addu390 / crud-flask-example

CRUD Operations of inventory with deletion comments and undeletion for Spotify Fall 2022 Backend Developer Internship

Inventory Management - Shopify Fall 2022

CRUD Operations of inventory with deletion comments and undeletion.

• Repl.it Repo: https://replit.com/@addu390/shopify-inventory-management
• Repl.it Application: https://shopify-inventory-management.addu390.repl.co/

Requirements

• Basic CRUD Functionality.
• When deleting, allow deletion comments and undeletion.

Replit Set-up

• The .replit file pre-configured to RUN on Replit
• Or run the below commands in the same order in Replit shell.

pip install -r requirements.txt
export FLASK_APP=setup.py
flask db init
flask db migrate -m "Migrate Tables"
flask db upgrade
flask run --host=0.0.0.0 --port=80

Set export FLASK_DEBUG=1 for auto-reload.

Usage

• Add action button to add an item to the inventory with details such as Title, Description, and Quantity.
• After adding, Edit or Delete the item, where Edit is a simple update operation on allowed fields.
• delete in this context is a soft delete. Ensure to add a comment mentioning the reason for deletion.
• After deleting, undo the deletion if necessary while keeping track of the delete/restore history; the deletion history record will now be updated to RESTORED
• Lists are paginated; use < Newer | Older > to navigate across pages.

Note:

• The history is not limited to the inventory table or delete operation and is extendable for other operations and entities.
• The Inventory and History tables are always consistent, with "all-or-nothing" atomic transactions.
• At any given point, there can only be one DELETED record of an item and 1-or-more record of RESTORED.
• While having individual backend and frontend applications is ideal, the Jinja templating engine is used for simplicity to render the UI.

Low Coupling and High Cohesion:

• The storage layer is de-coupled; changing the datastore would require changes only in storage.py
• The resource/API layer routes.py only depends on the services classes (InventoryService and HistoryService) and not the storage layer.