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1# This file is part of pex_config. 

2# 

3# Developed for the LSST Data Management System. 

4# This product includes software developed by the LSST Project 

5# (http://www.lsst.org). 

6# See the COPYRIGHT file at the top-level directory of this distribution 

7# for details of code ownership. 

8# 

9# This software is dual licensed under the GNU General Public License and also 

10# under a 3-clause BSD license. Recipients may choose which of these licenses 

11# to use; please see the files gpl-3.0.txt and/or bsd_license.txt, 

12# respectively. If you choose the GPL option then the following text applies 

13# (but note that there is still no warranty even if you opt for BSD instead): 

14# 

15# This program is free software: you can redistribute it and/or modify 

16# it under the terms of the GNU General Public License as published by 

17# the Free Software Foundation, either version 3 of the License, or 

18# (at your option) any later version. 

19# 

20# This program is distributed in the hope that it will be useful, 

21# but WITHOUT ANY WARRANTY; without even the implied warranty of 

22# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 

23# GNU General Public License for more details. 

24# 

25# You should have received a copy of the GNU General Public License 

26# along with this program. If not, see <http://www.gnu.org/licenses/>. 

27 

28__all__ = ["DictField"] 

29 

30import collections.abc 

31 

32from .config import Field, FieldValidationError, _typeStr, _autocast, _joinNamePath 

33from .comparison import getComparisonName, compareScalars 

34from .callStack import getCallStack, getStackFrame 

35 

36 

37class Dict(collections.abc.MutableMapping): 

38 """An internal mapping container. 

39 

40 This class emulates a `dict`, but adds validation and provenance. 

41 """ 

42 

43 def __init__(self, config, field, value, at, label, setHistory=True): 

44 self._field = field 

45 self._config = config 

46 self._dict = {} 

47 self._history = self._config._history.setdefault(self._field.name, []) 

48 self.__doc__ = field.doc 

49 if value is not None: 

50 try: 

51 for k in value: 

52 # do not set history per-item 

53 self.__setitem__(k, value[k], at=at, label=label, setHistory=False) 

54 except TypeError: 

55 msg = "Value %s is of incorrect type %s. Mapping type expected." % \ 

56 (value, _typeStr(value)) 

57 raise FieldValidationError(self._field, self._config, msg) 

58 if setHistory: 

59 self._history.append((dict(self._dict), at, label)) 

60 

61 history = property(lambda x: x._history) 61 ↛ exitline 61 didn't run the lambda on line 61

62 """History (read-only). 

63 """ 

64 

65 def __getitem__(self, k): 

66 return self._dict[k] 

67 

68 def __len__(self): 

69 return len(self._dict) 

70 

71 def __iter__(self): 

72 return iter(self._dict) 

73 

74 def __contains__(self, k): 

75 return k in self._dict 

76 

77 def __setitem__(self, k, x, at=None, label="setitem", setHistory=True): 

78 if self._config._frozen: 

79 msg = "Cannot modify a frozen Config. "\ 

80 "Attempting to set item at key %r to value %s" % (k, x) 

81 raise FieldValidationError(self._field, self._config, msg) 

82 

83 # validate keytype 

84 k = _autocast(k, self._field.keytype) 

85 if type(k) != self._field.keytype: 

86 msg = "Key %r is of type %s, expected type %s" % \ 

87 (k, _typeStr(k), _typeStr(self._field.keytype)) 

88 raise FieldValidationError(self._field, self._config, msg) 

89 

90 # validate itemtype 

91 x = _autocast(x, self._field.itemtype) 

92 if self._field.itemtype is None: 

93 if type(x) not in self._field.supportedTypes and x is not None: 

94 msg = "Value %s at key %r is of invalid type %s" % (x, k, _typeStr(x)) 

95 raise FieldValidationError(self._field, self._config, msg) 

96 else: 

97 if type(x) != self._field.itemtype and x is not None: 

98 msg = "Value %s at key %r is of incorrect type %s. Expected type %s" % \ 

99 (x, k, _typeStr(x), _typeStr(self._field.itemtype)) 

100 raise FieldValidationError(self._field, self._config, msg) 

101 

102 # validate item using itemcheck 

103 if self._field.itemCheck is not None and not self._field.itemCheck(x): 

104 msg = "Item at key %r is not a valid value: %s" % (k, x) 

105 raise FieldValidationError(self._field, self._config, msg) 

106 

107 if at is None: 

108 at = getCallStack() 

109 

110 self._dict[k] = x 

111 if setHistory: 

112 self._history.append((dict(self._dict), at, label)) 

113 

114 def __delitem__(self, k, at=None, label="delitem", setHistory=True): 

115 if self._config._frozen: 

116 raise FieldValidationError(self._field, self._config, 

117 "Cannot modify a frozen Config") 

118 

119 del self._dict[k] 

120 if setHistory: 

121 if at is None: 

122 at = getCallStack() 

123 self._history.append((dict(self._dict), at, label)) 

124 

125 def __repr__(self): 

126 return repr(self._dict) 

127 

128 def __str__(self): 

129 return str(self._dict) 

130 

131 def __setattr__(self, attr, value, at=None, label="assignment"): 

132 if hasattr(getattr(self.__class__, attr, None), '__set__'): 

133 # This allows properties to work. 

134 object.__setattr__(self, attr, value) 

135 elif attr in self.__dict__ or attr in ["_field", "_config", "_history", "_dict", "__doc__"]: 

136 # This allows specific private attributes to work. 

137 object.__setattr__(self, attr, value) 

138 else: 

139 # We throw everything else. 

140 msg = "%s has no attribute %s" % (_typeStr(self._field), attr) 

141 raise FieldValidationError(self._field, self._config, msg) 

142 

143 

144class DictField(Field): 

145 """A configuration field (`~lsst.pex.config.Field` subclass) that maps keys 

146 and values. 

147 

148 The types of both items and keys are restricted to these builtin types: 

149 `int`, `float`, `complex`, `bool`, and `str`). All keys share the same type 

150 and all values share the same type. Keys can have a different type from 

151 values. 

152 

153 Parameters 

154 ---------- 

155 doc : `str` 

156 A documentation string that describes the configuration field. 

157 keytype : {`int`, `float`, `complex`, `bool`, `str`} 

158 The type of the mapping keys. All keys must have this type. 

159 itemtype : {`int`, `float`, `complex`, `bool`, `str`} 

160 Type of the mapping values. 

161 default : `dict`, optional 

162 The default mapping. 

163 optional : `bool`, optional 

164 If `True`, the field doesn't need to have a set value. 

165 dictCheck : callable 

166 A function that validates the dictionary as a whole. 

167 itemCheck : callable 

168 A function that validates individual mapping values. 

169 deprecated : None or `str`, optional 

170 A description of why this Field is deprecated, including removal date. 

171 If not None, the string is appended to the docstring for this Field. 

172 

173 See also 

174 -------- 

175 ChoiceField 

176 ConfigChoiceField 

177 ConfigDictField 

178 ConfigField 

179 ConfigurableField 

180 Field 

181 ListField 

182 RangeField 

183 RegistryField 

184 

185 Examples 

186 -------- 

187 This field maps has `str` keys and `int` values: 

188 

189 >>> from lsst.pex.config import Config, DictField 

190 >>> class MyConfig(Config): 

191 ... field = DictField( 

192 ... doc="Example string-to-int mapping field.", 

193 ... keytype=str, itemtype=int, 

194 ... default={}) 

195 ... 

196 >>> config = MyConfig() 

197 >>> config.field['myKey'] = 42 

198 >>> print(config.field) 

199 {'myKey': 42} 

200 """ 

201 

202 DictClass = Dict 

203 

204 def __init__(self, doc, keytype, itemtype, default=None, optional=False, dictCheck=None, itemCheck=None, 

205 deprecated=None): 

206 source = getStackFrame() 

207 self._setup(doc=doc, dtype=Dict, default=default, check=None, 

208 optional=optional, source=source, deprecated=deprecated) 

209 if keytype not in self.supportedTypes: 209 ↛ 210line 209 didn't jump to line 210, because the condition on line 209 was never true

210 raise ValueError("'keytype' %s is not a supported type" % 

211 _typeStr(keytype)) 

212 elif itemtype is not None and itemtype not in self.supportedTypes: 212 ↛ 213line 212 didn't jump to line 213, because the condition on line 212 was never true

213 raise ValueError("'itemtype' %s is not a supported type" % 

214 _typeStr(itemtype)) 

215 if dictCheck is not None and not hasattr(dictCheck, "__call__"): 215 ↛ 216line 215 didn't jump to line 216, because the condition on line 215 was never true

216 raise ValueError("'dictCheck' must be callable") 

217 if itemCheck is not None and not hasattr(itemCheck, "__call__"): 217 ↛ 218line 217 didn't jump to line 218, because the condition on line 217 was never true

218 raise ValueError("'itemCheck' must be callable") 

219 

220 self.keytype = keytype 

221 self.itemtype = itemtype 

222 self.dictCheck = dictCheck 

223 self.itemCheck = itemCheck 

224 

225 def validate(self, instance): 

226 """Validate the field's value (for internal use only). 

227 

228 Parameters 

229 ---------- 

230 instance : `lsst.pex.config.Config` 

231 The configuration that contains this field. 

232 

233 Returns 

234 ------- 

235 isValid : `bool` 

236 `True` is returned if the field passes validation criteria (see 

237 *Notes*). Otherwise `False`. 

238 

239 Notes 

240 ----- 

241 This method validates values according to the following criteria: 

242 

243 - A non-optional field is not `None`. 

244 - If a value is not `None`, is must pass the `ConfigField.dictCheck` 

245 user callback functon. 

246 

247 Individual item checks by the `ConfigField.itemCheck` user callback 

248 function are done immediately when the value is set on a key. Those 

249 checks are not repeated by this method. 

250 """ 

251 Field.validate(self, instance) 

252 value = self.__get__(instance) 

253 if value is not None and self.dictCheck is not None \ 

254 and not self.dictCheck(value): 

255 msg = "%s is not a valid value" % str(value) 

256 raise FieldValidationError(self, instance, msg) 

257 

258 def __set__(self, instance, value, at=None, label="assignment"): 

259 if instance._frozen: 

260 msg = "Cannot modify a frozen Config. "\ 

261 "Attempting to set field to value %s" % value 

262 raise FieldValidationError(self, instance, msg) 

263 

264 if at is None: 

265 at = getCallStack() 

266 if value is not None: 

267 value = self.DictClass(instance, self, value, at=at, label=label) 

268 else: 

269 history = instance._history.setdefault(self.name, []) 

270 history.append((value, at, label)) 

271 

272 instance._storage[self.name] = value 

273 

274 def toDict(self, instance): 

275 """Convert this field's key-value pairs into a regular `dict`. 

276 

277 Parameters 

278 ---------- 

279 instance : `lsst.pex.config.Config` 

280 The configuration that contains this field. 

281 

282 Returns 

283 ------- 

284 result : `dict` or `None` 

285 If this field has a value of `None`, then this method returns 

286 `None`. Otherwise, this method returns the field's value as a 

287 regular Python `dict`. 

288 """ 

289 value = self.__get__(instance) 

290 return dict(value) if value is not None else None 

291 

292 def _compare(self, instance1, instance2, shortcut, rtol, atol, output): 

293 """Compare two fields for equality. 

294 

295 Used by `lsst.pex.ConfigDictField.compare`. 

296 

297 Parameters 

298 ---------- 

299 instance1 : `lsst.pex.config.Config` 

300 Left-hand side config instance to compare. 

301 instance2 : `lsst.pex.config.Config` 

302 Right-hand side config instance to compare. 

303 shortcut : `bool` 

304 If `True`, this function returns as soon as an inequality if found. 

305 rtol : `float` 

306 Relative tolerance for floating point comparisons. 

307 atol : `float` 

308 Absolute tolerance for floating point comparisons. 

309 output : callable 

310 A callable that takes a string, used (possibly repeatedly) to 

311 report inequalities. 

312 

313 Returns 

314 ------- 

315 isEqual : bool 

316 `True` if the fields are equal, `False` otherwise. 

317 

318 Notes 

319 ----- 

320 Floating point comparisons are performed by `numpy.allclose`. 

321 """ 

322 d1 = getattr(instance1, self.name) 

323 d2 = getattr(instance2, self.name) 

324 name = getComparisonName( 

325 _joinNamePath(instance1._name, self.name), 

326 _joinNamePath(instance2._name, self.name) 

327 ) 

328 if not compareScalars("isnone for %s" % name, d1 is None, d2 is None, output=output): 

329 return False 

330 if d1 is None and d2 is None: 

331 return True 

332 if not compareScalars("keys for %s" % name, set(d1.keys()), set(d2.keys()), output=output): 

333 return False 

334 equal = True 

335 for k, v1 in d1.items(): 

336 v2 = d2[k] 

337 result = compareScalars("%s[%r]" % (name, k), v1, v2, dtype=self.itemtype, 

338 rtol=rtol, atol=atol, output=output) 

339 if not result and shortcut: 

340 return False 

341 equal = equal and result 

342 return equal