Raise exception when required cryptography dependency is missing

jwt/api_jwk.py

@@ -5,7 +5,13 @@
 from typing import Any
 
 from .algorithms import get_default_algorithms, has_crypto, requires_cryptography
-from .exceptions import InvalidKeyError, PyJWKError, PyJWKSetError, PyJWTError
+from .exceptions import (
+    InvalidKeyError,
+    MissingCryptographyError,
+    PyJWKError,
+    PyJWKSetError,
+    PyJWTError,
+)
 from .types import JWKDict
 
 
@@ -50,7 +56,9 @@
                 raise InvalidKeyError(f"Unsupported kty: {kty}")
 
         if not has_crypto and algorithm in requires_cryptography:
-            raise PyJWKError(f"{algorithm} requires 'cryptography' to be installed.")
+            raise MissingCryptographyError(
+                f"{algorithm} requires 'cryptography' to be installed."
+            )
 
         self.algorithm_name = algorithm
 
@@ -96,7 +104,9 @@
         for key in keys:
             try:
                 self.keys.append(PyJWK(key))
-            except PyJWTError:
+            except PyJWTError as error:
+                if isinstance(error, MissingCryptographyError):
+                    raise error
                 # skip unusable keys
                 continue
 

jwt/exceptions.py

@@ -58,6 +58,10 @@ class PyJWKError(PyJWTError):
     pass
 
 
+class MissingCryptographyError(PyJWKError):
+    pass
+
+
 class PyJWKSetError(PyJWTError):
     pass