protected function Container::dataLayerSnippet in GoogleTagManager 8

Returns JavaScript data layer snippet or adds items to data layer.

Return value

string|null The data layer snippet or NULL.

1 call to Container::dataLayerSnippet()

Container::snippets in src/Entity/Container.php

Returns array of JavaScript snippets.

File

src/Entity/Container.php, line 304

Class

Container

Defines the container configuration entity.

Namespace

Drupal\google_tag\Entity

Code

protected function dataLayerSnippet() {

  // Gather data.
  $data_layer = $this
    ->variableClean('data_layer');
  $whitelist = $this
    ->get('whitelist_classes');
  $blacklist = $this
    ->get('blacklist_classes');
  $classes = [];
  $names = [
    'whitelist',
    'blacklist',
  ];
  foreach ($names as $name) {
    if (empty(${$name})) {
      continue;
    }

    // @see https://www.drupal.org/files/issues/add_options_to-2851405-7.patch
    // this suggests to flip order of previous two statements; yet if user
    // enters a new line in textarea, then this change does not eliminate the
    // empty script item. Need to trim "\n" from ends of string.
    ${$name} = explode("\n", ${$name});
    $classes["gtm.{$name}"] = ${$name};
  }
  if ($classes) {

    // Build data layer snippet.
    $classes = json_encode($classes);
    $script = <<<EOS
(function(w,l){
  w[l]=w[l]||[];
  w[l].push({<span class="php-variable">$classes</span>});
})(window,'{<span class="php-variable">$data_layer</span>}');
EOS;
    return $this
      ->compactSnippet($script);
  }
}