docs: def get_yaml_items(self, dir_path, param=None):
          '''
          Loops through the dir_path and parses all YAML files inside the
          directory.
  
          If no param is defined, then all YAML items will be returned
          in a list. If a param is defined, then all items will be scanned for
          this param and a list of all those values will be returned.
          '''
  
          result = []
  
          if not os.path.isdir(dir_path):
              return []
  
          for filename in os.listdir(dir_path):
  
              path  = os.path.join(dir_path, filename)
              items = self.read_yaml(path)
  
              for item in items:
                  if param:
                      if param in item:
                          item = item[param]
                          if isinstance(item, list):
                              result.extend(item)
                          else:
                              result.append(item)
                  else:
                      result.append(item)
  
          return result