Module wappdriver.error

This module error.py defines custom Wappdriver Exception. WappDriver Excpetion helps in abstracting internal exception details from the end user

''' 
This module error.py defines custom Wappdriver Exception. 
WappDriver Excpetion helps in abstracting internal exception details from the end user

'''
import functools

import logging


class WappDriverError(Exception):
    '''
    Custom Exception Class

    WappDriverError is to be raised for errors in functioning of WappDriver.

    ---
    ### Attributes

    internal - - actual exceptions and full traceback which are being abstracted away from end user

    problem  - -  what could have went wrong according to the developer 

    message -- custom message explainng what could have caused the error and how to resolve it. When displayed, message is prefixed with the words `Make sure to have:` 

    ---
    - The `problem` and current time will be the heading of any particular log
    - `internal` is not shown to the user, but logged.

    ---
    Raising an WappDriverError automatically logs the entire internal error messages with timestamps.The logs are not displayed to the user, rather they are appended to the log file.
    '''

    def __init__(self, internal, problem, message):
        self.internal = internal
        self.problem = problem
        self.message = message
        super().__init__(self.message)
        logging.debug(f'''\n{problem}\n\n{internal}''')

    def __str__(self):
        return f'''
        Please check Internet Connection and always use the latest version of wappdriver. 
        You must have matching versions of Chrome and Chromedriver.
        ------------------------------------------------------------------------------------
        WappDriver Error  : {self.problem} \n
        {self.message} \n
        For Help Visit http://bit.ly/wappdriver
        -----------------------------------------------------------------------------------\n
        '''


def handle_errors(problem, message=None, cure=None):
    '''
    -- FOR INTERNAL USE ONLY --

    Write the vulnerable code inside a function. And decorate it with `handle_error`. There should be no `return` statement inside the vulnerable function. The intended use case is for a procedural function.

    If the cure method is provided, it is run after handling errors. Nothing is done if cure raises errors. Make sure to have an error free cure.

    Example use 

    ```python
    # when displayed, message is prefixed with the words `Make sure to have:` 
    @handle_errors(problem='this not done',message='that')
    def vulnerable_function(arg):
        print('fishy errors')
        print(1/0)
    ```

    After being decorated, the vulnerable function will return `True` or `False` to the caller

    - `True` will be returned in case of no error
    - If an error is caught it will be handled and beautified message will be displayed to user
        - The internal details of the Exception and full traceback will be logged.
        - `False` will be returned to the caller.


    `handle_errors` is a Decorator Factory which is used to create a decorator that takes arguments
    '''

    def decorator_func(vulnerable_func):
        '''
        Actual Decorator to handle errors. It is nested inside a decorator factory, 
        as this decorator needs to take two arguments.

        '''
        @functools.wraps(vulnerable_func)
        def wrapper_func(*args, **kwargs):
            '''
            Wrapper Function to wrap vulnerable functions in WappDriver.
            This is internally used by WappDriver. 

            Not intended to be used by users of WappDriver
            '''
            try:
                vulnerable_func(*args, **kwargs)
                return True  # when the vulnerable code does not raise any error
            except Exception as internal:
                try:
                    raise WappDriverError(internal, problem, message)
                except Exception as err:
                    # Beautified Error message is printed and False is returned to caller
                    logging.exception(err)
                    if cure:
                        cure()
                    return False
        return wrapper_func
    return decorator_func

Functions

def handle_errors(problem, message=None, cure=None)

– FOR INTERNAL USE ONLY –

Write the vulnerable code inside a function. And decorate it with handle_error. There should be no return statement inside the vulnerable function. The intended use case is for a procedural function.

If the cure method is provided, it is run after handling errors. Nothing is done if cure raises errors. Make sure to have an error free cure.

Example use

# when displayed, message is prefixed with the words `Make sure to have:` 
@handle_errors(problem='this not done',message='that')
def vulnerable_function(arg):
    print('fishy errors')
    print(1/0)

After being decorated, the vulnerable function will return True or False to the caller

• True will be returned in case of no error
• If an error is caught it will be handled and beautified message will be displayed to user
  • The internal details of the Exception and full traceback will be logged.
  • False will be returned to the caller.

handle_errors() is a Decorator Factory which is used to create a decorator that takes arguments

Expand source code

def handle_errors(problem, message=None, cure=None):
    '''
    -- FOR INTERNAL USE ONLY --

    Write the vulnerable code inside a function. And decorate it with `handle_error`. There should be no `return` statement inside the vulnerable function. The intended use case is for a procedural function.

    If the cure method is provided, it is run after handling errors. Nothing is done if cure raises errors. Make sure to have an error free cure.

    Example use 

    ```python
    # when displayed, message is prefixed with the words `Make sure to have:` 
    @handle_errors(problem='this not done',message='that')
    def vulnerable_function(arg):
        print('fishy errors')
        print(1/0)
    ```

    After being decorated, the vulnerable function will return `True` or `False` to the caller

    - `True` will be returned in case of no error
    - If an error is caught it will be handled and beautified message will be displayed to user
        - The internal details of the Exception and full traceback will be logged.
        - `False` will be returned to the caller.


    `handle_errors` is a Decorator Factory which is used to create a decorator that takes arguments
    '''

    def decorator_func(vulnerable_func):
        '''
        Actual Decorator to handle errors. It is nested inside a decorator factory, 
        as this decorator needs to take two arguments.

        '''
        @functools.wraps(vulnerable_func)
        def wrapper_func(*args, **kwargs):
            '''
            Wrapper Function to wrap vulnerable functions in WappDriver.
            This is internally used by WappDriver. 

            Not intended to be used by users of WappDriver
            '''
            try:
                vulnerable_func(*args, **kwargs)
                return True  # when the vulnerable code does not raise any error
            except Exception as internal:
                try:
                    raise WappDriverError(internal, problem, message)
                except Exception as err:
                    # Beautified Error message is printed and False is returned to caller
                    logging.exception(err)
                    if cure:
                        cure()
                    return False
        return wrapper_func
    return decorator_func

Classes

class WappDriverError (internal, problem, message)

Custom Exception Class

WappDriverError is to be raised for errors in functioning of WappDriver.

---

Attributes

internal - - actual exceptions and full traceback which are being abstracted away from end user

problem - - what could have went wrong according to the developer

message – custom message explainng what could have caused the error and how to resolve it. When displayed, message is prefixed with the words Make sure to have:

---

• The problem and current time will be the heading of any particular log
• internal is not shown to the user, but logged.

---

Raising an WappDriverError automatically logs the entire internal error messages with timestamps.The logs are not displayed to the user, rather they are appended to the log file.

Expand source code

class WappDriverError(Exception):
    '''
    Custom Exception Class

    WappDriverError is to be raised for errors in functioning of WappDriver.

    ---
    ### Attributes

    internal - - actual exceptions and full traceback which are being abstracted away from end user

    problem  - -  what could have went wrong according to the developer 

    message -- custom message explainng what could have caused the error and how to resolve it. When displayed, message is prefixed with the words `Make sure to have:` 

    ---
    - The `problem` and current time will be the heading of any particular log
    - `internal` is not shown to the user, but logged.

    ---
    Raising an WappDriverError automatically logs the entire internal error messages with timestamps.The logs are not displayed to the user, rather they are appended to the log file.
    '''

    def __init__(self, internal, problem, message):
        self.internal = internal
        self.problem = problem
        self.message = message
        super().__init__(self.message)
        logging.debug(f'''\n{problem}\n\n{internal}''')

    def __str__(self):
        return f'''
        Please check Internet Connection and always use the latest version of wappdriver. 
        You must have matching versions of Chrome and Chromedriver.
        ------------------------------------------------------------------------------------
        WappDriver Error  : {self.problem} \n
        {self.message} \n
        For Help Visit http://bit.ly/wappdriver
        -----------------------------------------------------------------------------------\n
        '''

Ancestors

• builtins.Exception
• builtins.BaseException