HeadersCacheContext::getContext

public HeadersCacheContext::getContext($header = NULL)

Returns the string representation of the cache context.

A cache context service's name is used as a token (placeholder) cache key, and is then replaced with the string returned by this method.

Parameters

string|null $parameter: The parameter, or NULL to indicate all possible parameter values.

Return value

string The string representation of the cache context. When $parameter is NULL, a value representing all possible parameters must be generated.

Throws

\LogicException Thrown if the passed in parameter is invalid.

Overrides CalculatedCacheContextInterface::getContext

File

core/lib/Drupal/Core/Cache/Context/HeadersCacheContext.php, line 26

Class

HeadersCacheContext

Defines the HeadersCacheContext service, for "per header" caching.

Namespace

Drupal\Core\Cache\Context

Code

public function getContext($header = NULL) {
  if ($header === NULL) {
    return $this->requestStack->getCurrentRequest()->headers->all();
  }
  else {
    return $this->requestStack->getCurrentRequest()->headers->get($header);
  }
}