class JsOptimizer in Drupal 8

Optimizes a JavaScript asset.

Hierarchy

• class \Drupal\Core\Asset\JsOptimizer implements AssetOptimizerInterface

1 file declares its use of JsOptimizer

JsOptimizerUnitTest.php in core/tests/Drupal/Tests/Core/Asset/JsOptimizerUnitTest.php

1 string reference to 'JsOptimizer'

core.services.yml in core/core.services.yml

core/core.services.yml

1 service uses JsOptimizer

asset.js.optimizer in core/core.services.yml

Drupal\Core\Asset\JsOptimizer

File

core/lib/Drupal/Core/Asset/JsOptimizer.php, line 10

Namespace

Drupal\Core\Asset

class JsOptimizer implements AssetOptimizerInterface {

  /**
   * {@inheritdoc}
   */
  public function optimize(array $js_asset) {
    if ($js_asset['type'] !== 'file') {
      throw new \Exception('Only file JavaScript assets can be optimized.');
    }
    if (!$js_asset['preprocess']) {
      throw new \Exception('Only file JavaScript assets with preprocessing enabled can be optimized.');
    }

    // If a BOM is found, convert the file to UTF-8, then use substr() to
    // remove the BOM from the result.
    $data = file_get_contents($js_asset['data']);
    if ($encoding = Unicode::encodingFromBOM($data)) {
      $data = mb_substr(Unicode::convertToUtf8($data, $encoding), 1);
    }
    elseif (isset($js_asset['attributes']['charset'])) {
      $data = Unicode::convertToUtf8($data, $js_asset['attributes']['charset']);
    }

    // No-op optimizer: no optimizations are applied to JavaScript assets.
    return $data;
  }

  /**
   * Processes the contents of a javascript asset for cleanup.
   *
   * @param string $contents
   *   The contents of the javascript asset.
   *
   * @return string
   *   Contents of the javascript asset.
   */
  public function clean($contents) {

    // Remove JS source and source mapping urls or these may cause 404 errors.
    $contents = preg_replace('/\\/\\/(#|@)\\s(sourceURL|sourceMappingURL)=\\s*(\\S*?)\\s*$/m', '', $contents);
    return $contents;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
JsOptimizer::clean	public	function	Processes the contents of a javascript asset for cleanup. Overrides AssetOptimizerInterface::clean
JsOptimizer::optimize	public	function	Optimizes an asset. Overrides AssetOptimizerInterface::optimize