SIE508 Homework 5-Exceptions Solved

Exceptions

1. Add appropriate exceptions and exception handling to persistent basic_backend.py and Model.py.

In this homework assignment, we revisit the basic_backend.py and the Model.py (code is attached). In this version, the basic_backend.py provides a CRUD interface that stores items to a file. The ModelBasic inherits from Model and currently has no exception handling, that is, it does not catch any exception that the basic_backend.py might raise.

Assignment: Introduce your own, new exceptions for the Model class. It is not really necessary since Model could raise the same exceptions as basic_backend.py. However, this is an assignment to get some experience with exception writing, using and handling. Make sure, Model raises its own exceptions that convey useful error messages.

1. A)  Basic_backend.py needs to be equipped to handle FileIO errors and do the appropriate exception handling for this code. Are there other places to add exception handling?
2. B)  ModelBasic needs to handle any exceptions that basic_backend.py might raise and raise exceptions itself around critical code blocks.
3. C)  Check for additional critical blocks you could find opportunities for exception handling.

Deliverables for this HW assignment:

1. all necessary .py files in a .zip file