Coverage for presidio_analyzer / predefined_recognizers / country_specific / us / us_ssn_recognizer.py: 100%

1from collections import defaultdict 

2from typing import List, Optional 

3 

4from presidio_analyzer import Pattern, PatternRecognizer 

5 

6 

7class UsSsnRecognizer(PatternRecognizer): 

8 """Recognize US Social Security Number (SSN) using regex. 

9 

10 :param patterns: List of patterns to be used by this recognizer 

11 :param context: List of context words to increase confidence in detection 

12 :param supported_language: Language this recognizer supports 

13 :param supported_entity: The entity this recognizer can detect 

14 """ 

15 

16 PATTERNS = [ 

17 Pattern("SSN1 (very weak)", r"\b([0-9]{5})-([0-9]{4})\b", 0.05), 

18 Pattern("SSN2 (very weak)", r"\b([0-9]{3})-([0-9]{6})\b", 0.05), 

19 Pattern("SSN3 (very weak)", r"\b(([0-9]{3})-([0-9]{2})-([0-9]{4}))\b", 0.05), 

20 Pattern("SSN4 (very weak)", r"\b[0-9]{9}\b", 0.05), 

21 Pattern("SSN5 (medium)", r"\b([0-9]{3})[- .]([0-9]{2})[- .]([0-9]{4})\b", 0.5), 

22 ] 

23 

24 CONTEXT = [ 

25 "social", 

26 "security", 

27 # "sec", # Task #603: Support keyphrases ("social sec") 

28 "ssn", 

29 "ssns", 

30 # "ssn#", # iss:1452 - a # does not work with LemmaContextAwareEnhancer 

31 # "ss#", # iss:1452 - a # does not work with LemmaContextAwareEnhancer 

32 "ssid", 

33 ] 

34 

35 def __init__( 

36 self, 

37 patterns: Optional[List[Pattern]] = None, 

38 context: Optional[List[str]] = None, 

39 supported_language: str = "en", 

40 supported_entity: str = "US_SSN", 

41 name: Optional[str] = None, 

42 ): 

43 patterns = patterns if patterns else self.PATTERNS 

44 context = context if context else self.CONTEXT 

45 super().__init__( 

46 supported_entity=supported_entity, 

47 patterns=patterns, 

48 context=context, 

49 supported_language=supported_language, 

50 name=name, 

51 ) 

52 

53 def invalidate_result(self, pattern_text: str) -> bool: 

54 """ 

55 Check if the pattern text cannot be validated as a US_SSN entity. 

56 

57 :param pattern_text: Text detected as pattern by regex 

58 :return: True if invalidated 

59 """ 

60 # if there are delimiters, make sure both delimiters are the same 

61 delimiter_counts = defaultdict(int) 

62 for c in pattern_text: 

63 if c in (".", "-", " "): 

64 delimiter_counts[c] += 1 

65 if len(delimiter_counts.keys()) > 1: 

66 # mismatched delimiters 

67 return True 

68 

69 only_digits = "".join(c for c in pattern_text if c.isdigit()) 

70 if all(only_digits[0] == c for c in only_digits): 

71 # cannot be all same digit 

72 return True 

73 

74 if only_digits[3:5] == "00" or only_digits[5:] == "0000": 

75 # groups cannot be all zeros 

76 return True 

77 

78 for sample_ssn in ("000", "666", "123456789", "98765432", "078051120"): 

79 if only_digits.startswith(sample_ssn): 

80 return True 

81 

82 return False