refactored removed functions from d8 api

node_authlink.module

 <?php
 // $Id$
+use Drupal\Component\Utility\Crypt;
 use Drupal\Core\Access\AccessResult;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Session\AccountInterface;
@@ -45,7 +46,9 @@ function node_authlink_form_node_type_form_alter(&$form, FormStateInterface &$fo
   ];
 
   // Time periods:                 none, 1 day, 1 week, 4 weeks
-  $period = drupal_map_assoc([0, 86400, 604800, 2419200], 'format_interval');
+  $time_periods = [0, 86400, 604800, 2419200];
+  $period = array_map('format_interval', array_combine($time_periods, $time_periods));
+
   $period[0] = '<' . t('disabled') . '>';
   $form['node_authlink']['node_authlink_expire'] = [
     '#type' => 'select',
@@ -241,14 +244,15 @@ function node_authlink_node_access(NodeInterface $node, $op, AccountInterface $a
  *
  * Pre-generate auth key for the new node (e.g. for use in Rules).
  */
-function node_authlink_node_presave($node) {
+function node_authlink_node_presave(Node $node) {
   // Ignore if node type is disabled
-  if (!variable_get('node_authlink_enable_' . $node->type, FALSE)) {
+  $config = \Drupal::config('node_authlink.settings');
+  if (!$config->get('enable.' . $node->bundle())) {
     return;
   }
 
   // Generate key
-  $node->authkey = hash('sha256', drupal_random_bytes(64));
+  $node->authkey = hash('sha256', Crypt::randomBytes(64));
 }
 
 /**
@@ -262,16 +266,17 @@ function node_authlink_node_insert($node) {
     $nid = $node;
   }
   else {
-    $nid = $node->nid;
+    $nid = $node->id();
 
+    $config = \Drupal::config('node_authlink.settings');
     // Ignore if node type is disabled
-    if (!variable_get('node_authlink_enable_' . $node->type, FALSE)) {
+    if (!$config->get('enable.' . $node->bundle())) {
       return;
     }
   }
 
   // Generate key if not yet
-  $authkey = isset($node->authkey) ? $node->authkey : hash('sha256', drupal_random_bytes(64));
+  $authkey = isset($node->authkey) ? $node->authkey : hash('sha256', Crypt::randomBytes(64));
 
   // Save to DB
   db_insert('node_authlink_nodes')
@@ -288,9 +293,10 @@ function node_authlink_node_insert($node) {
  */
 function node_authlink_cron() {
   $node_types = node_type_get_types();
+  $config = \Drupal::config('node_authlink.settings');
 
   foreach ($node_types as $type) {
-    $expire = variable_get('node_authlink_expire_' . $type->type, 0);
+    $expire = $config->get('expire.' . $type->id());
     if (!$expire) {
       continue;
     }
@@ -299,7 +305,7 @@ function node_authlink_cron() {
     $query = db_select('node', 'n');
     $query->leftJoin('node_authlink_nodes', 'a', 'n.nid = a.nid');
     $query->fields('n', ['nid'])
-      ->condition('n.type', $type->type)
+      ->condition('n.type', $type->id())
       ->condition('a.created', time() - $expire, '<');
     $nids = $query->execute()->fetchCol();