ceph/src/ceph-volume/ceph_volume/util/__init__.py

   1 import logging
   2 from math import floor
   3 from ceph_volume import terminal
   4
   5
   6 logger = logging.getLogger(__name__)
   7
   8
   9 def as_string(string):
  10     """
  11     Ensure that whatever type of string is incoming, it is returned as an
  12     actual string, versus 'bytes' which Python 3 likes to use.
  13     """
  14     if isinstance(string, bytes):
  15         # we really ignore here if we can't properly decode with utf-8
  16         return string.decode('utf-8', 'ignore')
  17     return string
  18
  19
  20 def as_bytes(string):
  21     """
  22     Ensure that whatever type of string is incoming, it is returned as bytes,
  23     encoding to utf-8 otherwise
  24     """
  25     if isinstance(string, bytes):
  26         return string
  27     return string.encode('utf-8', errors='ignore')
  28
  29
  30 def str_to_int(string, round_down=True):
  31     """
  32     Parses a string number into an integer, optionally converting to a float
  33     and rounding down.
  34     """
  35     error_msg = "Unable to convert to integer: '%s'" % str(string)
  36     try:
  37         integer = float(string)
  38     except (TypeError, ValueError):
  39         logger.exception(error_msg)
  40         raise RuntimeError(error_msg)
  41
  42     if round_down:
  43         integer = floor(integer)
  44     else:
  45         integer = round(integer)
  46     return int(integer)
  47
  48
  49 def str_to_bool(val):
  50     """
  51     Convert a string representation of truth to True or False
  52
  53     True values are 'y', 'yes', or ''; case-insensitive
  54     False values are 'n', or 'no'; case-insensitive
  55     Raises ValueError if 'val' is anything else.
  56     """
  57     true_vals = ['yes', 'y', '']
  58     false_vals = ['no', 'n']
  59     try:
  60         val = val.lower()
  61     except AttributeError:
  62         val = str(val).lower()
  63     if val in true_vals:
  64         return True
  65     elif val in false_vals:
  66         return False
  67     else:
  68         raise ValueError("Invalid input value: %s" % val)
  69
  70
  71 def prompt_bool(question, _raw_input=None):
  72     """
  73     Interface to prompt a boolean (or boolean-like) response from a user.
  74     Usually a confirmation.
  75     """
  76     input_prompt = _raw_input or raw_input
  77     prompt_format = '--> {question} '.format(question=question)
  78     response = input_prompt(prompt_format)
  79     try:
  80         return str_to_bool(response)
  81     except ValueError:
  82         terminal.error('Valid true responses are: y, yes, <Enter>')
  83         terminal.error('Valid false responses are: n, no')
  84         terminal.error('That response was invalid, please try again')
  85         return prompt_bool(question, _raw_input=input_prompt)