Say a site has a very deep taxonomy structure, and a user wants to create a number of nodes in the same category. This can be rather frustrating for them to have to scroll through and select the correct taxonomy for each node added.

This mini-module was based on the taxonomy_defaults.module but saves taxonomy submitted in a session variable for re-use rather than overriding all node creations with admin configured values. Of course, as a result you might get unwanted conflicts between the two (check their weights).

I called this taxonomy_session_defaults.module, but anything suitable will do.

1. Create a directory under modules named taxonomy_session_defaults.

2. Put the following in taxonomy_session_defaults.module:

<?php

/**
 * Adds the last saved session values for active vocabularies as preselected terms to '$node->taxonomy'
 * This requires a weight lower than taxonomy.module.
 *
 * This may well conflict with taxonomy_defaults.module, you may want to tweak the weights of these.
 */
function taxonomy_session_defaults_form_alter($form_id, &$form) {
  // Only alter node forms
  if (isset($form['type']) && $form['type']['#value'] .'_node_form' == $form_id) {
    $node = $form['#node'];
    // Do not override terms on nodes that already have been edited
    if (!isset($node->nid)) {
      // Add the default session terms to this form
      foreach (taxonomy_get_vocabularies($node->type) as $vid => $vocab) {
        if ($_SESSION["taxses_{$node->type}_{$vid}"]) {
          $session_tids = split(",", $_SESSION["taxses_{$node->type}_{$vid}"]);
          foreach ($session_tids as $tid) {
            $term = taxonomy_get_term($tid);
            $form['#node']->taxonomy[$tid] = $term;
          }
        }
      }
    }
  }
}

/**
 * Saves the selected taxonomy so it's used again in the next node created.
 */
function taxonomy_session_defaults_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
  if ($op == 'submit') {
    $taxonomy = $node->taxonomy;

    foreach ($taxonomy as $vid => $terms) {
      if (is_array($terms)) {
        // Save the array of terms
        $_SESSION["taxses_{$node->type}_{$vid}"] = join(",", $terms);
      } else if ($terms != 0) {
        // Save a single term
        $_SESSION["taxses_{$node->type}_{$vid}"] = $terms;
      } else {
        // Remove anything previously saved
        unset($_SESSION["taxses_{$node->type}_{$vid}"]);
      }
    }
  }
}

?>

3. Put the following in taxonomy_session_defaults.info:

name = Taxonomy Session Defaults
description = Assign default taxonomy terms per node-type based on last saved node.
dependencies = taxonomy
version = "5.x-0.1"

4. Put the following in taxonomy_session_defaults.install:

<?php

/**
 * Hook sets taxonomy_session_defaults 'weight' to -2.
 * This ensures that it's hook_form_alter runs before taxonomy & taxonomy_defaults.
 * Admins may wish to tweak this weight.
 *
 */
function taxonomy_session_defaults_install() {
  $ret = array();
  $ret[] = db_query("UPDATE {system} SET weight = -2 WHERE name = 'taxonomy_session_defaults'");
  return $ret;
}

?>

5. Visit modules admin page and enable the new module.