Error Handling

class UnknownArgumentError(Exception):
    """
    Raised when an unknown or invalid CLI argument is encountered.
    Typically occurs during argument parsing.
    """

class ParamError(Exception):
    """
    Base exception for parameter processing and validation errors.
    Parent class for all parameter-related exceptions.
    """

class ParamSyntaxError(ParamError):
    """
    Raised when parameter syntax is malformed or invalid.
    Common with JSON parameter values or shorthand syntax.
    """

class ParamUnknownKeyError(ParamError):
    """
    Raised when an unknown parameter key is encountered.
    Occurs when using invalid keys in JSON or shorthand parameters.
    """

class ErrorHandler:
    """
    HTTP error handler for AWS service responses.
    Processes 4xx and 5xx HTTP errors into user-friendly messages.
    """
    
    def __init__(self):
        """Initialize error handler."""
    
    def __call__(self, parsed, **kwargs):
        """
        Process HTTP error response.
        
        Parameters:
            parsed: botocore parsed response
            **kwargs: additional context information
        """

class ClientError(Exception):
    """
    Raised for HTTP 4xx client errors.
    Indicates issues with the request (authentication, validation, etc.).
    """
    
    def __init__(self, error_response, operation_name):
        """
        Initialize client error.
        
        Parameters:
            error_response: dict, AWS error response
            operation_name: str, AWS operation name
        """

class ServerError(Exception):
    """
    Raised for HTTP 5xx server errors.
    Indicates issues with AWS service availability or processing.
    """

class BaseOperationError(Exception):
    """
    Base class for operation-level errors.
    Parent class for service operation exceptions.
    """

def write_exception(ex, outfile):
    """
    Write exception information to output file.
    
    Parameters:
        ex: Exception instance
        outfile: file-like object for error output
    """

from awscli.utils import write_exception
import sys

try:
    # AWS CLI operation that might fail
    result = driver.main(['s3', 'ls', 's3://nonexistent-bucket'])
except Exception as e:
    # Write error to stderr with proper formatting
    write_exception(e, sys.stderr)
    sys.exit(1)

from awscli.arguments import UnknownArgumentError
from awscli.argprocess import ParamError, ParamSyntaxError

def process_arguments(args):
    try:
        # Process CLI arguments
        processed_args = parse_arguments(args)
        return processed_args
    except UnknownArgumentError as e:
        print(f"Unknown argument: {e}")
        return None
    except ParamSyntaxError as e:
        print(f"Parameter syntax error: {e}")
        return None
    except ParamError as e:
        print(f"Parameter error: {e}")
        return None

from botocore.exceptions import ClientError, NoCredentialsError
from awscli.clidriver import main

def execute_aws_command(command_args):
    try:
        exit_code = main(command_args)
        return exit_code == 0
    except ClientError as e:
        error_code = e.response['Error']['Code']
        error_message = e.response['Error']['Message']
        
        if error_code == 'NoSuchBucket':
            print(f"Bucket does not exist: {error_message}")
        elif error_code == 'AccessDenied':
            print(f"Access denied: {error_message}")
        else:
            print(f"AWS error ({error_code}): {error_message}")
        return False
    except NoCredentialsError:
        print("AWS credentials not configured")
        return False
    except Exception as e:
        print(f"Unexpected error: {e}")
        return False

from awscli.customizations.commands import BasicCommand
from awscli.arguments import ParamError

class MyCustomCommand(BasicCommand):
    NAME = 'my-command'
    
    def _run_main(self, parsed_args, parsed_globals):
        try:
            # Custom command logic
            self.process_input(parsed_args.input_file)
            return 0
        except FileNotFoundError:
            print(f"Input file not found: {parsed_args.input_file}")
            return 1
        except ParamError as e:
            print(f"Parameter error: {e}")
            return 1
        except Exception as e:
            print(f"Command failed: {e}")
            return 1
    
    def process_input(self, input_file):
        """Process input file with error handling."""
        if not os.path.exists(input_file):
            raise FileNotFoundError(f"File not found: {input_file}")
        # Process file...

def enhanced_error_handler(parsed, **kwargs):
    """Enhanced error handler with context preservation."""
    if 'Error' in parsed:
        error_info = parsed['Error']
        
        # Preserve original error context
        context = {
            'operation': kwargs.get('operation_name'),
            'service': kwargs.get('service'),
            'request_id': parsed.get('ResponseMetadata', {}).get('RequestId'),
            'http_status': parsed.get('ResponseMetadata', {}).get('HTTPStatusCode')
        }
        
        # Create enhanced error message
        enhanced_message = format_error_with_context(error_info, context)
        print(enhanced_message)

import logging

# Enable debug logging for detailed error information
logging.basicConfig(level=logging.DEBUG)

# AWS CLI will provide additional error context:
# - HTTP request/response details
# - Parameter validation information  
# - Service model validation
# - Plugin execution traces

import time
from botocore.exceptions import ClientError

def execute_with_retry(command_args, max_attempts=3):
    for attempt in range(max_attempts):
        try:
            return main(command_args)
        except ClientError as e:
            if e.response['Error']['Code'] == 'Throttling':
                if attempt < max_attempts - 1:
                    wait_time = 2 ** attempt  # Exponential backoff
                    time.sleep(wait_time)
                    continue
            raise

def execute_with_fallback(primary_command, fallback_command):
    try:
        return main(primary_command)
    except ClientError as e:
        if e.response['Error']['Code'] in ['ServiceUnavailable', 'InternalError']:
            print("Primary service unavailable, trying fallback...")
            return main(fallback_command)
        raise