Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/c7n/filters/core.py: 25%

1# Copyright The Cloud Custodian Authors. 

2# SPDX-License-Identifier: Apache-2.0 

3""" 

4Resource Filtering Logic 

5""" 

6import copy 

7import datetime 

8from datetime import timedelta 

9import fnmatch 

10import ipaddress 

11import logging 

12import operator 

13import re 

14 

15from dateutil.tz import tzutc 

16from dateutil.parser import parse 

17from c7n.vendored.distutils import version 

18from random import sample 

19 

20from c7n.element import Element 

21from c7n.exceptions import PolicyValidationError, PolicyExecutionError 

22from c7n.manager import ResourceManager 

23from c7n.registry import PluginRegistry 

24from c7n.resolver import ValuesFrom 

25from c7n.utils import ( 

26 set_annotation, 

27 type_schema, 

28 parse_cidr, 

29 parse_date, 

30 jmespath_search, 

31 jmespath_compile 

32) 

33from c7n.manager import iter_filters 

34 

35 

36class FilterValidationError(Exception): 

37 pass 

38 

39 

40# Matching filters annotate their key onto objects 

41ANNOTATION_KEY = "c7n:MatchedFilters" 

42 

43 

44def glob_match(value, pattern): 

45 if not isinstance(value, str): 

46 return False 

47 return fnmatch.fnmatch(value, pattern) 

48 

49 

50def regex_match(value, regex): 

51 if not isinstance(value, str): 

52 return False 

53 # Note python 2.5+ internally cache regex 

54 # would be nice to use re2 

55 return bool(re.match(regex, value, flags=re.IGNORECASE)) 

56 

57 

58def regex_case_sensitive_match(value, regex): 

59 if not isinstance(value, str): 

60 return False 

61 # Note python 2.5+ internally cache regex 

62 # would be nice to use re2 

63 return bool(re.match(regex, value)) 

64 

65 

66def operator_in(x, y): 

67 return x in y 

68 

69 

70def operator_ni(x, y): 

71 return x not in y 

72 

73 

74def difference(x, y): 

75 return bool(set(x).difference(y)) 

76 

77 

78def intersect(x, y): 

79 return bool(set(x).intersection(y)) 

80 

81 

82def mod(x, y): 

83 return bool(x % y) 

84 

85 

86OPERATORS = { 

87 'eq': operator.eq, 

88 'equal': operator.eq, 

89 'ne': operator.ne, 

90 'not-equal': operator.ne, 

91 'gt': operator.gt, 

92 'greater-than': operator.gt, 

93 'ge': operator.ge, 

94 'gte': operator.ge, 

95 'le': operator.le, 

96 'lte': operator.le, 

97 'lt': operator.lt, 

98 'less-than': operator.lt, 

99 'glob': glob_match, 

100 'regex': regex_match, 

101 'regex-case': regex_case_sensitive_match, 

102 'in': operator_in, 

103 'ni': operator_ni, 

104 'not-in': operator_ni, 

105 'contains': operator.contains, 

106 'difference': difference, 

107 'intersect': intersect, 

108 'mod': mod} 

109 

110 

111VALUE_TYPES = [ 

112 'age', 'integer', 'expiration', 'normalize', 'size', 

113 'cidr', 'cidr_size', 'swap', 'resource_count', 'expr', 

114 'unique_size', 'date', 'version', 'float'] 

115 

116 

117class FilterRegistry(PluginRegistry): 

118 

119 value_filter_class = None 

120 

121 def __init__(self, *args, **kw): 

122 super().__init__(*args, **kw) 

123 self.register('value', ValueFilter) 

124 self.register('or', Or) 

125 self.register('and', And) 

126 self.register('not', Not) 

127 self.register('event', EventFilter) 

128 self.register('reduce', ReduceFilter) 

129 self.register('list-item', ListItemFilter) 

130 

131 def parse(self, data, manager): 

132 results = [] 

133 for d in data: 

134 results.append(self.factory(d, manager)) 

135 return results 

136 

137 def factory(self, data, manager=None): 

138 """Factory func for filters. 

139 

140 data - policy config for filters 

141 manager - resource type manager (ec2, s3, etc) 

142 """ 

143 

144 # Make the syntax a little nicer for common cases. 

145 if isinstance(data, dict) and len(data) == 1 and 'type' not in data: 

146 op = list(data.keys())[0] 

147 if op == 'or': 

148 return self['or'](data, self, manager) 

149 elif op == 'and': 

150 return self['and'](data, self, manager) 

151 elif op == 'not': 

152 return self['not'](data, self, manager) 

153 return self.value_filter_class(data, manager) 

154 if isinstance(data, str): 

155 filter_type = data 

156 data = {'type': data} 

157 else: 

158 filter_type = data.get('type') 

159 if not filter_type: 

160 raise PolicyValidationError( 

161 "%s Invalid Filter %s" % ( 

162 self.plugin_type, data)) 

163 filter_class = self.get(filter_type) 

164 if filter_class is not None: 

165 return filter_class(data, manager) 

166 else: 

167 raise PolicyValidationError( 

168 "%s Invalid filter type %s" % ( 

169 self.plugin_type, data)) 

170 

171 

172def trim_runtime(filters): 

173 """Remove runtime filters. 

174 

175 Some filters can only be effectively evaluated at policy 

176 execution, ie. event filters. 

177 

178 When evaluating conditions for dryrun or provisioning stages we 

179 remove them. 

180 """ 

181 def remove_filter(f): 

182 block = f.get_block_parent() 

183 block.filters.remove(f) 

184 if isinstance(block, BooleanGroupFilter) and not len(block): 

185 remove_filter(block) 

186 

187 for f in iter_filters(filters): 

188 if isinstance(f, EventFilter): 

189 remove_filter(f) 

190 

191 

192# Really should be an abstract base class (abc) or 

193# zope.interface 

194 

195class Filter(Element): 

196 

197 log = logging.getLogger('custodian.filters') 

198 

199 def __init__(self, data, manager=None): 

200 self.data = data 

201 self.manager = manager 

202 

203 def process(self, resources, event=None): 

204 """ Bulk process resources and return filtered set.""" 

205 return list(filter(self, resources)) 

206 

207 def get_block_operator(self): 

208 """Determine the immediate parent boolean operator for a filter""" 

209 # Top level operator is `and` 

210 block = self.get_block_parent() 

211 if block.type in ('and', 'or', 'not'): 

212 return block.type 

213 return 'and' 

214 

215 def get_block_parent(self): 

216 """Get the block parent for a filter""" 

217 block_stack = [self.manager] 

218 for f in self.manager.iter_filters(block_end=True): 

219 if f is None: 

220 block_stack.pop() 

221 elif f == self: 

222 return block_stack[-1] 

223 elif f.type in ('and', 'or', 'not'): 

224 block_stack.append(f) 

225 

226 def merge_annotation(self, r, annotation_key, values): 

227 block_op = self.get_block_operator() 

228 if block_op in ('and', 'not'): 

229 r[self.matched_annotation_key] = intersect_list( 

230 values, 

231 r.get(self.matched_annotation_key)) 

232 elif block_op == 'or': 

233 r[self.matched_annotation_key] = union_list( 

234 values, 

235 r.get(self.matched_annotation_key)) 

236 

237 

238class BaseValueFilter(Filter): 

239 expr = None 

240 

241 def __init__(self, data, manager=None): 

242 super(BaseValueFilter, self).__init__(data, manager) 

243 self.expr = {} 

244 

245 def get_resource_value(self, k, i, regex=None): 

246 r = None 

247 if k.startswith('tag:'): 

248 tk = k.split(':', 1)[1] 

249 if 'Tags' in i: 

250 for t in i.get("Tags", []): 

251 if t.get('Key') == tk: 

252 r = t.get('Value') 

253 break 

254 # GCP schema: 'labels': {'key': 'value'} 

255 elif 'labels' in i: 

256 r = i.get('labels', {}).get(tk, None) 

257 # GCP has a secondary form of labels called tags 

258 # as labels without values. 

259 # Azure schema: 'tags': {'key': 'value'} 

260 elif 'tags' in i: 

261 r = (i.get('tags', {}) or {}).get(tk, None) 

262 elif k in i: 

263 r = i.get(k) 

264 elif k not in self.expr: 

265 self.expr[k] = jmespath_compile(k) 

266 r = self.expr[k].search(i) 

267 else: 

268 r = self.expr[k].search(i) 

269 

270 if regex: 

271 r = ValueRegex(regex).get_resource_value(r) 

272 return r 

273 

274 def _validate_value_regex(self, regex): 

275 """Specific validation for `value_regex` type 

276 

277 The `value_regex` type works a little differently. In 

278 particular it doesn't support OPERATORS that perform 

279 operations on a list of values, specifically 'intersect', 

280 'contains', 'difference', 'in' and 'not-in' 

281 """ 

282 # Sanity check that we can compile 

283 try: 

284 pattern = re.compile(regex) 

285 if pattern.groups != 1: 

286 raise PolicyValidationError( 

287 "value_regex must have a single capturing group: %s" % 

288 self.data) 

289 except re.error as e: 

290 raise PolicyValidationError( 

291 "Invalid value_regex: %s %s" % (e, self.data)) 

292 return self 

293 

294 

295def intersect_list(a, b): 

296 if b is None: 

297 return a 

298 elif a is None: 

299 return b 

300 res = [] 

301 for x in a: 

302 if x in b: 

303 res.append(x) 

304 return res 

305 

306 

307def union_list(a, b): 

308 if not b: 

309 return a 

310 if not a: 

311 return b 

312 res = a 

313 res.extend(x for x in b if x not in a) 

314 return res 

315 

316 

317class BooleanGroupFilter(Filter): 

318 

319 def __init__(self, data, registry, manager): 

320 super(BooleanGroupFilter, self).__init__(data) 

321 self.registry = registry 

322 self.filters = registry.parse(list(self.data.values())[0], manager) 

323 self.manager = manager 

324 

325 def validate(self): 

326 for f in self.filters: 

327 f.validate() 

328 return self 

329 

330 def get_resource_type_id(self): 

331 resource_type = self.manager.get_model() 

332 return resource_type.id 

333 

334 def __len__(self): 

335 return len(self.filters) 

336 

337 def __bool__(self): 

338 return True 

339 

340 def get_deprecations(self): 

341 """Return any matching deprecations for the nested filters.""" 

342 deprecations = [] 

343 for f in self.filters: 

344 deprecations.extend(f.get_deprecations()) 

345 return deprecations 

346 

347 

348class Or(BooleanGroupFilter): 

349 

350 def process(self, resources, event=None): 

351 if self.manager: 

352 return self.process_set(resources, event) 

353 return super(Or, self).process(resources, event) 

354 

355 def __call__(self, r): 

356 """Fallback for older unit tests that don't utilize a query manager""" 

357 for f in self.filters: 

358 if f(r): 

359 return True 

360 return False 

361 

362 def process_set(self, resources, event): 

363 rtype_id = self.get_resource_type_id() 

364 compiled = None 

365 if '.' in rtype_id: 

366 compiled = jmespath_compile(rtype_id) 

367 resource_map = {compiled.search(r): r for r in resources} 

368 else: 

369 resource_map = {r[rtype_id]: r for r in resources} 

370 results = set() 

371 for f in self.filters: 

372 if compiled: 

373 results = results.union([ 

374 compiled.search(r) for r in f.process(resources, event)]) 

375 else: 

376 results = results.union([ 

377 r[rtype_id] for r in f.process(resources, event)]) 

378 return [resource_map[r_id] for r_id in results] 

379 

380 

381class And(BooleanGroupFilter): 

382 

383 def process(self, resources, events=None): 

384 if self.manager: 

385 sweeper = AnnotationSweeper(self.get_resource_type_id(), resources) 

386 

387 for f in self.filters: 

388 resources = f.process(resources, events) 

389 if not resources: 

390 break 

391 

392 if self.manager: 

393 sweeper.sweep(resources) 

394 

395 return resources 

396 

397 

398class Not(BooleanGroupFilter): 

399 

400 def process(self, resources, event=None): 

401 if self.manager: 

402 return self.process_set(resources, event) 

403 return super(Not, self).process(resources, event) 

404 

405 def __call__(self, r): 

406 """Fallback for older unit tests that don't utilize a query manager""" 

407 

408 # There is an implicit 'and' for self.filters 

409 # ~(A ^ B ^ ... ^ Z) = ~A v ~B v ... v ~Z 

410 for f in self.filters: 

411 if not f(r): 

412 return True 

413 return False 

414 

415 def process_set(self, resources, event): 

416 rtype_id = self.get_resource_type_id() 

417 compiled = None 

418 if '.' in rtype_id: 

419 compiled = jmespath_compile(rtype_id) 

420 resource_map = {compiled.search(r): r for r in resources} 

421 else: 

422 resource_map = {r[rtype_id]: r for r in resources} 

423 sweeper = AnnotationSweeper(rtype_id, resources) 

424 

425 for f in self.filters: 

426 resources = f.process(resources, event) 

427 if not resources: 

428 break 

429 

430 before = set(resource_map.keys()) 

431 if compiled: 

432 after = {compiled.search(r) for r in resources} 

433 else: 

434 after = {r[rtype_id] for r in resources} 

435 results = before - after 

436 sweeper.sweep([]) 

437 

438 return [resource_map[r_id] for r_id in results] 

439 

440 

441class AnnotationSweeper: 

442 """Support clearing annotations set within a block filter. 

443 

444 See https://github.com/cloud-custodian/cloud-custodian/issues/2116 

445 """ 

446 def __init__(self, id_key, resources): 

447 self.id_key = id_key 

448 ra_map = {} 

449 resource_map = {} 

450 compiled = None 

451 if '.' in id_key: 

452 compiled = jmespath_compile(self.id_key) 

453 for r in resources: 

454 if compiled: 

455 id_ = compiled.search(r) 

456 else: 

457 id_ = r[self.id_key] 

458 ra_map[id_] = {k: v for k, v in r.items() if k.startswith('c7n')} 

459 resource_map[id_] = r 

460 # We keep a full copy of the annotation keys to allow restore. 

461 self.ra_map = copy.deepcopy(ra_map) 

462 self.resource_map = resource_map 

463 

464 def sweep(self, resources): 

465 compiled = None 

466 if '.' in self.id_key: 

467 compiled = jmespath_compile(self.id_key) 

468 diff = set(self.ra_map).difference([compiled.search(r) for r in resources]) 

469 else: 

470 diff = set(self.ra_map).difference([r[self.id_key] for r in resources]) 

471 for rid in diff: 

472 # Clear annotations if the block filter didn't match 

473 akeys = [k for k in self.resource_map[rid] if k.startswith('c7n')] 

474 for k in akeys: 

475 del self.resource_map[rid][k] 

476 # Restore annotations that may have existed prior to the block filter. 

477 self.resource_map[rid].update(self.ra_map[rid]) 

478 

479 

480# The default LooseVersion will fail on comparing present strings, used 

481# in the value as shorthand for certain options. 

482class ComparableVersion(version.LooseVersion): 

483 def __eq__(self, other): 

484 try: 

485 return super(ComparableVersion, self).__eq__(other) 

486 except TypeError: 

487 return False 

488 

489 

490class ValueFilter(BaseValueFilter): 

491 """Generic value filter using jmespath 

492 """ 

493 op = v = vtype = None 

494 

495 schema = { 

496 'type': 'object', 

497 # Doesn't mix well with inherits that extend 

498 'additionalProperties': False, 

499 'required': ['type'], 

500 'properties': { 

501 # Doesn't mix well as enum with inherits that extend 

502 'type': {'enum': ['value']}, 

503 'key': {'type': 'string'}, 

504 'value_type': {'$ref': '#/definitions/filters_common/value_types'}, 

505 'default': {'type': 'object'}, 

506 'value_regex': {'type': 'string'}, 

507 'value_from': {'$ref': '#/definitions/filters_common/value_from'}, 

508 'value': {'$ref': '#/definitions/filters_common/value'}, 

509 'op': {'$ref': '#/definitions/filters_common/comparison_operators'}, 

510 'value_path': {'type': 'string'} 

511 } 

512 } 

513 schema_alias = True 

514 annotate = True 

515 required_keys = {'value', 'key'} 

516 

517 def _validate_resource_count(self): 

518 """ Specific validation for `resource_count` type 

519 

520 The `resource_count` type works a little differently because it operates 

521 on the entire set of resources. It: 

522 - does not require `key` 

523 - `value` must be a number 

524 - supports a subset of the OPERATORS list 

525 """ 

526 for field in ('op', 'value'): 

527 if field not in self.data: 

528 raise PolicyValidationError( 

529 "Missing '%s' in value filter %s" % (field, self.data)) 

530 

531 if not (isinstance(self.data['value'], int) or 

532 isinstance(self.data['value'], list)): 

533 raise PolicyValidationError( 

534 "`value` must be an integer in resource_count filter %s" % self.data) 

535 

536 # I don't see how to support regex for this? 

537 if (self.data['op'] not in OPERATORS or 

538 self.data['op'] in {'regex', 'regex-case'} or 

539 'value_regex' in self.data): 

540 raise PolicyValidationError( 

541 "Invalid operator in value filter %s" % self.data) 

542 

543 return self 

544 

545 def validate(self): 

546 if len(self.data) == 1: 

547 return self 

548 

549 # `resource_count` requires a slightly different schema than the rest of 

550 # the value filters because it operates on the full resource list 

551 if self.data.get('value_type') == 'resource_count': 

552 return self._validate_resource_count() 

553 elif self.data.get('value_type') == 'date': 

554 if not parse_date(self.data.get('value')): 

555 raise PolicyValidationError( 

556 "value_type: date with invalid date value:%s", 

557 self.data.get('value', '')) 

558 if 'key' not in self.data and 'key' in self.required_keys: 

559 raise PolicyValidationError( 

560 "Missing 'key' in value filter %s" % self.data) 

561 if ('value' not in self.data and 

562 'value_from' not in self.data and 

563 'value_path' not in self.data and 

564 'value' in self.required_keys): 

565 raise PolicyValidationError( 

566 "Missing 'value' in value filter %s" % self.data) 

567 if 'op' in self.data: 

568 if self.data['op'] not in OPERATORS: 

569 raise PolicyValidationError( 

570 "Invalid operator in value filter %s" % self.data) 

571 if self.data['op'] in {'regex', 'regex-case'}: 

572 # Sanity check that we can compile 

573 try: 

574 re.compile(self.data['value']) 

575 except re.error as e: 

576 raise PolicyValidationError( 

577 "Invalid regex: %s %s" % (e, self.data)) 

578 if 'value_regex' in self.data: 

579 return self._validate_value_regex(self.data['value_regex']) 

580 

581 return self 

582 

583 def __call__(self, i): 

584 if self.data.get('value_type') == 'resource_count': 

585 return self.process(i) 

586 

587 matched = self.match(i) 

588 if matched and self.annotate: 

589 set_annotation(i, ANNOTATION_KEY, self.k) 

590 return matched 

591 

592 def process(self, resources, event=None): 

593 # For the resource_count filter we operate on the full set of resources. 

594 if self.data.get('value_type') == 'resource_count': 

595 op = OPERATORS[self.data.get('op')] 

596 if op(len(resources), self.data.get('value')): 

597 return resources 

598 return [] 

599 

600 return super(ValueFilter, self).process(resources, event) 

601 

602 def get_resource_value(self, k, i): 

603 return super(ValueFilter, self).get_resource_value(k, i, self.data.get('value_regex')) 

604 

605 def get_path_value(self, i): 

606 """Retrieve values using JMESPath. 

607 

608 When using a Value Filter, a ``value_path`` can be specified. 

609 This means the value(s) the filter will compare against are 

610 calculated during the initialization of the filter. 

611 

612 Note that this option only pulls properties of the resource 

613 currently being filtered. 

614 

615 .. code-block:: yaml 

616 - name: find-admins-with-user-roles 

617 resource: gcp.project 

618 filters: 

619 - type: iam-policy 

620 doc: 

621 key: bindings[?(role=='roles/admin')].members[] 

622 op: intersect 

623 value_path: bindings[?(role=='roles/user_access')].members[] 

624 

625 The iam-policy use the implementation of the generic Value Filter. 

626 This implementation allows for the comparison of two separate lists of values 

627 within the same resource. 

628 """ 

629 return jmespath_search(self.data.get('value_path'), i) 

630 

631 def match(self, i): 

632 if self.v is None and len(self.data) == 1: 

633 [(self.k, self.v)] = self.data.items() 

634 elif self.v is None and not hasattr(self, 'content_initialized'): 

635 self.k = self.data.get('key') 

636 self.op = self.data.get('op') 

637 if 'value_from' in self.data: 

638 values = ValuesFrom(self.data['value_from'], self.manager) 

639 self.v = values.get_values() 

640 elif 'value_path' in self.data: 

641 self.v = self.get_path_value(i) 

642 else: 

643 self.v = self.data.get('value') 

644 self.content_initialized = True 

645 self.vtype = self.data.get('value_type') 

646 

647 if i is None: 

648 return False 

649 

650 # value extract 

651 r = self.get_resource_value(self.k, i) 

652 if self.op in ('in', 'not-in') and r is None: 

653 r = () 

654 

655 # value type conversion 

656 if self.vtype is not None: 

657 v, r = self.process_value_type(self.v, r, i) 

658 else: 

659 v = self.v 

660 

661 # Value match 

662 if r is None and v == 'absent': 

663 return True 

664 elif r is not None and v == 'present': 

665 return True 

666 elif v == 'not-null' and r: 

667 return True 

668 elif v == 'empty' and not r: 

669 return True 

670 elif self.op: 

671 op = OPERATORS[self.op] 

672 try: 

673 return op(r, v) 

674 except TypeError: 

675 return False 

676 elif r == v: 

677 return True 

678 

679 return False 

680 

681 def process_value_type(self, sentinel, value, resource): 

682 if self.vtype == 'normalize' and isinstance(value, str): 

683 return sentinel, value.strip().lower() 

684 

685 elif self.vtype == 'expr': 

686 sentinel = self.get_resource_value(sentinel, resource) 

687 return sentinel, value 

688 

689 elif self.vtype == 'integer': 

690 try: 

691 value = int(str(value).strip()) 

692 except ValueError: 

693 value = 0 

694 elif self.vtype == 'float': 

695 try: 

696 value = float(str(value).strip()) 

697 except ValueError: 

698 value = 0.0 

699 elif self.vtype == 'size': 

700 try: 

701 return sentinel, len(value) 

702 except TypeError: 

703 return sentinel, 0 

704 elif self.vtype == 'unique_size': 

705 try: 

706 return sentinel, len(set(value)) 

707 except TypeError: 

708 return sentinel, 0 

709 elif self.vtype == 'swap': 

710 return value, sentinel 

711 elif self.vtype == 'date': 

712 return parse_date(sentinel), parse_date(value) 

713 elif self.vtype == 'age': 

714 if not isinstance(sentinel, datetime.datetime): 

715 sentinel = datetime.datetime.now(tz=tzutc()) - timedelta(sentinel) 

716 value = parse_date(value) 

717 if value is None: 

718 # compatiblity 

719 value = 0 

720 # Reverse the age comparison, we want to compare the value being 

721 # greater than the sentinel typically. Else the syntax for age 

722 # comparisons is intuitively wrong. 

723 return value, sentinel 

724 elif self.vtype == 'cidr': 

725 s = parse_cidr(sentinel) 

726 v = parse_cidr(value) 

727 if (isinstance(s, ipaddress._BaseAddress) and isinstance(v, ipaddress._BaseNetwork)): 

728 return v, s 

729 return s, v 

730 elif self.vtype == 'cidr_size': 

731 cidr = parse_cidr(value) 

732 if cidr: 

733 return sentinel, cidr.prefixlen 

734 return sentinel, 0 

735 

736 # Allows for expiration filtering, for events in the future as opposed 

737 # to events in the past which age filtering allows for. 

738 elif self.vtype == 'expiration': 

739 if not isinstance(sentinel, datetime.datetime): 

740 sentinel = datetime.datetime.now(tz=tzutc()) + timedelta(sentinel) 

741 value = parse_date(value) 

742 if value is None: 

743 value = 0 

744 return sentinel, value 

745 

746 # Allows for comparing version numbers, for things that you expect a minimum version number. 

747 elif self.vtype == 'version': 

748 s = ComparableVersion(sentinel) 

749 v = ComparableVersion(value) 

750 return s, v 

751 

752 return sentinel, value 

753 

754 

755FilterRegistry.value_filter_class = ValueFilter 

756 

757 

758class AgeFilter(Filter): 

759 """Automatically filter resources older than a given date. 

760 

761 **Deprecated** use a value filter with `value_type: age` which can be 

762 done on any attribute. 

763 """ 

764 threshold_date = None 

765 

766 # The name of attribute to compare to threshold; must override in subclass 

767 date_attribute = None 

768 

769 schema = None 

770 

771 def validate(self): 

772 if not self.date_attribute: 

773 raise NotImplementedError( 

774 "date_attribute must be overriden in subclass") 

775 return self 

776 

777 def get_resource_date(self, i): 

778 v = i[self.date_attribute] 

779 if not isinstance(v, datetime.datetime): 

780 v = parse(v) 

781 if not v.tzinfo: 

782 v = v.replace(tzinfo=tzutc()) 

783 return v 

784 

785 def __call__(self, i): 

786 v = self.get_resource_date(i) 

787 if v is None: 

788 return False 

789 op = OPERATORS[self.data.get('op', 'greater-than')] 

790 

791 if not self.threshold_date: 

792 

793 days = self.data.get('days', 0) 

794 hours = self.data.get('hours', 0) 

795 minutes = self.data.get('minutes', 0) 

796 # Work around placebo issues with tz 

797 if v.tzinfo: 

798 n = datetime.datetime.now(tz=tzutc())