How do I render a block programmatically with the standard template?

Question

I'm using the following code to render a set of blocks programmatically:

$region_content = [];
$block_manager = \Drupal::service('plugin.manager.block');
$blocks = $this->getBlocks();
foreach ($blocks[$region_name] as $key=>$block_config) {
  $instance = $block_manager->createInstance($block_config['plugin_id'], $block_config['config']);
  $region_content[] = [
    $instance->build();
  ];
}

The contents of $block_config['config'] look like this:

[
  'provider' => 'search',
  'admin_label' => '',
  'label' => 'Search form',
  'label_display' => TRUE,
  'third_party_settings' => [
    'block_aria_landmark_roles' => [
      'role' => '',
    ],
  ],
]

The resulting $instance object seems to work correctly, and when I render $region_content I do indeed get the contents of the blocks as expected. But they are not wrapped in the block template. I thought I might have to do something like this:

$region_content[] = [
  '#theme' => 'block',
  'contents' => $instance->build(),
];

...but that doesn't work at all. How do I take this $instance object and render it using the standard block template? Or am I completely off course here?

Answer 1

Yes, you need a render element with #theme = block, but this looks more like this example:

$build = [
  '#theme' => 'block',
  '#attributes' => [],
  '#contextual_links' => [
    'block' => [
      'route_parameters' => ['block' => $entity->id()],
    ],
  ],
  '#weight' => $entity->getWeight(),
  '#configuration' => $configuration,
  '#plugin_id' => $plugin_id,
  '#base_plugin_id' => $base_id,
  '#derivative_plugin_id' => $derivative_id,
  '#id' => $entity->id(),
  '#pre_render' => [
    static::class . '::preRender',
  ],
  '#block' => $entity,
];

You don't need to build this yourself, better use the view builder (where this code is from):

$build = \Drupal::entityTypeManager()->getViewBuilder('block')->view($block);

Where $block is the entity of the configured block:

$block = \Drupal::entityTypeManager()->getStorage('block')->load($block_id);

To get all configured blocks of a region see How to get block layout programmatically?

Answer 2

If you want to render blocks directly from twig you can use:

Twig tweak 8.x-1.9 https://www.drupal.org/project/twig_tweak

You just need to install it. The block should be configured on "admin/structure/block" page. Example how to use: <dt>Block:</dt> <dd>{{ drupal_block('system_powered_by_block') }}</dd>

Add this code directly in the twig template file.