Usage

The error-manager module provides your project with

a single way to define and register a default project error code
add specific error data to a default error code when needed
a enumator class to group errors for a specific domain in your project
a ErrorList class to retrieve error descriptions from error codes

Defining an error code

The error-manager package provide a simple non mutable dataclass ErrorCode that should be used to define error codes:

from errors import ErrorCode

MY_DEFAULT_ERROR_CODE = ErrorCode(
        code='ERR_MYERR_0001',
        description='my default error code'
)

Register an error code

Once the error code is defined it can be registered against the ListErrors class using register_error()

from errors import ListErrors

ListErrors.register_error(
    error_key = 'MY_DEFAULT_ERROR_CODE',
    error  = MY_DEFAULT_ERROR_CODE
)

Retrieving an error code

After registration the ErrorCode instance be retrieved from the ListErrors class using the error_key throughout your project:

from errors import ListErrors
error = ListErrors.MY_DEFAULT_ERROR_CODE

Retrieving error description

In case you have only persisted the error code without the error description you can use ListErrors class method error_description to retrieve the error description.:

>>> from errors import ListErrors
>>> ListErrors.error_description('ERR_MYERR_0001')
'my default error code'

Enumarator with error Codes

When needed you can group a set of error codes for a specific part of your project by using FunctionalErrorsBaseClass:

from errors.base import FunctionalErrorsBaseClass

class MyErrors(FunctionalErrorsBaseClass):
    """Class to define enumerator with functional errors."""
    CONNECTIVITY_ERROR = ErrorCode(
        code='GD_NETW_0001',
        description='Network connectivity issues')

    INVALID_XML_IN_RESPONSE = ErrorCode(
        code='GD_CONV_00201',
        description='Response contains invalid XML')

    INVALID_JSON_IN_RESPONSE = ErrorCode(
        code='GD_CONV_00101',
        description='Response contains invalid JSON')

Register an ErrorCodes enumerator

This class can then be registered in one go against the ListErrors class using class method register_errors():

>>> from errors import ListErrors
>>> ListErrors.register_errors(MyErrors)
>>> ListErrors.CONNECTIVITY_ERROR
ErrorCode(code='GD_NETW_0001', description='Network connectivity issues',
error_data=<class 'dict'>)

Adding data to the error

When specific data needs to be added to the error you can use add_error_data() to add data to the non mutable ErrorCode instance:

>>> from errors import ListErrors, add_error_data
>>> the_error = ListErrors.UNEXPECTED_404_RESPONSE
>>> add_error_data(
        error=the_error,
        error_data={'url_called': 'www.url.com'})
>>> the_error
ErrorCode(code='GD_RESP_0004', description='URL returned unexpected 404
response', error_data={'url_called': 'www.url.com'})

Check if an object is of (sub)class ErrorCode

When you want to check if a return value is either an error_code you can use is_error(). This method checks if an object is of class ErrorCode or a subclass there of:

>>> from errors import ListErrors, is_error
>>> the_error = ListErrors.UNEXPECTED_404_RESPONSE
>>> is_error(the_error)
True
>>> is_error({'data': 'or_any_other_object')}
False