Error Handling

class Error(Exception):
    """
    Generic JOSE Error.
    
    Base class for all JOSE-related exceptions. Inherit from this
    class when creating custom JOSE error types.
    """

class SerializationError(Error):
    """
    JSON serialization error.
    
    Raised when an object cannot be serialized to JSON format,
    typically due to unsupported data types or circular references.
    """

class DeserializationError(Error):
    """
    JSON deserialization error.
    
    Raised when JSON data cannot be parsed or converted to the
    expected object type. Common causes include:
    - Invalid JSON structure
    - Missing required fields
    - Type conversion failures
    - Size validation failures
    """
    
    def __str__(self) -> str:
        """Returns formatted error message with 'Deserialization error:' prefix"""

class UnrecognizedTypeError(DeserializationError):
    """
    Unrecognized type error.
    
    Raised when attempting to deserialize a JSON object with an
    unknown or unsupported type identifier.
    """
    
    def __init__(self, typ: str, jobj: Any) -> None:
        """
        Initialize with type information.
        
        Parameters:
        - typ: The unrecognized type identifier
        - jobj: Full JSON object that caused the error
        """
    
    def __str__(self) -> str:
        """Returns detailed error message with type and full object"""
    
    typ: str  # The unrecognized type identifier
    jobj: Any  # Full JSON object

from josepy import JWS, JWKRSA, RS256
from josepy.errors import Error, DeserializationError, SerializationError

try:
    # Attempt to load invalid JWS
    jws = JWS.json_loads('{"invalid": "jws_structure"}')
except DeserializationError as e:
    print(f"Failed to parse JWS: {e}")
    # Handle invalid input gracefully

try:
    # Attempt signature verification with wrong key
    payload = jws.verify(wrong_key)
except Error as e:
    print(f"Signature verification failed: {e}")
    # Handle authentication failure

from josepy import JWK
from josepy.errors import UnrecognizedTypeError, DeserializationError

# Example JSON with unknown key type
unknown_jwk_json = '''
{
    "kty": "unknown_key_type",
    "use": "sig",
    "n": "...",
    "e": "AQAB"
}
'''

try:
    jwk = JWK.json_loads(unknown_jwk_json)
except UnrecognizedTypeError as e:
    print(f"Unknown key type: {e.typ}")
    print(f"Full object: {e.jobj}")
    # Could fall back to a different key handling strategy
    
except DeserializationError as e:
    print(f"General deserialization error: {e}")
    # Handle other parsing issues

import json
from josepy import JWKRSA
from josepy.errors import DeserializationError

# Detailed error handling with context
def safe_jwk_load(jwk_data: str) -> Optional[JWKRSA]:
    try:
        # First validate JSON structure
        json_obj = json.loads(jwk_data)
        
        # Then attempt JWK deserialization
        return JWKRSA.json_loads(jwk_data)
        
    except json.JSONDecodeError as e:
        print(f"Invalid JSON at line {e.lineno}, column {e.colno}: {e.msg}")
        return None
        
    except DeserializationError as e:
        print(f"JWK deserialization failed: {e}")
        print(f"Input data: {jwk_data[:100]}..." if len(jwk_data) > 100 else jwk_data)
        return None
        
    except Exception as e:
        print(f"Unexpected error: {type(e).__name__}: {e}")
        return None

# Usage
jwk = safe_jwk_load(potentially_invalid_jwk_json)
if jwk is None:
    print("Failed to load JWK, using default key")
    jwk = get_default_key()

import cryptography.exceptions
from josepy import RS256, JWKRSA
from josepy.errors import Error

def safe_sign_and_verify(message: bytes, jwk: JWKRSA) -> bool:
    try:
        # Sign message
        signature = RS256.sign(jwk.key, message)
        
        # Verify signature
        is_valid = RS256.verify(jwk.public_key().key, message, signature)
        return is_valid
        
    except cryptography.exceptions.InvalidSignature:
        print("Cryptographic signature operation failed")
        return False
        
    except Error as e:
        print(f"JOSE operation failed: {e}")
        return False
        
    except Exception as e:
        print(f"Unexpected error: {e}")
        return False

# Usage
success = safe_sign_and_verify(b"test message", my_jwk)
print(f"Signature test: {'PASSED' if success else 'FAILED'}")

from josepy import JWK, JWKRSA, JWKEC, JWKOct
from josepy.errors import UnrecognizedTypeError, DeserializationError

def robust_jwk_loader(jwk_json: str) -> Optional[JWK]:
    """
    Attempt to load JWK with multiple fallback strategies.
    """
    try:
        # First try generic JWK loading
        return JWK.from_json(json.loads(jwk_json))
        
    except UnrecognizedTypeError as e:
        print(f"Unknown key type '{e.typ}', trying specific loaders...")
        
        # Try specific key types as fallbacks
        json_obj = e.jobj
        
        if json_obj.get('kty') == 'RSA':
            try:
                return JWKRSA.from_json(json_obj)
            except DeserializationError:
                pass
                
        elif json_obj.get('kty') == 'EC':
            try:
                return JWKEC.from_json(json_obj)
            except DeserializationError:
                pass
                
        elif json_obj.get('kty') == 'oct':
            try:
                return JWKOct.from_json(json_obj)
            except DeserializationError:
                pass
        
        print("All fallback strategies failed")
        return None
        
    except DeserializationError as e:
        print(f"Deserialization failed: {e}")
        return None

# Usage with graceful degradation
jwk = robust_jwk_loader(received_jwk_json)
if jwk is None:
    print("Using fallback authentication method")
    # Implement alternative authentication

import logging
from josepy.errors import Error, DeserializationError, SerializationError

# Configure logging for JOSE operations
logger = logging.getLogger('josepy_operations')

def logged_jws_operation(operation_name: str, operation_func, *args, **kwargs):
    """Wrapper for JWS operations with comprehensive logging."""
    try:
        logger.info(f"Starting {operation_name}")
        result = operation_func(*args, **kwargs)
        logger.info(f"Successfully completed {operation_name}")
        return result
        
    except DeserializationError as e:
        logger.error(f"{operation_name} deserialization failed: {e}")
        raise
        
    except SerializationError as e:
        logger.error(f"{operation_name} serialization failed: {e}")
        raise
        
    except Error as e:
        logger.error(f"{operation_name} JOSE error: {e}")
        raise
        
    except Exception as e:
        logger.critical(f"{operation_name} unexpected error: {type(e).__name__}: {e}")
        raise

# Usage
try:
    jws = logged_jws_operation("JWS creation", JWS.sign, payload, key=jwk, alg=RS256)
    verified = logged_jws_operation("JWS verification", jws.verify, public_jwk)
except Error:
    # Handle JOSE-specific errors
    handle_jose_error()