Entity Export

export.php

<?php

$data = \Drupal\Component\Serialization\Yaml::decode(file_get_contents('node.yml'));

$entity_type = \Drupal::entityManager()->getDefinition('node');

if ($entity_type->hasKey('bundle')) {
  $data[$entity_type->getKey('bundle')] = $data[$entity_type->getKey('bundle')][0]['target_id'];
}

$entity = NULL;

if ($entity_type->hasKey('uuid')) {
  if (!empty($data[$entity_type->getKey('uuid')][0]['value'])) {
    $entity = entity_load_by_uuid('node', $data['uuid'][0]['value']);
  }
}

if ($entity) {

  foreach ($entity->getFields() as $name => $property) {

    if (isset($data[$name])) {
      $property->setValue($data[$name]);
    }

  }

  if ($entity_type->isRevisionable()) {
    $entity->setNewRevision();
  }

}
else {
  $entity = entity_create('node', $data);
}


$entity->save();

import.php

<?php

$node = \Drupal\node\Entity\Node::load(4);

$data = $node->toArray();

if ($node->getEntityType()->hasKey('id')) {
  unset($data[$node->getEntityType()->getKey('id')]);
}

if ($node->getEntityType()->hasKey('revision')) {
  unset($data[$node->getEntityType()->getKey('revision')]);
}

$yaml = \Drupal\Component\Serialization\Yaml::encode($data);

file_put_contents('node.yml', $yaml);