filters.py 文件源码

def extract_by_prefix(values, prefix):
    """
    This function takes a list as 'values' parameter and extract a first value from the list which contains prefix.
    The prefix is defined in parameter 'prefix'
    """
    if values is None:
      raise errors.AnsibleFilterError('Values is not provided')

    if prefix is None:
      raise errors.AnsibleFilterError('Prefix is not provided')

    if not isinstance(values, list):
      raise errors.AnsibleFilterError('Wrong type for values')

    if not isinstance(prefix, str):
      raise errors.AnsibleFilterError('Wrong type for the prefix')

    if len(values) == 0:
       raise errors.AnsibleFilterError('Empty list. Nothing to extract')

    for v in values:
      if v.startswith(prefix):
        return v

    raise errors.AnsibleFilterError('Value not found')