node programmatically without much success. Hope someone here can point me to the right direction, thanks!

Answer 1

Finally I have a working code:

insert_term_if_not_exists($cat, 'tags');
              $term_tags = taxonomy_get_term_by_name($cat);
              $tid_tags = key($term_tags);
              array_push($tids, $tid_tags);
              $lang_tags = field_language('node', $node, 'field_tags');
            }
          }
          foreach ($tids as $index => $tid) { $node->field_tags[$lang_tags][$index]['tid'] = $tid; }

       }

All the credit goes to user Albright in IRC channel #drupal at http://webchat.freenode.net who pointed out to me that I needed to collect the tids in an array, then add a second loop which loops through that array and adds the tids one at a time to field_tags.