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 try:
   6     input = raw_input  # pylint: disable=redefined-builtin
   7 except NameError:
   8     pass
   9
  10 logger = logging.getLogger(__name__)
  11
  12
  13 def as_string(string):
  14     """
  15     Ensure that whatever type of string is incoming, it is returned as an
  16     actual string, versus 'bytes' which Python 3 likes to use.
  17     """
  18     if isinstance(string, bytes):
  19         # we really ignore here if we can't properly decode with utf-8
  20         return string.decode('utf-8', 'ignore')
  21     return string
  22
  23
  24 def as_bytes(string):
  25     """
  26     Ensure that whatever type of string is incoming, it is returned as bytes,
  27     encoding to utf-8 otherwise
  28     """
  29     if isinstance(string, bytes):
  30         return string
  31     return string.encode('utf-8', errors='ignore')
  32
  33
  34 def str_to_int(string, round_down=True):
  35     """
  36     Parses a string number into an integer, optionally converting to a float
  37     and rounding down.
  38
  39     Some LVM values may come with a comma instead of a dot to define decimals.
  40     This function normalizes a comma into a dot
  41     """
  42     error_msg = "Unable to convert to integer: '%s'" % str(string)
  43     try:
  44         integer = float(string.replace(',', '.'))
  45     except AttributeError:
  46         # this might be a integer already, so try to use it, otherwise raise
  47         # the original exception
  48         if isinstance(string, (int, float)):
  49             integer = string
  50         else:
  51             logger.exception(error_msg)
  52             raise RuntimeError(error_msg)
  53     except (TypeError, ValueError):
  54         logger.exception(error_msg)
  55         raise RuntimeError(error_msg)
  56
  57     if round_down:
  58         integer = floor(integer)
  59     else:
  60         integer = round(integer)
  61     return int(integer)
  62
  63
  64 def str_to_bool(val):
  65     """
  66     Convert a string representation of truth to True or False
  67
  68     True values are 'y', 'yes', or ''; case-insensitive
  69     False values are 'n', or 'no'; case-insensitive
  70     Raises ValueError if 'val' is anything else.
  71     """
  72     true_vals = ['yes', 'y', '']
  73     false_vals = ['no', 'n']
  74     try:
  75         val = val.lower()
  76     except AttributeError:
  77         val = str(val).lower()
  78     if val in true_vals:
  79         return True
  80     elif val in false_vals:
  81         return False
  82     else:
  83         raise ValueError("Invalid input value: %s" % val)
  84
  85
  86 def prompt_bool(question, input_=None):
  87     """
  88     Interface to prompt a boolean (or boolean-like) response from a user.
  89     Usually a confirmation.
  90     """
  91     input_prompt = input_ or input
  92     prompt_format = '--> {question} '.format(question=question)
  93     response = input_prompt(prompt_format)
  94     try:
  95         return str_to_bool(response)
  96     except ValueError:
  97         terminal.error('Valid true responses are: y, yes, <Enter>')
  98         terminal.error('Valid false responses are: n, no')
  99         terminal.error('That response was invalid, please try again')
 100         return prompt_bool(question, input_=input_prompt)