Source Code for Module ganeti.ht

  1  # 
  2  # 
  3   
  4  # Copyright (C) 2010 Google Inc. 
  5  # 
  6  # This program is free software; you can redistribute it and/or modify 
  7  # it under the terms of the GNU General Public License as published by 
  8  # the Free Software Foundation; either version 2 of the License, or 
  9  # (at your option) any later version. 
 10  # 
 11  # This program is distributed in the hope that it will be useful, but 
 12  # WITHOUT ANY WARRANTY; without even the implied warranty of 
 13  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU 
 14  # General Public License for more details. 
 15  # 
 16  # You should have received a copy of the GNU General Public License 
 17  # along with this program; if not, write to the Free Software 
 18  # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 
 19  # 02110-1301, USA. 
 20   
 21   
 22  """Module implementing the parameter types code.""" 
 23   
 24  from ganeti import compat 
 25   
 26  # Modifiable default values; need to define these here before the 
 27  # actual LUs 
 28   
 29 -def EmptyList(): 
 30    """Returns an empty list. 
 31   
 32    """ 
 33    return [] 
 34   
 35   
 36 -def EmptyDict(): 
 37    """Returns an empty dict. 
 38   
 39    """ 
 40    return {} 
 41   
 42   
 43  #: The without-default default value 
 44  NoDefault = object() 
 45   
 46   
 47  #: The no-type (value to complex to check it in the type system) 
 48  NoType = object() 
 49   
 50   
 51  # Some basic types 
 52 -def TNotNone(val): 
 53    """Checks if the given value is not None. 
 54   
 55    """ 
 56    return val is not None 
 57   
 58   
 59 -def TNone(val): 
 60    """Checks if the given value is None. 
 61   
 62    """ 
 63    return val is None 
 64   
 65   
 66 -def TBool(val): 
 67    """Checks if the given value is a boolean. 
 68   
 69    """ 
 70    return isinstance(val, bool) 
 71   
 72   
 73 -def TInt(val): 
 74    """Checks if the given value is an integer. 
 75   
 76    """ 
 77    # For backwards compatibility with older Python versions, boolean values are 
 78    # also integers and should be excluded in this test. 
 79    # 
 80    # >>> (isinstance(False, int), isinstance(True, int)) 
 81    # (True, True) 
 82    return isinstance(val, int) and not isinstance(val, bool) 
 83   
 84   
 85 -def TFloat(val): 
 86    """Checks if the given value is a float. 
 87   
 88    """ 
 89    return isinstance(val, float) 
 90   
 91   
 92 -def TString(val): 
 93    """Checks if the given value is a string. 
 94   
 95    """ 
 96    return isinstance(val, basestring) 
 97   
 98   
 99 -def TTrue(val): 
100    """Checks if a given value evaluates to a boolean True value. 
101   
102    """ 
103    return bool(val) 
104   
105   
106 -def TElemOf(target_list): 
107    """Builds a function that checks if a given value is a member of a list. 
108   
109    """ 
110    return lambda val: val in target_list 
111   
112   
113  # Container types 
114 -def TList(val): 
115    """Checks if the given value is a list. 
116   
117    """ 
118    return isinstance(val, list) 
119   
120   
121 -def TDict(val): 
122    """Checks if the given value is a dictionary. 
123   
124    """ 
125    return isinstance(val, dict) 
126   
127   
128 -def TIsLength(size): 
129    """Check is the given container is of the given size. 
130   
131    """ 
132    return lambda container: len(container) == size 
133   
134   
135  # Combinator types 
136 -def TAnd(*args): 
137    """Combine multiple functions using an AND operation. 
138   
139    """ 
140    def fn(val): 
141      return compat.all(t(val) for t in args) 
142    return fn 
143   
144   
145 -def TOr(*args): 
146    """Combine multiple functions using an AND operation. 
147   
148    """ 
149    def fn(val): 
150      return compat.any(t(val) for t in args) 
151    return fn 
152   
153   
154 -def TMap(fn, test): 
155    """Checks that a modified version of the argument passes the given test. 
156   
157    """ 
158    return lambda val: test(fn(val)) 
159   
160   
161  # Type aliases 
162   
163  #: a non-empty string 
164  TNonEmptyString = TAnd(TString, TTrue) 
165   
166  #: a maybe non-empty string 
167  TMaybeString = TOr(TNonEmptyString, TNone) 
168   
169  #: a maybe boolean (bool or none) 
170  TMaybeBool = TOr(TBool, TNone) 
171   
172  #: Maybe a dictionary (dict or None) 
173  TMaybeDict = TOr(TDict, TNone) 
174   
175  #: a positive integer 
176  TPositiveInt = TAnd(TInt, lambda v: v >= 0) 
177   
178  #: a strictly positive integer 
179  TStrictPositiveInt = TAnd(TInt, lambda v: v > 0) 
180   
181  #: Number 
182  TNumber = TOr(TInt, TFloat) 
183   
184   
185 -def TListOf(my_type): 
186    """Checks if a given value is a list with all elements of the same type. 
187   
188    """ 
189    return TAnd(TList, 
190                 lambda lst: compat.all(my_type(v) for v in lst)) 
191   
192   
193 -def TDictOf(key_type, val_type): 
194    """Checks a dict type for the type of its key/values. 
195   
196    """ 
197    return TAnd(TDict, 
198                lambda my_dict: (compat.all(key_type(v) for v in my_dict.keys()) 
199                                 and compat.all(val_type(v) 
200                                                for v in my_dict.values()))) 
201