Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/fastavro/_schema_common.py: 48%

1import hashlib 

2 

3 

4PRIMITIVES = { 

5 "boolean", 

6 "bytes", 

7 "double", 

8 "float", 

9 "int", 

10 "long", 

11 "null", 

12 "string", 

13} 

14 

15RESERVED_PROPERTIES = { 

16 "type", 

17 "name", 

18 "namespace", 

19 "fields", # Record 

20 "items", # Array 

21 "size", # Fixed 

22 "symbols", # Enum 

23 "values", # Map 

24 "doc", 

25} 

26 

27OPTIONAL_FIELD_PROPERTIES = { 

28 "doc", 

29 "aliases", 

30 "default", 

31} 

32 

33RESERVED_FIELD_PROPERTIES = {"type", "name"} | OPTIONAL_FIELD_PROPERTIES 

34 

35RABIN_64 = "CRC-64-AVRO" 

36JAVA_FINGERPRINT_MAPPING = {"SHA-256": "sha256", "MD5": "md5"} 

37FINGERPRINT_ALGORITHMS = ( 

38 hashlib.algorithms_guaranteed | JAVA_FINGERPRINT_MAPPING.keys() | {RABIN_64} 

39) 

40 

41 

42class UnknownType(ValueError): 

43 def __init__(self, name): 

44 super().__init__(name) 

45 self.name = name 

46 

47 

48class SchemaParseException(Exception): 

49 pass 

50 

51 

52def rabin_fingerprint(data): 

53 empty_64 = 0xC15D213AA4D7A795 

54 

55 fp_table = [] 

56 for i in range(256): 

57 fp = i 

58 for j in range(8): 

59 mask = -(fp & 1) 

60 fp = (fp >> 1) ^ (empty_64 & mask) 

61 fp_table.append(fp) 

62 

63 result = empty_64 

64 for byte in data: 

65 result = (result >> 8) ^ fp_table[(result ^ byte) & 0xFF] 

66 

67 # Although not mentioned in the Avro specification, the Java 

68 # implementation gives fingerprint bytes in little-endian order 

69 return result.to_bytes(length=8, byteorder="little", signed=False).hex()