class WorkspaceCacheContext

class WorkspaceCacheContext implements CacheContextInterface {
    
    /**
     * The workspace manager.
     *
     * @var \Drupal\workspaces\WorkspaceManagerInterface
     */
    protected $workspaceManager;
    
    /**
     * Constructs a new WorkspaceCacheContext service.
     *
     * @param \Drupal\workspaces\WorkspaceManagerInterface $workspace_manager
     *   The workspace manager.
     */
    public function __construct(WorkspaceManagerInterface $workspace_manager) {
        $this->workspaceManager = $workspace_manager;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getLabel() {
        return t('Workspace');
    }
    
    /**
     * {@inheritdoc}
     */
    public function getContext() {
        return $this->workspaceManager
            ->hasActiveWorkspace() ? $this->workspaceManager
            ->getActiveWorkspace()
            ->id() : 'live';
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCacheableMetadata($type = NULL) {
        // The active workspace will always be stored in the user's session.
        $cacheability = new CacheableMetadata();
        $cacheability->addCacheContexts([
            'session',
        ]);
        return $cacheability;
    }

}