B904 Exception fixes

jwt/algorithms.py

@@ -297,7 +297,7 @@ def from_jwk(jwk: str | JWKDict) -> bytes:
             else:
                 raise ValueError
         except ValueError:
-            raise InvalidKeyError("Key is not valid JSON")
+            raise InvalidKeyError("Key is not valid JSON") from None
 
         if obj.get("kty") != "oct":
             raise InvalidKeyError("Not an HMAC key")
@@ -346,7 +346,7 @@ def prepare_key(self, key: AllowedRSAKeys | str | bytes) -> AllowedRSAKeys:
                 try:
                     return cast(RSAPublicKey, load_pem_public_key(key_bytes))
                 except (ValueError, UnsupportedAlgorithm):
-                    raise InvalidKeyError("Could not parse the provided public key.")
+                    raise InvalidKeyError("Could not parse the provided public key.") from None
 
         @overload
         @staticmethod
@@ -409,10 +409,10 @@ def from_jwk(jwk: str | JWKDict) -> AllowedRSAKeys:
                 else:
                     raise ValueError
             except ValueError:
-                raise InvalidKeyError("Key is not valid JSON")
+                raise InvalidKeyError("Key is not valid JSON") from None
 
             if obj.get("kty") != "RSA":
-                raise InvalidKeyError("Not an RSA key")
+                raise InvalidKeyError("Not an RSA key") from None
 
             if "d" in obj and "e" in obj and "n" in obj:
                 # Private key
@@ -428,7 +428,7 @@ def from_jwk(jwk: str | JWKDict) -> AllowedRSAKeys:
                 if any_props_found and not all(props_found):
                     raise InvalidKeyError(
                         "RSA key must include all parameters if any are present besides d"
-                    )
+                    ) from None
 
                 public_numbers = RSAPublicNumbers(
                     from_base64url_uint(obj["e"]),
@@ -520,7 +520,7 @@ def prepare_key(self, key: AllowedECKeys | str | bytes) -> AllowedECKeys:
             ):
                 raise InvalidKeyError(
                     "Expecting a EllipticCurvePrivateKey/EllipticCurvePublicKey. Wrong key provided for ECDSA algorithms"
-                )
+                ) from None
 
             return crypto_key
 
@@ -605,13 +605,13 @@ def from_jwk(jwk: str | JWKDict) -> AllowedECKeys:
                 else:
                     raise ValueError
             except ValueError:
-                raise InvalidKeyError("Key is not valid JSON")
+                raise InvalidKeyError("Key is not valid JSON") from None
 
             if obj.get("kty") != "EC":
-                raise InvalidKeyError("Not an Elliptic curve key")
+                raise InvalidKeyError("Not an Elliptic curve key") from None
 
             if "x" not in obj or "y" not in obj:
-                raise InvalidKeyError("Not an Elliptic curve key")
+                raise InvalidKeyError("Not an Elliptic curve key") from None
 
             x = base64url_decode(obj.get("x"))
             y = base64url_decode(obj.get("y"))
@@ -623,17 +623,17 @@ def from_jwk(jwk: str | JWKDict) -> AllowedECKeys:
                 if len(x) == len(y) == 32:
                     curve_obj = SECP256R1()
                 else:
-                    raise InvalidKeyError("Coords should be 32 bytes for curve P-256")
+                    raise InvalidKeyError("Coords should be 32 bytes for curve P-256") from None
             elif curve == "P-384":
                 if len(x) == len(y) == 48:
                     curve_obj = SECP384R1()
                 else:
-                    raise InvalidKeyError("Coords should be 48 bytes for curve P-384")
+                    raise InvalidKeyError("Coords should be 48 bytes for curve P-384") from None
             elif curve == "P-521":
                 if len(x) == len(y) == 66:
                     curve_obj = SECP521R1()
                 else:
-                    raise InvalidKeyError("Coords should be 66 bytes for curve P-521")
+                    raise InvalidKeyError("Coords should be 66 bytes for curve P-521") from None
             elif curve == "secp256k1":
                 if len(x) == len(y) == 32:
                     curve_obj = SECP256K1()
@@ -834,7 +834,7 @@ def from_jwk(jwk: str | JWKDict) -> AllowedOKPKeys:
                 else:
                     raise ValueError
             except ValueError:
-                raise InvalidKeyError("Key is not valid JSON")
+                raise InvalidKeyError("Key is not valid JSON") from None
 
             if obj.get("kty") != "OKP":
                 raise InvalidKeyError("Not an Octet Key Pair")

jwt/api_jws.py

@@ -299,7 +299,7 @@ def _verify_signature(
         try:
             alg = header["alg"]
         except KeyError:
-            raise InvalidAlgorithmError("Algorithm not specified")
+            raise InvalidAlgorithmError("Algorithm not specified") from None
 
         if not alg or (algorithms is not None and alg not in algorithms):
             raise InvalidAlgorithmError("The specified alg value is not allowed")

jwt/api_jwt.py

@@ -173,7 +173,7 @@ def _decode_payload(self, decoded: dict[str, Any]) -> Any:
         try:
             payload = json.loads(decoded["payload"])
         except ValueError as e:
-            raise DecodeError(f"Invalid payload string: {e}")
+            raise DecodeError(f"Invalid payload string: {e}") from e
         if not isinstance(payload, dict):
             raise DecodeError("Invalid payload string: must be a json object")
         return payload
@@ -269,7 +269,7 @@ def _validate_iat(
         try:
             iat = int(payload["iat"])
         except ValueError:
-            raise InvalidIssuedAtError("Issued At claim (iat) must be an integer.")
+            raise InvalidIssuedAtError("Issued At claim (iat) must be an integer.") from None
         if iat > (now + leeway):
             raise ImmatureSignatureError("The token is not yet valid (iat)")
 
@@ -282,7 +282,7 @@ def _validate_nbf(
         try:
             nbf = int(payload["nbf"])
         except ValueError:
-            raise DecodeError("Not Before claim (nbf) must be an integer.")
+            raise DecodeError("Not Before claim (nbf) must be an integer.") from None
 
         if nbf > (now + leeway):
             raise ImmatureSignatureError("The token is not yet valid (nbf)")
@@ -296,7 +296,7 @@ def _validate_exp(
         try:
             exp = int(payload["exp"])
         except ValueError:
-            raise DecodeError("Expiration Time claim (exp) must be an integer.")
+            raise DecodeError("Expiration Time claim (exp) must be an integer.") from None
 
         if exp <= (now - leeway):
             raise ExpiredSignatureError("Signature has expired")

jwt/jwks_client.py

@@ -60,7 +60,7 @@ def fetch_data(self) -> Any:
         except (URLError, TimeoutError) as e:
             raise PyJWKClientConnectionError(
                 f'Fail to fetch data from the url, err: "{e}"'
-            )
+            ) from e
         else:
             return jwk_set
         finally: