1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
# This file is part of MyPaint.
# Copyright (C) 2020 by the MyPaint Development Team
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
from __future__ import division, print_function
import logging
logger = logging.getLogger(__name__)
def validate(input_value, default_value, input_type, predicate, error_message):
""" Validate user input, returning a default value on failed validations
:param input_value: The value to validate
:param default_value: The default value to return if validation fails
:param input_type: Type or constructor taking the input value
:param predicate: A unary truth-value function which is run against the
output of the type / constructor applied to the input value.
:param error_message: Error message to log on validation failure. The
message may contain "{value}" to refer to the input value.
:return: The converted input value if validation is successful, otherwise
the given default value.
"""
try:
value = input_type(input_value)
assert predicate(value)
return value
except Exception:
logger.exception()
logger.error(error_message.format(value=input_value))
return default_value
|
