Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/absl_py-2.0.0-py3.8.egg/absl/flags/_validators_classes.py: 44%

1# Copyright 2021 The Abseil Authors. 

2# 

3# Licensed under the Apache License, Version 2.0 (the "License"); 

4# you may not use this file except in compliance with the License. 

5# You may obtain a copy of the License at 

6# 

7# http://www.apache.org/licenses/LICENSE-2.0 

8# 

9# Unless required by applicable law or agreed to in writing, software 

10# distributed under the License is distributed on an "AS IS" BASIS, 

11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 

12# See the License for the specific language governing permissions and 

13# limitations under the License. 

14 

15"""Defines *private* classes used for flag validators. 

16 

17Do NOT import this module. DO NOT use anything from this module. They are 

18private APIs. 

19""" 

20 

21from absl.flags import _exceptions 

22 

23 

24class Validator(object): 

25 """Base class for flags validators. 

26 

27 Users should NOT overload these classes, and use flags.Register... 

28 methods instead. 

29 """ 

30 

31 # Used to assign each validator an unique insertion_index 

32 validators_count = 0 

33 

34 def __init__(self, checker, message): 

35 """Constructor to create all validators. 

36 

37 Args: 

38 checker: function to verify the constraint. 

39 Input of this method varies, see SingleFlagValidator and 

40 multi_flags_validator for a detailed description. 

41 message: str, error message to be shown to the user. 

42 """ 

43 self.checker = checker 

44 self.message = message 

45 Validator.validators_count += 1 

46 # Used to assert validators in the order they were registered. 

47 self.insertion_index = Validator.validators_count 

48 

49 def verify(self, flag_values): 

50 """Verifies that constraint is satisfied. 

51 

52 flags library calls this method to verify Validator's constraint. 

53 

54 Args: 

55 flag_values: flags.FlagValues, the FlagValues instance to get flags from. 

56 Raises: 

57 Error: Raised if constraint is not satisfied. 

58 """ 

59 param = self._get_input_to_checker_function(flag_values) 

60 if not self.checker(param): 

61 raise _exceptions.ValidationError(self.message) 

62 

63 def get_flags_names(self): 

64 """Returns the names of the flags checked by this validator. 

65 

66 Returns: 

67 [string], names of the flags. 

68 """ 

69 raise NotImplementedError('This method should be overloaded') 

70 

71 def print_flags_with_values(self, flag_values): 

72 raise NotImplementedError('This method should be overloaded') 

73 

74 def _get_input_to_checker_function(self, flag_values): 

75 """Given flag values, returns the input to be given to checker. 

76 

77 Args: 

78 flag_values: flags.FlagValues, containing all flags. 

79 Returns: 

80 The input to be given to checker. The return type depends on the specific 

81 validator. 

82 """ 

83 raise NotImplementedError('This method should be overloaded') 

84 

85 

86class SingleFlagValidator(Validator): 

87 """Validator behind register_validator() method. 

88 

89 Validates that a single flag passes its checker function. The checker function 

90 takes the flag value and returns True (if value looks fine) or, if flag value 

91 is not valid, either returns False or raises an Exception. 

92 """ 

93 

94 def __init__(self, flag_name, checker, message): 

95 """Constructor. 

96 

97 Args: 

98 flag_name: string, name of the flag. 

99 checker: function to verify the validator. 

100 input - value of the corresponding flag (string, boolean, etc). 

101 output - bool, True if validator constraint is satisfied. 

102 If constraint is not satisfied, it should either return False or 

103 raise flags.ValidationError(desired_error_message). 

104 message: str, error message to be shown to the user if validator's 

105 condition is not satisfied. 

106 """ 

107 super(SingleFlagValidator, self).__init__(checker, message) 

108 self.flag_name = flag_name 

109 

110 def get_flags_names(self): 

111 return [self.flag_name] 

112 

113 def print_flags_with_values(self, flag_values): 

114 return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) 

115 

116 def _get_input_to_checker_function(self, flag_values): 

117 """Given flag values, returns the input to be given to checker. 

118 

119 Args: 

120 flag_values: flags.FlagValues, the FlagValues instance to get flags from. 

121 Returns: 

122 object, the input to be given to checker. 

123 """ 

124 return flag_values[self.flag_name].value 

125 

126 

127class MultiFlagsValidator(Validator): 

128 """Validator behind register_multi_flags_validator method. 

129 

130 Validates that flag values pass their common checker function. The checker 

131 function takes flag values and returns True (if values look fine) or, 

132 if values are not valid, either returns False or raises an Exception. 

133 """ 

134 

135 def __init__(self, flag_names, checker, message): 

136 """Constructor. 

137 

138 Args: 

139 flag_names: [str], containing names of the flags used by checker. 

140 checker: function to verify the validator. 

141 input - dict, with keys() being flag_names, and value for each 

142 key being the value of the corresponding flag (string, boolean, 

143 etc). 

144 output - bool, True if validator constraint is satisfied. 

145 If constraint is not satisfied, it should either return False or 

146 raise flags.ValidationError(desired_error_message). 

147 message: str, error message to be shown to the user if validator's 

148 condition is not satisfied 

149 """ 

150 super(MultiFlagsValidator, self).__init__(checker, message) 

151 self.flag_names = flag_names 

152 

153 def _get_input_to_checker_function(self, flag_values): 

154 """Given flag values, returns the input to be given to checker. 

155 

156 Args: 

157 flag_values: flags.FlagValues, the FlagValues instance to get flags from. 

158 Returns: 

159 dict, with keys() being self.flag_names, and value for each key 

160 being the value of the corresponding flag (string, boolean, etc). 

161 """ 

162 return dict([key, flag_values[key].value] for key in self.flag_names) 

163 

164 def print_flags_with_values(self, flag_values): 

165 prefix = 'flags ' 

166 flags_with_values = [] 

167 for key in self.flag_names: 

168 flags_with_values.append('%s=%s' % (key, flag_values[key].value)) 

169 return prefix + ', '.join(flags_with_values) 

170 

171 def get_flags_names(self): 

172 return self.flag_names