Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/jwt/jwks_client.py: 26%

1import json 

2import urllib.request 

3from functools import lru_cache 

4from ssl import SSLContext 

5from typing import Any, Dict, List, Optional 

6from urllib.error import URLError 

7 

8from .api_jwk import PyJWK, PyJWKSet 

9from .api_jwt import decode_complete as decode_token 

10from .exceptions import PyJWKClientConnectionError, PyJWKClientError 

11from .jwk_set_cache import JWKSetCache 

12 

13 

14class PyJWKClient: 

15 def __init__( 

16 self, 

17 uri: str, 

18 cache_keys: bool = False, 

19 max_cached_keys: int = 16, 

20 cache_jwk_set: bool = True, 

21 lifespan: int = 300, 

22 headers: Optional[Dict[str, Any]] = None, 

23 timeout: int = 30, 

24 ssl_context: Optional[SSLContext] = None, 

25 ): 

26 if headers is None: 

27 headers = {} 

28 self.uri = uri 

29 self.jwk_set_cache: Optional[JWKSetCache] = None 

30 self.headers = headers 

31 self.timeout = timeout 

32 self.ssl_context = ssl_context 

33 

34 if cache_jwk_set: 

35 # Init jwt set cache with default or given lifespan. 

36 # Default lifespan is 300 seconds (5 minutes). 

37 if lifespan <= 0: 

38 raise PyJWKClientError( 

39 f'Lifespan must be greater than 0, the input is "{lifespan}"' 

40 ) 

41 self.jwk_set_cache = JWKSetCache(lifespan) 

42 else: 

43 self.jwk_set_cache = None 

44 

45 if cache_keys: 

46 # Cache signing keys 

47 # Ignore mypy (https://github.com/python/mypy/issues/2427) 

48 self.get_signing_key = lru_cache(maxsize=max_cached_keys)(self.get_signing_key) # type: ignore 

49 

50 def fetch_data(self) -> Any: 

51 jwk_set: Any = None 

52 try: 

53 r = urllib.request.Request(url=self.uri, headers=self.headers) 

54 with urllib.request.urlopen( 

55 r, timeout=self.timeout, context=self.ssl_context 

56 ) as response: 

57 jwk_set = json.load(response) 

58 except (URLError, TimeoutError) as e: 

59 raise PyJWKClientConnectionError( 

60 f'Fail to fetch data from the url, err: "{e}"' 

61 ) 

62 else: 

63 return jwk_set 

64 finally: 

65 if self.jwk_set_cache is not None: 

66 self.jwk_set_cache.put(jwk_set) 

67 

68 def get_jwk_set(self, refresh: bool = False) -> PyJWKSet: 

69 data = None 

70 if self.jwk_set_cache is not None and not refresh: 

71 data = self.jwk_set_cache.get() 

72 

73 if data is None: 

74 data = self.fetch_data() 

75 

76 if not isinstance(data, dict): 

77 raise PyJWKClientError("The JWKS endpoint did not return a JSON object") 

78 

79 return PyJWKSet.from_dict(data) 

80 

81 def get_signing_keys(self, refresh: bool = False) -> List[PyJWK]: 

82 jwk_set = self.get_jwk_set(refresh) 

83 signing_keys = [ 

84 jwk_set_key 

85 for jwk_set_key in jwk_set.keys 

86 if jwk_set_key.public_key_use in ["sig", None] and jwk_set_key.key_id 

87 ] 

88 

89 if not signing_keys: 

90 raise PyJWKClientError("The JWKS endpoint did not contain any signing keys") 

91 

92 return signing_keys 

93 

94 def get_signing_key(self, kid: str) -> PyJWK: 

95 signing_keys = self.get_signing_keys() 

96 signing_key = self.match_kid(signing_keys, kid) 

97 

98 if not signing_key: 

99 # If no matching signing key from the jwk set, refresh the jwk set and try again. 

100 signing_keys = self.get_signing_keys(refresh=True) 

101 signing_key = self.match_kid(signing_keys, kid) 

102 

103 if not signing_key: 

104 raise PyJWKClientError( 

105 f'Unable to find a signing key that matches: "{kid}"' 

106 ) 

107 

108 return signing_key 

109 

110 def get_signing_key_from_jwt(self, token: str) -> PyJWK: 

111 unverified = decode_token(token, options={"verify_signature": False}) 

112 header = unverified["header"] 

113 return self.get_signing_key(header.get("kid")) 

114 

115 @staticmethod 

116 def match_kid(signing_keys: List[PyJWK], kid: str) -> Optional[PyJWK]: 

117 signing_key = None 

118 

119 for key in signing_keys: 

120 if key.key_id == kid: 

121 signing_key = key 

122 break 

123 

124 return signing_key